CA Thyroid Reduced

3 CASE CARCINOMA OF THYROID

INTRODUCTION

Name of Hospital : National Hospital Of Sri Lanka

Name of Consultant : Dr Sarath Kumara Kollure (MS, FRCS)

Ward : 21

BHT Number : 945698

Name : Mr. T. Somarathne

Age : 55 years

Sex : Male

Address : 63/1, Kanaththa Road, Mirihana, Nugegoda.

Date of Admission : 25/5/2006

Date of Discharge : 31/5/2006

Signature of Consultant :

SUMMARY

55 year old male presented with a rapidly enlarging lump over the anterior aspect of the

neck for 7 months and hoarseness of voice during last 2 months. On examination he had a

3cm, firm nodule in left lobe of thyroid. Trachoea was deviate to right side. He was

clinically euthyriod. Thyroid function test was normal. Ultrasound scan confirmed a 2.6

cm thyroid nodule in the left lobe. Fine needle aspiration was compatible with follicular

neoplasm.

Plan was to do left lobectomy and isthmusectomy, but peroperative findings were more

favour of a thyroid carcinoma, so a total thyroidectomy was done. Histology report

showed a medullary carcinoma instead of a follicular carcinoma. Retrospective analysis

showed no family history of thyroid carcinoma or multiple endocrine syndromes. It was

more likely to be a sporadic medullar carcinoma.

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HISTORY

Presenting complaint

He presented with a lump in the anterior aspect of neck for 7 months and hoarseness of

voice for 2 months.

History of presenting complaint

He noticed a small lump in the left side of the anterior aspect of neck 7 months back. It

was gradually enlarging for a period of 5 months and then rapidly enlarged during last 2

months which made him sought treatment. Rapid enlargement was associated with

hoarseness of voice, but there was no pain or difficulty in breathing. He did not have

symptoms of hyper or hypothyroidism.

His appetite was good and he did not notice any recent weight loss. He did not have

chronic cough, haemoptysis, back pain, head ache or focal neurological symptoms.

Neither he had recent onset lumps in chest, skin or scalp. His bowel and urinary function

were normal.He had good exercise tolerance.

Past Surgical history

He has not undergone any surgery previously. There was no history of neck irradiation.

Past Medical history

Except for childhood bronchial asthma he had no other premorbid medical illness.

He had no previous thyroid enlargement or taken any antithyroid drugs. He had no history

of bleeding disorder.

Drug and food allergy

He was not allergic to any drugs, food or to adhesive tapes

Dietary history

He usually takes iodide salts

Family history

There was no family history of goiter, thyroid carcinoma or any other malignancy.

His father had diabetes mellitus.

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Social

He was a freelance translator. He had five children who were still schooling at the time.

He wife was unemployed. He got a reasonable income. He consumed alcohol and smoked

occasionally.

EXAMINATION

General Examination

He was average built and showed a normal habitus. Weight was around 67 Kg. Body

mass index was 24.3 kg/m2. His hair distribution was normal. His conjunctiva was not

pale or icteric.

His mouth and tongue was normal. There was no cervical or supraclavicular

lymphadenopathy. He did not have any tremours or palmer sweating. The ankle jerk

relaxation time was normal. There were no signs of ophthalmopathy. There was no ankle

oedema.

Thyroid examination

He had a short neck which made the palpation of the lump difficult. His voice was

slightly hoarse. There was lump over left anterior aspect of neck which moves up with

swallowing. The lump was ill defines, non tender, size 3× 3cm, hard in consistency with

irregular surface. There was a mild enlargement of the right lobe and the isthmus of the

thyroid. There was no retrosternal extension. The lump was somewhat adhered to the

underlying structures, but not attached to sternocleidomastoid muscle. Overlying skin was

normal and mobile over the lump. There was no vascular bruit over the gland or carotid

bruit. Trachoea was difficult to palpate, however it was slightly deviate to right. The neck

veins were not engorged even when raising the upper limbs. Central, deep cervical or

supraclavicular lymph nodes were not palpable.

Cardiovascular system

Blood pressure was 140/ 90 mm Mercury. Pulse was 84 per minuate. The first and the

second Heart sound were normal.

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Respiratory system

Trachoea was slightly deviated to right. Respiratory rate was 18 per minuate. There was

good and equal air entry to both lungs. No added sounds were detected.

Abdominal examination

There were no palpable masses or ascitis . Liver and spleen was not palpable. Kidneys

were not ballotable.

SUMMARY

55 year old male presented with a lump in the anterior aspect of the neck for 7 months. It

was rapidly enlarging during last 2 months associated with hoarseness of voice. He was

clinically euthyroid. There was no family history of thyroid carcinoma or goiter. On

examination he had a left side, 3cm, hard, thyroid nodule with mild enlargement of the

rest of the gland. Gland was somewhat adhered to deeper structures. Trachea was deviate

to right side and there was no retrosternal extension. Cervical lymph nodes were not

enlarged.

DIAGNOSIS

The diagnosis was suspicious solitary or dominant nodule in left lobe of

thyroid.

INVESTIGATIONS

TSH – 1.31 mic IU/ml (Normal)

Ultrasound scan neck - There was a nodule in the left lobe of the thyroid with

calcification. Diameter was around 2.6 cm. Mixed echogenic pattern observed. Right lobe

was slightly enlarged. There was no retrosternal extension. Trachoea was deviated to right

with bilateral compression at the level of isthmus. There was no enlarged cervical lymph

node. Impression was a thyroid neoplasm.

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Fine needle aspiration biopsy – It was compatible with follicular neoplasm.

