1、Nasopharygeal CarcinomaIntroduction Rare in the US, more common in Asia High index of suspicion required for early diagnosis Nasopharyngeal malignancies SCCA (nasopharyngeal carcinoma) Lymphoma Salivary gland tumors SarcomasAnatomy Anteriorly - nasal cavity Posteriorly - skull base and vertebral bod
2、ies Inferiorly - oropharynx and soft palate Laterally - Eustachian tubes and tori Fossa of Rosenmuller - most common locationAnatomy Close association with skull base foramen Mucosa Epithelium - tissue of origin of NPCStratified squamous epitheliumPseudostratified columnar epithelium Salivary, Lymph
3、oid structuresEpidemiology Chinese native Chinese immigrant North American native Both genetic and environmental factors Genetic HLA histocompatibility loci possible markersEpidemiology Environmental VirusesEBV- well documented viral “fingerprints” in tumor cells and also anti-EBV serologies with WH
4、O type II and III NPCHPV - possible factor in WHO type I lesions Nitrosamines - salted fish Others - polycyclic hydrocarbons, chronic nasal infection, poor hygiene, poor ventilationClassification WHO classes Based on light microscopy findings All SCCA by EM Type I - “SCCA” 25 % of NPC moderate to we
5、ll differentiated cells similar to other SCCA ( keratin, intercellular bridges)Classification Type II - “non-keratinizing” carcinoma 12 % of NPC variable differentiation of cells ( mature to anaplastic) minimal if any keratin production may resemble transitional cell carcinoma of the bladderClassifi
6、cation Type III - “undifferentiated” carcinoma 60 % of NPC, majority of NPC in young patients Difficult to differentiate from lymphoma by light microscopy requiring special stains & markers Diverse groupLymphoepitheliomas, spindle cell, clear cell and anaplastic variantsClassification Differences be
7、tween type I and types II & III 5 year survivalType I - 10% Types II, III - 50% Long-term risk of recurrence for types II & III Viral associationsType I - HPVTypes II, III - EBVClinical Presentation Often subtle initial symptoms unilateral HL (SOM) painless, slowly enlarging neck mass Larger lesions
8、 nasal obstruction epistaxis cranial nerve involvementClinical Presentation Xerophthalmia - greater sup. petrosal n Facial pain - Trigeminal n. Diplopia - CN VI Ophthalmoplegia - CN III, IV, and VI cavernous sinus or superior orbital fissure Horners syndrome - cervical sympathetics CNs IX, X, XI, XI
9、I - extensive skull base Clinical Presentation Nasopharyngeal examination Fossa of Rosenmuller most common location Variable appearance - exophytic, submucosal NP may appear normal Regional spread Usually ipsilateral first but bilateral not uncommon Distant spread - rare (3%), lungs, liver, bonesRad
10、iological evaluation Contrast CT with bone and soft tissue windows imaging tool of choice for NPC MRI soft tissue involvement, recurrences CXR Chest CT, bone scans Laboratory evaluation Special diagnostic tests (for types II & III) IgA antibodies for viral capsid antigen (VCA) IgG antibodies for ear
11、ly antigen (EA) Special prognostic test (for types II & III) antibody-dependent cellular cytotoxicity (ADCC) assayhigher titers indicate a better long-term prognosis CBC, chemistry profile, LFTsStaging Variety of systems used Am Jt Comm for Ca Staging International Union Against Ca Ho System Unique
12、NPC prognostic factors often not considered and similar prognosis between stagesStaging Neel and Taylor System Extensive primary tumor +0.5 Sxs present 2 months before dx - 0.5 Seven or more sxs +1.0 WHO type I +1.0 Lower cervical node dx +1.0 - ADCC assay titer considered if availableStaging Stage
13、A = 2Treatment External beam radiation Dose: 6500-7000 cGy Primary, upper cervical nodes, pos. lower nodes Consider 5000 cGy prophylactic tx of clinically negative lower neck Adjuvant brachytherapy mainly for residual/recurrent diseaseTreatment External beam radiation - complications More severe whe
14、n repeat treatments required Includexerostomia, tooth decayETD - early (SOM), later (patulous ET)Endocrine disorders - hypopituitarism, hypothyroidism, hypothalamic disfunctionSoft tissue fibrosis including trismusOphthalmologic problemsSkull base necrosisTreatment Surgical management Mainly diagnos
15、tic - Biopsy consider clinic bx if cooperative patient must obtain large biopsy clinically normal NP - OR for panendo and bx Surgical treatment primary lesion regional failure with local control ETD Treatment Surgical management Primary lesion consider for residual or recurrent disease approachesinf
16、ratemporal fossa transparotid temporal bone approachtransmaxillarytransmandibulartranspalatalTreatment Surgical management Regional disease Neck dissection may offer improved survival compared to repeat radiation of the neck ETD BMT if symptomatic prior to XRT Post XRTobservation period if symptoms
17、not severeamplification may be more appropriateTreatment Chemotherapy Variety of agents Chemotherapy + XRT - no proven long term benefit Mainly for palliation of distant disease Immunotherapy Future treatment? Vaccine?Conclusion Rare in North America, more common in China 40% overall survival at 5 years Complete H&P, careful otologic, neurologic, cervical and NP exams Three WHO types - all from NP epithelium Types II, III - better prognosis, EBV assoc. Treatment is primarily XRT
