5. nasopharyngeal carcinoma

Nasopharyngeal CarcinomaDr. Krishna Koirala2016-05-20

IntroductionNasopharyngeal carcinoma is a non - lymphomatous squamous-cell carcinoma that occurs in the epithelial lining of the nasopharynxIt frequently arises from the pharyngeal recess (fossa of Rosenmller) posteromedial to the medial crura of the eustachian tube opening in the nasopharynx

EpidemiologyAccounts for 85% adult nasopharyngeal malignancies and 30% pediatric nasopharyngeal malignanciesRace : Common in Chinese & North African people Sex : Male preponderance of 3:1 Age : Bimodal presentation with Small peak at 15-25 yrs and a large peak at 55-65yrsGross : Proliferative, Ulcerative & Infiltrative types Histology : 85% Squamous cell carcinoma, 10% Lymphomas, 5% Mixed

EtiologyGenetic Commonest in Southern Chinese population ( Mongoloid race) HLA A ,B and DR loci situated on the short arm of chromosome 6 Viral : Epstein-Barr VirusEnvironmental Exposure to nitrosamines (dry salted fish), polycyclic hydrocarbons (smoke from incense & wood)Smoking , chronic nasal infection, poor ventilation of nasopharynx

W.H.O. Classification (Histological)Type 1: Keratinizing squamous cell carcinoma Type 2: Non-keratinizing (transitional) carcinoma Type 3: Undifferentiated (anaplastic) carcinoma

Clinical Features1. Neck swelling (60%)Lateral retropharyngeal LN of RouviereB/L, enlarged jugulodigastric, upper & middle deep cervical nodes and posterior triangle nodes 2. Nasal (40%)Blood stained nasal mucus, epistaxis, nose block, foul smelling nasal discharge 3. Otologic (30%) : Conductive deafness, tinnitus

4. Ophthalmologic (20%) Diplopia & ophthalmoplegia (involvement of CN III, IV, VI), Proptosis (orbit invasion) & blindness (involvement of CN II)5. Neurologic (20 %)Jugular foramen syndrome: CN IX, X, XI involved by lateral retropharyngeal lymph node Horner's syndrome: sympathetic chain involvement

6. Severe Headache Skull base erosion 7. Trotter's triad Conductive deafness: Eustachian Tube block Ipsilateral temporo -parietal neuralgia: Trigeminal nerve involvement Ipsilateral palatal paralysis: Vagus nerve damage8. Distant metastasisBone, lungs & liver

Investigations1. Nasopharyngoscopy & Diagnostic Nasal EndoscopyMass seen in nasopharynx at fossa of Rosenmller 2. Nasopharyngeal tumor biopsy: blind /under vision3. F.N.A.C. of neck node: done in occult primary 4. C.T. scan head & neckTumor extentSkull base erosion Cervical lymph node metastasis

5. M.R.I. head & neck: for intracranial extension.6. Tests for metastasesC.T. chest and abdomen, bone scan, P.E.T. scan, liver function tests7. Serologic tests Immuno-fluorescence for IgA antibodies to Viral Capsid Antigen, Ig G antibodies to Early Antigen

Diagnostic Nasal Endoscopy

Computerized Tomogram Scan

CT scan: retropharyngeal node

CT scan: Infratemporal fossa & orbit involvement

CT scan: Sella involvement

Magnetic Resonance Imaging

M.R.I.: intracranial extension

Endoscopic Biopsy

Whole body bone scan

Positron Emission Tomography

T.N.M. stagingT1 = confined to nasopharynxT2 = soft tissue involvement in oropharynx or nasal cavity or Parapharyngeal spaceT3 = invasion of bony structures or P.N.S. T4 = intracranial, involvement of orbit, cranial nerves, infratemporal fossa, hypopharynx

N0 = no evidence of regional lymph nodes N1 = unilateral N2 = bilateral (Both are above supraclavicular fossa & < 6 cm) N3 = > 6 cm or in supraclavicular fossa

M0 = no evidence of distant metastasisM1 = distant metastasis present

T.N.M. stagingStage I = T1 N0 M0 Stage II = T2 or N1 M0Stage III = T3 or N2 M0Stage IV = T4 or N3 or M1

Treatment modalities 1. Teletherapy or External beam radiotherapy 2. Brachytherapy 3. Chemotherapy 4. Surgery 5. Immunotherapy against E.B.V. 6. Vaccination against EBV: experimental

External beam irradiation2 lateral fields: nasopharynx, skull base & upper neck sparing temporal lobe, pituitary & spinal cord1 anterior field: lower neck; sparing spinal cord & larynx

BrachytherapyUsed for small tumor, residual or recurrent tumorInterstitial: Radioactive source (Radium, Iridium, Iodine, Gold) inserted into tumor tissueIntracavitary: Radioactive source placed inside the catheter or moulds & inserted into nasopharynxHigh dose rate (HDR): High intensity radiation delivered with precision under computer guidance

Interstitial Brachytherapy

Intracavitary Brachytherapy

High Dose Rate Brachytherapy

ChemotherapyDrugs used1. Cisplatin 2. 5-Fluorouracil Indications1. Radiation failure 2. Palliation in distant metastasis

Surgery1. Nasopharyngectomy, Cryosurgery : for residual or recurrent tumor2. Radical neck dissection: for radio-resistant neck node metastasis3. Palliative debulking: for T4 tumors4. Myringotomy & grommet insertion: for persistent otitis media with effusion

Radical neck dissection & Interstitial Brachytherapy

Treatment ProtocolT1 = External Radiotherapy (6500 c Gy) T2 = External Radiotherapy (7000 c Gy)T3 & T4 = Radiotherapy + Chemotherapy Brachytherapy / Salvage surgery if required N0 = External Radiotherapy (5000 c Gy)N+ = External Radiotherapy (6000 cGy) + Chemotherapy

PrognosisW.H.O. Type 2 & 3 carcinomas have good response to radiotherapy & better survival rates Average 5 year survival rates for treated patientsStage I = 95 100 %Stage II = 60 80 %Stage III = 30 60 %Stage IV = 20 30 %