Serum electrolytes – Na+ - 135.6 meq/l

K+ - 4.5 meq/l

Full blood count

Haemoglobin – 14.9 g/dl

White blood count – 10700 / L, Neutrophils – 70%

Haematocrite – 44 %

Platelet – 288,000 /L

Renal function test

Blood Urea – 20 mg/dl

Serum Creatinine – 85

Electro Cardio Gram – Normal

Chest radiography – Normal

Xray – neck – Trachoea was compressed laterally with some deviation to right. There

was no retrosternal extension. Calcification of the left lobe of thyroid gland was seen.

There was no evidence of degenerative changes in the cervical spine.

Indirect laryngoscopy – Normal moving vocal cords.

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DIAGNOSIS AFTER INVESTIGATIONS

The diagnosis was follicular neoplasm of left thyroid lobe.

Through history and examination solitary lump is most likely to be thyroid cancer.

However the diagnosis of thyroid cancer necessitates cytological or histological

confirmation.

Thyroid function test are done to assess the thyroid status of the patient. It reveals

subclinical hyper or hypothyroidism. But it rarely adds to the diagnosis of carcinoma. In

this patient the TSH was within normal range. TSH is the best indicator of thyroid

function. Free T4 and T3 is will complete the picture of full thyroid function but in this

patient it was not done as TSH was normal.

Echography (Ultrasonography) of the neck must be performed first in any patient with

possible thyroid malignancy. Echography is noninvasive and inexpensive, and it

represents the most sensitive procedure for identifying thyroid lesions and for

determining the diameters of a nodule. Echography images can help determine if a lesion

is solid or cystic and can help detect the presence of calcifications. It may be used for

image guided fine-needle aspiration biopsy (FNAB).It may detect clinically unpalpable

lymph nodes. In this patient it showed a calcified mixed echogenic 2.6 cm lesion in left

lobe of thyroid which infers a neoplatic lesion.

FNAB is considered the best first-line diagnostic procedure for a thyroid nodule; the

FNAB is a safe and minimally invasive procedure. A pathologist may experience

difficulty distinguishing benign follicular adenomas from their malignant counterparts,

because cytology does not shows vascular and capsular invasions, as in this patient.

Chest radiography electrocardiography and blood test were done to assess the patient’s

fitness for surgery. Chest radiography may help to diagnose retrosternal extension and

metastatic disease at presentation. In this patient it is very important to perform the

cervical radiography as he had clinical evidence of tracheal compression. It showed slight

deviation of the trachoea to the right with lateral compression. This allows the

anaesthetist to anticipate difficult intubation as well as risk of post operative trachoeal

collapse (trachoeomalasia)

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Indirect laryngoscopy was done to evaluate airway and vocal cord mobility and to have

preoperative documentation of any unrelated abnormalities. It is important for legal

purpose as well.

Blood grouping and cross matching was done, as there was risk of perioperative bleeding.

PLAN FOR FURTHER MANAGEMENT

Surgery is the definitive management of differentiated thyroid cancer, and various types

of operations may be performed.

As it was a follicular neoplasm (either benign or malignant), minimum of left lobectomy

and isthmusectomy needed to be done. But depending on the peroperative findings this

could extend to a total thyroidectomy.

PRE-OPERATIVE TREATMENT

Patient was fully informed of the potential complication of the surgery, especially injury

to parathyroids and recurrent laryngeal(RL) and written consent was taken. Preoperative

indirect laryngoscopy showed normal movement of the cords. A bed was reserved in

intensive care unit in case of emergency. Two unit of blood were reserved.

Patient was kept fasting from 10 pm of day prior to surgery. He was nebulized with

salbutamol in the night and early morning. He was given anxiolytic (Diazepam 10 mg) in

the night and antiemetic ( Metachlopramide 10 mg) in the morning. Patient was sent to

theatre with all investigations.

OPERATIVE DETAILS

Anaesthesia

The surgery was done under general anaesthesia with endotracheal intubation. The blood

pressure was maintained around 100/ 60 mm Mercury.

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Positioning

Patient was laid supine on the table with a sand bag under the shoulder blade and a ring

under the head, so that the neck is extended, but not over extended. Head was raise about

(15 – 20°) and the table was braked so that patient was in semi seated position, in order to

prevent neck engorgement. Monopolar diathermy plate was placed over the patient’s right

buttock. Abdomen was secured with a strap. The site of incision was marked 2 finger

breaths above the suprasternal notch parallel to the skin crease line, using indelible

marker pen.

Skin preparation

Skin was prepared with 70 % alcohol starting from chin to the sterna angle including both

shoulders. Head was draped in double towel of which the triangular towel wrapped

around the head. A four towel squire applied and secured with clip exposing an area from

chin to the suprasternal notch.

Procedure

The surgeon was standing on right side. Skin was incised with No 22 blade and extended

as far as medial borders of the sternocleidomastoid muscles. Subcutaneous tissues and

platysma were cut along the line of incision till the deep cervical fascia was reached.

Haemostasis achieved using monopolar diathermy.

Then Superior and inferior skin flaps were raised. Two Allis forceps were placed on the

platysma superiorly and assistant was asked to pull vertically to demonstrate the blood

less plane between platysma and strap muscles. The space was created between these two

structures as far as thyroid cartilage (palpable notch) using sharp and blunt dissection.

However meticulously the dissection was done, the anterior jugular veins got punctured

and had to be ligated using 2/0 polygalactin 910. The Allis forceps were replaced on the

inferior flap and the flap was raised up to suprasternal notch. Allis forceps were placed on

midpoint of each flap, held by assistant. As Joll’s retractor was not available at that time a

modified method was used. Each flap was sutured to draped towel using No 1 black silk

going through platysma at 3 points thus exposing the underlying strap muscles.

Midline raphe between strap muscles was identified. Fascia over either side of the midline

was picked by two artery forceps and incised in between using diathermy and extended

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superiorly and inferiorly. Some small branches of anterior jugular vein traversing the

bloodless field had to be diathermised. The incision was deepened down until upto the

surface of the gland without damaging to the vessels running over it. The correct plane of

dissection was identified by sudden filing up of blood vessels coursing over the gland.

