Lymph node metastasis in neck (secondaries in cervical lymph nodes)

DIAGNOSIS AND INVESTIGATIONSBy Somu VenkateshRoll Number 118Final year part 2

DIAGNOSIS OF SECONDARIES IN NECK LYMPH NODES

Secondaries in the Neck lymph nodes

They are divided into 3 types

1.Secondaries in the Neck with Known Primary

2.Secondaries in the Neck with Clinically Unidentified Primary

3.Secondaries in the Neck with an Occult Primary

1.Secondaries in the Neck with Known Primary

• Here secondaries are present and primary has been identified clinically in the oral cavity, pharynx, larynx, thyroid or other areas.• Investigations: Biopsy from the primary and FNAC from the secondaries • Treatment:• Primary is treated by -Curative Radiotherapy or Surgery(wide excision).• Secondaries, when mobile are treated by radical lymph

node block dissection in the neck

2.Secondaries in the Neck with Clinically Unidentified Primary

• Hard neck lymph nodes are secondaries, but primary has not been identified clinically.• Investigations: FNAC from the secondaries Then search for the primary is done by various

investigations. They area) Panendoscopyb) Surveillance biopsyc) FNAC of thyroid and suspected areasd) CT scan.

2.Secondaries in the Neck with Clinically Unidentified Primary

a. Panendoscopy - Nasopharyngoscopy - Laryngoscopy - Oesophagoscopy - Bronchoscopy.b. Surveillance biopsy : Blind biopsies are taken fromFossa of RosenmullerLateral wall of pharynxPyriform fossaTonsillar bedBase of tongueSubglottic region (larynx)

2.Secondaries in the Neck with Clinically Unidentified Primary

c. FNAC of thyroid and suspected areasd. CT scan(Note: Surveillance biopsy is done to reveal unknown primary in 15% of cases of secondaries in neck. If this surveillance biopsy is negative, then ipsilateral tonsillectomy may be needed.)

TreatmentPrimary is treated by Curative radiotherapy.Secondaries in the neck is treated by Radical Neck Dissection.

3.Secondaries in the Neck with an Occult Primary• Occult = hidding from view

• Secondaries in the neck lymph nodes are confirmed by FNAC, but primary has not been revealed clinically and by any available investigations.

• Occult primary : When all the investigations do not show any evidence of primary.

• Reasons for primary lesion being occultToo small a primary to detect;Possibility of immunological spontaneous regression of primary and Inability of the present diagnostic tools to detect the primary.

3.Secondaries in the Neck with an Occult Primary• Histologically secondaries in neck with occult primary may be

of squamous cell carcinoma or of nonsquamous cell carcinoma, i.e., adenocarcinoma/poorly differentiated tumours (lymphoma/sarcoma/melanoma).

• In upper and midcervical region 80% are due to squamous cell carcinoma.

• In lower cervical and supraclavicular region 40% can be adenocarcinomas.

• Common sites of primary here (for adenocarcinoma) are thyroid, breast, gastrointestinal tract, salivary glands, lungs, prostate and kidney.

3.Secondaries in the Neck with an Occult Primary• 70% of occult nodes occur in jugulodigastric group.

• Differential diagnosis for secondary with occult primary is lymphoma and primary branchogenic carcinoma.

3.Secondaries in the Neck with an Occult PrimaryInvestigations for seconday tumour FNAC is the tool to confirm the occult secondary. Open biopsy (if FNAC is inconclusive)-incision/excisionOpen biopsy helps in high suspects of lymphomas or poorly

differentiated carcinomas .It facilitates tissue study, immunohistochemistry, and special

stains.Many studies prove that risk of seedling, survival and prognosis

will not alter by open biopsy.But at present it is proposed only when FNAC fails or special

methods are mandatory to type the disease.After open biopsy, frozen section confirmation and immediate

neck dissection has to be done.

3.Secondaries in the Neck with an Occult Primary Immunoperoxidase staining is the most commonly

used on FNAC specimen or formalin fixed paraffin tissue using monoclonal or polyclonal antibodies.

Immunoperoxidase mainly used in lymphomas/neuroendocrine tumours

Electron microscopy is superior to immunohistochemistry as ultrastructure details can be assessed. But it is costly.

Chromosomal analysis for tumour specific genes is used in B, T and germ cell lymphomas.

3.Secondaries in the Neck with an Occult PrimaryInvestigation for occult primary• CECT is the investigation of choice to look for primary

• FNAC of node/open biopsy to confirm

• Other methods are – MRI , triple endoscopy, surveillance biopsy, FNAC of thyroid, ipsilateral tonsillectomy if surveillance biopsy and other methods are negaive

3.Secondaries in the Neck with an Occult PrimaryTreatmentInitially the SECONDARIES in the neck are treated by Radical

Neck Dissection, then regular follow-up is done (at 3 monthly intervals) until the primary reveals.

Once PRIMARY is revealed it is confirmed by biopsy and treated accordingly, either by Curative Radiotherapy or by Wide Excision depending on location of revealed primary.

PrognosisThis type is usually less aggressive and has got better

prognosis.

Nodal staging in secondaries

• Nx – nodes cannot be assessed

• No – no nodal metastasis

• N1 – single node same side <3 cm

• N2a – single node same side 3-6cm

• N2b – multiple nodes same side <6cm

• N2c – bilateral /contralateral nodes < 6cm

• N3 – node > 6 cm

INVESTIGATION FOR SECONDARIES IN

NECK

Investigations for secondaries in neck

FNAC of secondary: open incision biopsy is not advised here. It destroys the fascial

barriers and causes the spread of tumours faster and earlier into next level nodes or other soft tissues. Eventual neck dissection technically becomes difficult. Recurrence rate in neck will be higher after open biopsy.

If FNAC of node and all investigations for primary become negative, then open biopsy of node following confirmation with frozen section and immediate neck dissection is undertaken. In such situation if neck dissection is delayed after open biopsy confirmation, chances of cure will be reduced.

FNAC

Investigations for secondaries in neckBiopsy from primary : Incision biopsy is the choice here.Blind biopsies from suspected areas.Panendoscopy with examination under anaesthesia.CT scan is to see the base of skull, paranasal sinuses,

nasopharynx, extension of primary tumour/secondary deposites; CT scan of chest and abdomen.

Chest X-ray to visualise primary or secondaries in case melanomas or mediastinal nodes.

MRI scan or PET scan in conjunction with CT scan or MRI. MRI identifies soft tissue extension/changes; guided primary biopsy is possible; extension into bone is identified.

CT chest and abdomen in case of infraclavicular primaries or to assess nodes.

Differential diagnosis• Lymphomas

• Tuberculous lymphadenitis

• Nonspecific lymphadenitis

• HIV

• Chronic lymphatic leukaemia

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