Findings

There was a 3cm size, irregular surfaced, hard nodule in the lower pole of the left lobe

extending to isthmus. There were some calcified areas over the nodule. Right lobe was

slightly enlarged. The glad was adhered to the strap muscle and difficult to separate.

There were no enlarged lymph nodes. Trachoea was slightly deviated to right and

compressed by the gland from either side. There was no retrosternal extension.

The plan was to do total thyroidectomy as the nodule looked malignant

The left lobe was approached first standing on right side of the patient. The medial

boarder of the strap muscle was held up using Langanbeck retractors. A space was

developed between the strap muscle and the thyroid by sweeping away the muscle using

pleget. It was difficult to separate gland from the strap muscle as there was adhesions.

Small vessels crossing this space was were diathermized . Middle thyroid vein was

identified and ligated with 3/0 polygalactin 910 and divided. It was difficult to mobilize

the lobe medially as there was adhesion and left strap muscle had to be transected.

Traction was applied to the left lobe using a guaze swab between surgeon’s index and

middle fingers and put the tissues lateral to the gland under tension. With blunt dissection

the space between the gland the oesophagus and posterolateral tissues was opened up.

Dissection was done parallel to the recurrent laryngeal nerve to minimize the risk of

damage. Inferior thyroid artery and its branches were identified. The nerve was found

(using toothpaste sign) running deep to the artery. The attempt to follow the nerve upward

was unsuccessful due to adhesions.

The superior pole of the left lobe was dealt next. The gland was gently pulled down

wards. The adherent muscle fibers of the strap muscles were swept off from the gland

using plegets to identify the superior pole vessels. The artery forceps was passed under

the vessels well away from the external laryngeal nerves close to the gland. The vessel

was doubly ligated using No 2/0 polygalatin 910 sutures and divided. Upper pole was

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eased down sweeping away the adherent muscle. A posterior branch of the superior

thyroid vessel was found and treated with similar manner.

Next the inferior thyroid vessel was approached. Having identified the RL Nerve, keeping

it sight, individual branches of the thyroid vein and artery was identified and clipped

closed to the gland. Care was taken to avoid damage to the parathyroids which lied at the

junction of the vessel and the nerve. Lateral thyroid ligament was identified. Using a

haemostatic clip a tunnel was created parallel to the nerve and the fascia was clipped and

ligated without damaging the nerve.

An attempt was made to create a space between the gland and the trachoea using artery

forceps. But it failed due to adhesions. Using diathermy the left lobe and the isthmus was

dissected free from the trachoea and continued to the right anteromedial aspect of the

trachoea. The bleeding raw surface was over sown with 2/0 polygalactine 910. A small

pyramidal lobe was found arising from the isthmus. It was followed up to the thyroid

cartilage and dissected free from the trachoea and larynx. The isthmus vessels were found

on the way and ligated and divided. A lymph node was found close to the lobe and was

dissected with the pyramidal lobe.

Right lobe was approached by standing on left side of the patient. Identifying the

recurrent laryngeal nerve, securing the superior and inferior poles was done as described

above. Total thyroidectomy was done and the specimen was sent for histology. Any

bleeding points were identified and clipped or ligated. Each side of the thyroid bed was

packed with gauze swabs

Closing

The sand bag was removed and the head was brought back to neutral position. Blood

pressure was brought up to preoperative values. The two swabs occupying the thyroid bed

was gently removed to see whether there was any bleeding. The space was filled with

distilled water and observed for small bleeding points. The parathyroids were visualized

to see whether they were devascularized (change of colour).

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The silk sutures which were used to secure the skin flaps to the drapes were removed.

Further bleeding points in the skin flaps were diathermized . Strap muscles were re-

approximated using polygalactine 910 3/0 interrupted sutures. Platysma and the skin were

approximated with metal clips.

While extubating the patient the anaesthetist was asked to look at the cords and both

cords were found normal.

POST OPERATIVE MANAGEMENT

Patient was managed in the ward post operatively. He was propped up in a low fowler’s

position with head and shoulder elevated (10-20°) after recovery from anaesthesia. Pain

relief was achieved with diclofenac sodium suppositories and intra muscular injection of

pethidine 75 mg. Patient’s blood pressure, pulse and respiratory rates were monitored

every 15 minute for first 2 hours and ever 3 minute for next 2 hours and hourly thereafter.

He was specially observed for stridor and difficulty in breathing. The clip removal was

kept ready in case of emergency. He had mild sore throat during first 24 hours. Oral fluid

was started around 6 hours after surgery and Intravenous fluid was discontinued. Steam

inhalation and nebulization were commenced from first day of surgery.

On the first post operative day the patient was mobilized. He had no clinical features of

hypocalcaemia but mild degree of hoarseness. The patient was given a normal diet.

Thyroxin (200 mic grams daily) was started as suppressive dose.

On the second day of surgery the clips were removed and the patient was discharged with

the plan of reviewing him at the clinic in two weeks.

FOLLOW-UP

The patient was seen at clinic after 2 weeks with histology report and serum calcium

level. On examination the incision site was healed well and there was no collection of

seroma. He was clinically euthyroid. There were no symptoms of hypocalcaemia.

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The histology report gave a different histological diagnosis.

It showed a medullary carcinoma size 2.6 cm with classification. There was vascular

and capsular invasion. Resection margins were free of tumour. Three lymph nodes

were identified and did not show any tumour deposits.

PLAN FOR FUTURE MANAGEMENT

In order to local control of the disease it is necessary to do secondary surgery to clear the

central node of the neck. This will give the lymph node status which is very important for

the prognosis of the patient.

The plan was to do tumour marker calcitonin level. Response to primary surgery can be

assessed clinically, and by the measurement of clacitonin levels. The presence of an

elevated but stable calcitonin level post-operatively may be managed conservatively.

Progressively rising levels should trigger imaging for further staging. In the absence of

recurrent symptoms, appropriate intervals are 6–12 months.

There is no need to give suppressive dose of thyroxin. So the plan was to reduce the

thyroxin level to therapeutic dose and maintain it with regular thyroid function test.

Further investigations are necessary to exclude pheochromocytoma in this patient. It is

important to take detail history and examination exclude family history of medullary

carcinoma and to identify multiple endocrine neoplasia (MEN) syndrome.

There are meager facilities for genetic studies in Sri Lanka. Ideally the patient and the

family members should be screened for RET protooncogene.

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DISCUSSION

The patient, Mr. Basil James was diagnosed of having a suspicious solitary thyroid of

follicular cell origin and underwent total thyroidectomy, in contrary the histology

revealed a medullar carcinoma. It is a very rare variety of thyroid carcinoma and needs to

be managed differently from differentiated thyroid carcinoma. Tackling the dilemma of

two different diagnoses at preoperatively and postoperatively was found very interesting

to be discussed here.

Introduction

Although thyroid nodules are extremely common, malignant lesions derived from thyroid

epithelial cells are relatively rare. Clinically recognized thyroid carcinomas constitute less

than 1% of all human malignant tumors. It is the most common endocrine malignant

lesion (90% of all endocrine cancers) and is responsible for more deaths than all other

endocrine cancers combined. 1 Nevertheless, with appropriate treatment, the survival rate

from thyroid cancer is very high.

Thyroid nodule

This patient presented with a solitary thyroid nodule which is common presentation of

thyroid disease. This is of concern because of the risk of malignancy and hyperfunction.

Epidemiology

The reported prevalence of thyroid nodules varies with the method of screening. In

autopsy series, up to 50% of clinically normal thyroid glands contain nodules. A lower

prevalence is found by ultrasonography. For example, nodules were found in 27% of

randomly selected people aged 19–50 years in an iodine-sufficient area of Finland; only

5% of these people had a clinically detectable abnormality. Fifty per cent of people with

clinically detected solitary nodules have additional nodules when studied further by

ultrasonography 2.

Nodules are more common in women and in areas of iodine deficiency. Exposure to

ionising radiation in childhood and adolescence increases the risk of both nodules and

thyroid carcinoma 2.

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Reports of the risk of malignancy in thyroid nodules vary. An Italian study of more than

5000 consecutive patients with “cold” thyroid nodules reported an incidence of

malignancy of 5.3% in those from iodine-sufficient areas. Risk factors for malignancy

included male sex and age less than 30 years or greater than 60 years 2.

This patient had no history of irradiation or family history of thyroid carcinoma. He was

taking iodide salts regularly. The only risk factor identified was the male gender.

Diagnosis

Thyroid nodules are usually found by the patient or a family member, or during a general

physical examination, but increasingly they are incidentally discovered during neck

imaging undertaken for other reasons, such as carotid duplex ultrasonography. It is

important to determine whether the nodule is hyperfunctioning or malignant.

History is rarely helpful in differentiating benign and malignant nodules. An exception is

a history of head and neck irradiation in childhood or teenage years. This is by far the

greatest risk factor for thyroid malignancy, with a risk of carcinoma in nodules in this

group of 35%–40%, in contrast to 5% in the general population.1. Another exception is a

family history of medullary carcinoma of the thyroid, which should prompt consideration

of familial medullary thyroid cancer or MEN type 2, the latter being associated with

hyperparathyroidism and phaeochromocytoma.

Physical examination is also rarely helpful in differentiating benign and malignant

nodules, unless there is evidence of invasion of other structures in the neck or enlarged

regional lymph nodes, which suggest malignancy.

Suspicion of malignancy if

Recent origin

Firm, fixed and irregular

Increasing in size rapidly

Family History of thyroid CA

History of neck irradiation

Young patient (<15yrs) and elderly patient (>65yrs) specially man

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Hoarseness of voice

Cervical lymphadenopathy

This patient, Mr. Basil James’s thyroid lump also had a recent rapid enlargement

associated with hoarseness of voice. On examination the lump was hard and irregular.

These features were in favors of a malignancy. So, further investigations were done to

confirm the diagnosis. It included Biochemical, cytological and radiological assessment.

Investigation of thyroid nodule

Biochemical assessment

Measurement of thyroid-stimulating hormone (TSH) level is helpful, as suppression

suggests that a nodule is hyperfunctioning. Some of these patients will also have a raised

level of serum free thyroxine (T4). Hyperfunctioning solitary nodules carry a low risk of

malignancy (at least in adults).2When TSH level is normal, assay of serum free T4 adds

no further information. A raised TSH level in an elderly patient with a large, rapidly

growing thyroid mass suggests thyroid lymphoma.2

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Serum calcitonin level should be measured if there is a family history of medullary

carcinoma of the thyroid, as a raised level is both sensitive and specific for this cancer.

However, this measurement is not cost-effective in the initial evaluation of nodules.2

Thyroid imaging

Thyroid imaging should not be routine, but should be used to answer a specific clinical

question.

Thyroid scanning using pertechnetate (99MTc) (and formerly radioiodine, 131I) was

traditionally used to screen thyroid nodules for malignancy. The finding of a

hyperfunctioning or “hot” nodule (uptake of tracer within the nodule with suppression of

uptake in the surrounding normal thyroid tissue) excludes malignancy in almost all

patients. Current recommendations are that patients with TSH suppression should proceed

to pertechnetate scanning to confirm that the nodule is hot. The patient can then be treated

with therapeutic radioiodine or lobectomy. A non-functioning or “cold” nodule was

thought to indicate increased risk of malignancy. Unfortunately, most nodules are cold,

but perhaps only 5%–15% of these are malignant. 2 Pertechnetate scans are thus not

advocated for assessing a nodule in patients who are euthyroid or hypothyroid.

Thyroid ultrasonography is commonly performed. Although some ultrasonographic

features, such as punctate calcification and irregular or blurred margins, suggest papillary

carcinoma, routine ultrasonographic studies rarely aid clinical decision-making.2 Despite

early suggestions that nodules in multinodular goitres are less likely to be malignant,

more recent studies show that the risk of malignancy in a dominant nodule in this

condition is similar to that in a solitary nodule.2

Computed tomography is rarely necessary, but can be useful in delineating the extent of

disease in patients with known thyroid cancer. It should be remembered that use of

iodinated contrast medium reduces technetium uptake and may reduce the diagnostic

utility of pertechnetate scanning.

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Fine-needle aspiration biopsy

In the absence of TSH suppression, biopsy by fine-needle aspiration should be the first-

line investigation for a solitary nodule or a dominant nodule in a multinodular goitre. An

exception may be an “incidentaloma” (incidentally discovered small thyroid nodule.

The success of a biopsy depends on the adequacy of the specimen and skill of the

cytopathologist. In experienced hands, the false negative rate is less than 5%, and the

false positive rate less than 1%. 2 Ultrasound guidance is preferred by some practitioners

and is needed for impalpable lesions that warrant fine-needle aspiration biopsy.

The cytopathological report should be one of the following: insufficient for diagnosis;

malignant; atypical; a follicular neoplasm; or benign. The presence of colloid and bland

follicular cells suggests a benign lesion. The report should indicate adequacy of the

specimen, as malignancy cannot be excluded if material is insufficient.

Papillary and often medullary carcinoma can be recognised on fine-needle aspiration

biopsy, but follicular adenomas and carcinomas have similar cytological appearance, with

diagnosis of malignancy requiring demonstration of capsular or vascular invasion in

paraffin sections. Follicular tumours are thus reported initially as “follicular neoplasms”

and cannot be characterised as benign or malignant without histological examination. All

follicular neoplasms should be excised unless there is clear evidence that the nodule is

hyperfunctioning.

Atypical cytology is found in 20% of specimens, and about a third of these lesions are

found to be malignant when excised and examined histologically.2

Indications for thyroid surgery thus include malignant or atypical cytology, follicular

neoplasm, and failure to obtain a diagnostic sample. In the future, molecular genetic

studies of aspirated material (eg, for the RET/PTC gene rearrangements often found in

papillary cancer) may offer more precise diagnosis.

This patient was also underwent thyroid function test, FNAC and Ultrasound scan of the

neck. Thyroid isotope scan is not widely available in Sri Lanka and puts the patient into

unnecessary exposure of radiation. It is not indicated in this patient as he was euthyroid.

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Ultrasound is cheaper, widely available and noninvasive method, but the main drawback

is that the findings are operator dependant. This patients USS clearly showed that the

lump was solitary rather than a dominant nodule of a multinodular goiter. Cytology report

showed a follicular neoplasm and had the same problem of differentiating follicular

adenoma from follicular carcinoma.

Management of suspicious thyroid nodule

The management of any suspicious thyroid nodule is hemithyroidectomy. That is to do

total lobectomy and Isthmusectomy. This is to prevent the difficulty in accessing the same

side if total thyroidectomy is indicated after histology report. This procedure is curative in

solitary papillary carcinomas < 1 cm and minimally invasive follicular carcinomas.2 For

these reasons a total lobectomy and a isthmusectomy was planned in this patient.

Summary of management of a suspicious thyroid nodule

Primary Management of follicular carcinoma

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The management of follicular carcinoma is discussed briefly as the patients initial

diagnosis was follicular neoplasm.

The most surgeons recommend a total thyroid lobectomy with isthmusectomy for

“follicular cell neoplasms.” When the lesion is benign, no further therapy is needed.

When the tumor is malignant, completion (total) thyroidectomy may be indicated to

facilitate subsequent radioactive iodine (RAI) scanning and therapy. Some clinicians use

RAI to ablate the residual lobe, in as much as follicular carcinomas are rarely bilateral.

When follicular carcinoma is minimally invasive and characterized only by limited

capsular invasion, lobectomy is likely to provide definitive therapy. When more extensive

capsular or vascular invasion is present, completion total thyroidectomy or RAI ablation

is warranted. Risk-group classification (AMES, AGES, or MACIS) is also considered by

many surgeons as a criterion before completion thyroidectomy is recommended 1.

Surgery

Preparation for surgery

Informed consent should be obtained from all patients after full discussion; the operating

surgeon should normally obtain the consent. The surgeon will be a member of the Multi

disciplinary team (MDT) with specific training and experience of endocrine surgery. The

specific complications of thyroid surgery should be discussed with the patient as well as

those complications which can occur in any surgical procedure; this should be recorded in

the notes. Thromboembolism prophylaxis should be used in all cases in the form of

graduated compression hose (TED stockings) and peri-operative calf compression

devices. It is usually felt to be inappropriate to use heparin preparations in routine thyroid

surgery. Vocal cords are examined prior to surgery. This is particularly important for

medico-legal purpose. As in this particular patient, It is indicate in patient with hoarseness

of voice to assess the integrity of the recurrent laryngeal nerve prior to surgery.

Surgical procedure

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The surgical options available are open surgery and minimally invasive video assisted

surgery. Minimally invasive surgery is not suitable for large tumours. It is usually done

for tumours less than 1 cm. The main drawbacks of this procedure are the lack of

expertise, equipments and longer operative time.

This patient was initially diagnosed of having follicular neoplasm. Per-operatively the

tumour was found to be more aggressive and total thyroidectomy was done. Some

expertises advocate near total thyroidectomy in view of lesser complication of RLN and

parathyroid damage.

Total thyroidectomy is beneficial, because

Multifocal disease occurs in opposite lobe in 35-80%.

There is reduce local recurrence or progression in to undifferentiated tumour

It facilitates ablation with radioiodine

Serum thyroglobulin can be use as a tumour marker

In experience hand the morbidity of total thyroidectomy is low (<3%)

The damage to recurrent laryngeal nerve and parathyroid can be minimized or

avoided if one stick to the following methods.

Routinely identify and preserve the recurrent laryngeal nerve before ligating the

pedicles

Always stay on the thyroid capsule

Use titanium clips and bipolar diathermy

Leave the tiniest fraction of thyroid tissue at the hilum (ligamentum of Berry)

If parathyroids are removed accidentally implant them in sternocleidomastoid

muscles

Use Magnifying Loupes

EMG monitoring of the RLN

During thyroidectomy of this patient, RL nerve and parathyroids were identified at the

beginning. It can be found usually deep to the branches of the inferior thyroid artery by

looking for “tooth paste sign”(There is a small vessel travelling along with the nerve

which looks like a well branded tooth paste). However one must be careful about the

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anatomical variation of the nerve such as nerve travelling superficial to artery and in

between the branches of the artery. Some surgeons never look for the nerve and avoid

damage to by dissecting very closed to the gland.

This patient the branches of the inferior thyroid artery were ligated individually rather

than the main stem of the artery. This reduces the risk of ischemic damage to the

parathyroids. In Sri Lanka surgeons rarely use loupes (magnifying glasses) during thyroid

surgery and EMG monitoring of the RLN not practice here either.

Post operative management of thyroidectomy

The patient should be managed in propped up position. Closed monitoring should be done

to identify early postoperative complications. It is necessary to nurse the patient in acute

area of the ward where it is very close to, the nurse’s station. It is important to keep a clip

removal or a suture remover next to the bed. Provided that pain is adequately relieved,

the thyroid surgery is well tolerated. Pain relief can be given in the form of intramuscular

opioids or oral NSAIDS. Oral fluids can be started on the first post operative day. Steam

inhalation nebulization is important part of management in view of preventing atelectasis

and chest infection. Sore throat lasts for about 24 hours. Post operative antibiotics are

unnecessary as it is a clean surgery. Clips or sutures can be removed on the second post

operative day.

Complications of surgery

Haemorrhage – tension haematoma develops deep to the cervical fascia usually

due to slippage of ligature4. It may be due to oozing from the thyroid remnant.

Rarely it may be necessary to open the wound at the bed side before taking the

patient to theatre to evacuate the haematoma and secures the bleeder. To prevent

this complication, it is always necessary to secure all bleeders and bring back the

blood pressure to preoperative values before closure of the wound. Placing a drain

does not guarantee that it will prevent this complication as the drains can get

blocked due to clots.

Respiratory obstruction – In most cases it is due to laryngeal oedema as a sequel

of tense haematoma. However trauma to larynx during intubation and surgery may

be contributory factors. Bilateral recurrent laryngeal nerve paralysis will not cause

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immediate postoperative respiratory obstruction unless laryngeal oedema is also

present.4 The trachoea should be immediately intubated. It is important to know

that relieving the haematoma does not immediately relieve the air way

obstruction.

RLN damage – Hoarseness in the immediate postoperative period is likely to be

due to recurrent nerve damage. This may be unilateral or bilateral, transient or

permanent. Transient can occur in about 3% of the nerves at risk recover in about

3 weeks to 3 months 5. This complication is unlikely if the nerve was identified at

operation. It is important to assess the vocal cords preoperatively as well as before

discharge of the patient.

Damage to external laryngeal nerve – This complication is usually ignored or

fails to recognize during postoperative period. It can cause voice weakness or

fatigue, mild hoarseness and loss of voice range.

Parathyroid insufficiency – This may be due to removal of parathyroid or

damage to the arteries supplying it. Most cases present dramatically 2-5 days after

the operation. If the symptoms are immediate and severe intravenous calcium is

necessary and may need oral vitamin D and calcium supplement. It is necessary to

screen the patient with total thyroidectomy at 4-6 weeks for hypocalcaemia.

Hypocalcaemia beyond 6 month is likely to be permanent.

This patient was also managed according to the above protocol. His post operative period

was uneventful and he recovered with no complications.

Post operative Staging

Proper staging can only be done after the histological assessment of the thyroid specimen.

Widely used staging system is American Joint Committee on cancer.

(Table 1) TNM Status

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(Table 2)

This patient’s histology report showed a medullary carcinoma which was totally different

from the preoperative diagnosis. The diagnosis of “sporadic” medullary carcinoma may

be suspected on the basis of specific cytologic features on FNA. Because these features

often are not sought or recognized at the time of FNA, the diagnosis is usually first made

at the time of surgical removal of a thyroid nodule.1

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The TNM staging of this patient’s Medullary carcinoma was T2 N0 M0. AJCC staging was

II. However, it was difficult to give correct staging system as the lymph node dissection

has not been done.

Risk-group assignment

The most important risk factors for medullary carcinoma (MTC) tumor recurrence and

cause-specific mortality are age at time of initial assessment, tumor size, presence of

extrathyroid invasion, and presence of distant metastatic lesions1. Initial nodal metastatic

disease in MTC predicts a higher risk of recurrence and death. Complete tumor resection

(absence of gross residual tumor) of MTC predicts a more favorable outcome 1.

No of scoring systems have been devised Eg.

AGES System - Age, Tumour Grade, Extent, Size

AMES system - Age, Metastasis, Extent, Size

MACIS scoring system - Metastasis, Age, Completeness of resection, Invasion,

Size

This patient’s prognosis is better as there was no evidence of distant metastasis and

minimal extrathyroidal invasion. Though there was no evidence of nodal extension,

presence of such nodes at initial diagnosis would have drastically reduced the prognosis.

MEDULLARY THYROID CARCINOMA

Introduction

Medullary carcinoma constitutes 6 to 8% of thyroid cancers, of which approximately 75%

are sporadic and 25% are hereditary. MTC represents a malignant transformation

of neuroectodermally derived parafollicular C cells. Therefore, its behavior and

management differ from these features described for well-differentiated follicular derived

thyroid carcinomas 3.

MTC has a genetic association with multiple endocrine neoplasia (MEN) type 2A and 2B

syndromes, but it has an inheritable non-MEN mode of transmission.

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Outcome depends on extent of disease, nature of tumor biology, and overall efficacy of

surgical treatment. Advances in genetic testing in the past few years have revolutionized

the management of this disease.

Pathophysiology: MTC is usually diagnosed on physical examination as a solitary neck

nodule, and early spread to regional lymph nodes is common. Distant metastases occur in

the liver, lung, bone, and brain.

Sporadic MTC usually is unilateral. In association with MEN syndromes, it always is

bilateral and multicentric. MTC typically is the first abnormality observed in both MEN

2A and 2B syndromes.

In addition to producing calcitonin, MTC cells can produce several other hormones,

including corticotropin, serotonin, melanin, and prostaglandins; moreover, paraneoplastic

syndromes (eg, carcinoid syndrome, Cushing syndrome) can occur in these patients.

Mutations in the ret protooncogene, a receptor protein tyrosine kinase encoded on

chromosome 10, have been recently classified into discrete subtypes; prophylactic

thyroidectomy can now be offered to specific types of patients with this genetic

abnormality.

Histologic Findings

Grossly, MTC resembles a well-circumscribed off-white nodule with a rough texture.

Microscopically, it contains nests of round or ovoid cells. A fibrovascular stroma is

usually intercalated between cells. Sometimes, amyloid material, consisting of calcitonin

prohormone, may occur in the MTC stroma. Perhaps most importantly,

immunohistochemical diagnosis of MTC can be made by demonstrating calcitonin using

radioactive calcitonin antiserum against MTC cells.

This particular patient did not have any family history of medullary carcinoma, thyroid

carcinomas or evidence of MEN syndrome. He had unilateral disease involving one lobe

only. So these features are more suggestive of a sporadic medullary carcinoma.

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Sporadic Medullary Carcinoma

Fewer than 1 in 200 clinically apparent solitary thyroid nodules may harbor a medullary

carcinoma1.

The diagnosis of sporadic medullary carcinoma may be suspected on the basis of

characteristic cytologic features on FNA and immunostaining for calcitonin and

confirmed by a high preoperative serum calcitonin level. Because these features often

are not sought or recognized at the time of FNA, the diagnosis is usually first made

at the time of surgical removal of a thyroid nodule. Although studies have suggested

that, in the evaluation of a thyroid nodule, the routine measurement of serum calcitonin is

a cost-effective and important technique to avoid missing this potentially lethal tumor, not

all clinicians agree that screening calcitonin is useful1. Calcitonin should be measured in

the setting of a thyroid biopsy specimen with atypical features or an apparently anaplastic

or poorly differentiated tumor in a young person. Suggestive cytologic features should

prompt a request for calcitonin immunostaining of the biopsy specimen.

In medullary thyroid cancer, an abnormal CEA level heralds advanced disease.

Carcinoembryonic antigen levels greater than 30.0 ng/mL indicate central and lateral

(ipsilateral) lymph node metastases, whereas CEA levels greater than 100.0 ng/mL

signify lateral (contralateral) lymph node metastases and distant metastasis.7

Ultrasonography may reveal bright echogenic foci (corresponding to calcium).

Abnormal lymph nodes may be seen as well 1, prompting a calcitonin measurement

preoperatively. If medullary carcinoma is suspected preoperatively, the extent of the

disease may be evaluated by ultrasonography, CT, or MRI of the neck and CT of the

chest and abdomen.

The preoperative calcitonin level correlates well with tumor bulk, nodal and distant

metastatic involvement, and postoperative calcitonin normalization 1. In the absence of a

family history of MTC, usually no clues distinguish MTC from other thyroid nodules.

Chronic diarrhea, lichen amyloidosis, or features suggestive of ectopic ACTH

82


(adrenocorticotropic hormone) syndrome are rarely present. When MTC is diagnosed or

suspected, preoperative screening for pheochromocytoma is imperative.

Surgical treatment of MTC should include total thyroidectomy, central compartment

lymph node dissection, and ipsilateral (unilateral) modified radical neck dissection1.The tumor is staged in accordance with the AJCC system (see discussion of staging

systems earlier in these guidelines), in which data are recorded about tumor size, lymph

node involvement, and distant metastatic lesions.

Risk factors for recurrence and death include tumor size, preoperative calcitonin level,

advanced age, extrathyroid tumor extension, progression of cervical nodal disease to the

mediastinum, extranodal tumor extension, and incomplete tumor excision.

Serum calcitonin levels should be measured 8 to 12 weeks postoperatively to assess the

presence of residual disease. The presence of an elevated but stable calcitonin level post-

operatively may be managed conservatively. Progressively rising levels should trigger

imaging for further staging. In the absence of recurrent symptoms, appropriate intervals

are 6–12 months. Life-long follow-up is recommended as tumour can reccur many years

later.6

If preoperative staging had not been performed, residual postoperative calcitonin should

prompt a search for locally resectable disease in the neck as well as metastatic disease in

the bones, lungs, or liver. For residual local disease, ultrasonography of the neck is the

most sensitive and cost-effective procedure.

The search for metastatic disease may include CT and MRI scans, scanning with

sestamibi, radioiodinated metaiodobenzylguanidine, octreotide (indium pentetreotide),

and 131I anti-CEA antibody. 99mTc methylene diphosphonate, 99mTc

dimercaptosuccinic acid, and 201Tl have also been used with variable success 1.

Unfortunately, localization of residual disease is often difficult or impossible when the

calcitonin level is less than 1,000 pg/mL—an indication of a relatively small residual

tumor burden. Additional methods of localizing residual disease include selective venous

83


sampling of the neck and viscera for calcitonin and laparoscopic liver biopsy. Identifying

distant disease may be important for obviating extensive neck dissection in a

curative attempt1.The behavior of residual disease may vary from indolent to aggressive 1.

Tumor pathologic features, such as absent amyloid staining, low density of calcitonin

staining, or aneuploidy, and production of other neuroendocrine products may correlate

with a worse prognosis but are of uncertain use in planning subsequent clinical

management1. Physicians have variously advocated either aggressive surgical removal of

residual cervical and mediastinal disease or conservative management.

Adjuvant therapy, including external beam radiotherapy and chemotherapy, is of

unproven benefit but is often used when the patient has a potential risk of either

obstructive symptoms or relentless cancer growth. Experimental therapy with high-dose

131I anti-CEA antibody is currently under investigation. Activating mutations in a

tyrosine kinase receptor gene are present in the majority of MTCs, and experience with

tyrosine kinase inhibitors and other agents in the setting of clinical trials is critical for the

identification of effective systemic treatment. 8Most authorities advocate careful

observation and conservative management, even in the face of known metastatic disease,

because of the relative lack of efficacy of currently available adjuvant therapy.

Pathologically, the presence of bilateral thyroid disease, including staining for C-cell

hyperplasia, should be sought as a possible reflection of a newly diagnosed hereditary

Form of the disease.

Because somatic mutations of the RET proto-oncogene are frequently present in sporadic

disease, genetic analysis of the tumor is not warranted. Search for a germline mutation,

however, is the most costeffective means of identifying new families at risk1.

It is important to recognize the heritable form of MTC because of the risk of other

tumours in the individual and in the family. Early recognition and prophylactic surgery in

MEN-2 are effective in reducing both mortality and morbidity. Lack of family history

does not exclude heritable disease. The disease may not be apparent in relatives because

of ‘skipped’ generations; or an isolated case may be the start of a new family. Inherited

MTC without other endocrinopathies also occurs. It is inherited in similar ways but tends

to be more indolent than other forms of MTC. Because of the rarity of MTC and the

84


complexity of genetic investigation and management, cases should be managed by a

specialist clinical service.

When considering this patient, it is important to discuss whether he need further surgery.

According to the current evidence at least central node neck dissection is the minimum,

but secondary surgery is sometimes not accepted by the patient and found to be difficult

to perform. However this procedure will give the lymph node status which is very

important for the prognosis of the patient.

As preoperative calcitonin level has not been done, it is difficult to get a base line value.

However it is necessary to do calcitonin level at least postoperatively, because the

presence of an elevated but stable calcitonin level post-operatively can be managed

conservatively and progressively rising levels should trigger imaging for further staging.

Response to primary surgery should be assessed clinically as well as by clacitonin levels.

In the absence of recurrent symptoms, appropriate intervals are 6–12 months.

There is no need to give suppressive dose of thyroxin because the medullary carcinoma is

not dependant on TSH. So the plan was to reduce the thyroxin level to therapeutic dose

and maintain it with regular thyroid function test. Though there was no family history

suggestive of MEN syndrome it is necessary to exclude pheochromocytoma.

There are meager facilities for genetic studies in Sri Lanka. Ideally the patient and the

family members should be screened for RET protooncogene.

85


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1. Thyroid Carcinoma Task Force. AACE/AAES Medical/Surgical Guidelines for

Clinical Practice: Management of thyroid carcinoma. Endocrine practice,2001

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2. Mackenzie EJ, Mortime RM. Thyroid nodules and thyroid cancer. eMJA, 2004; 180

(5): 242-247.

3. Konstantakos AK, Graham DJ. Thyroid, Medullary carcinoma. www.emedicine.com.

2006,april 18.

4. Zygmunt H Krukowski . The thyroid gland and the thyroglossal tract. In Russel,

RCG, Williams NS, Bulstrode CJK(eds.) . Baley & Love’s Short Practice of Surgery,

24th edn. London Oxford University Press, 2004, p 776-804.

5. Farndon JR, Fowler CA. Thyroid Gland. In Kurk RM. General Surgical Operations,

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6. British thyroid association: Guidelines for the management of thyroid cancer in

adults. Royal college of physician; 2002 march.

7. Machens, A, Ukkat J, Hauptmann S, Dralle H. Abnormal carcinoembryonic antigen

levels and medullary thyroid cancer progression: a multivariate analysis. Arch Surg.

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12. Al-Rawi M, Wheeler MH. Medullary thyroid carcinoma--update and present

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13. Quayle FJ, Moley JF. Medullary thyroid carcinoma: management of lymph node

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14. Hamy A, Pessaux P, Mirallié E, Mucci-Hennekinne S, Gibelin H, Mor-Martinez C, de

Calan L, Ronceray J, Kraimps JL. Central neck dissection in the management of

sporadic medullary thyroid microcarcinoma. Eur J Surg Oncol. 2005 Sep;31(7):774-

7.

15. Mirallié E, Iacobone M, Sebag F, Henry JF.Results of surgical treatment of sporadic

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J Surg Oncol. 2004 Sep;30(7):790-5.

16. Yen TW, Shapiro SE, Gagel RF, Sherman SI, Lee JE, Evans DB. Medullary thyroid

carcinoma: results of a standardized surgical approach in a contemporary series of 80

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17. Franc S, Niccoli-Sire P, Cohen R, Bardet S, Maes B, Murat A, Krivitzky A,

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