Pathology of the Head and Neck

Neck Cysts, Metastasis, Dissection Chapter 9 277Fig. 9.13. Metastatic cystic tonsillar crypt carcinoma, resemblinga branchial cleft cyst. Inset: high power view of non-keratinisingcarcinoma, human papilloma virus type 16 positiveFig. 9.14. Cytokeratin 7 positive metastatic tonsillar basaloid carcinomain a cervical lymph nodeTable 9.4. Immunohistochemical approach to metastasis of unknown primary tumour. (Extracted from references [19, 21, 29 ,40, 56,66, 83, 84, 94])Cytokeratin-positiveKeratinizing squamous cell carcinoma CKs 5/6, 7 and 20Non-keratinizing squamous carcinoma CKs 5/6, 7 and 20EBV, HPV 16Adenocarcinoma CKs 7, 20TTF-1ThyroglobulinFemales: GCDFP-15, WT-1, CA 125Males: PSA .Young males: AFP, HCGUndifferentiated carcinoma CKs 7 and 20SynaptophysinChromograninEBVCytokeratin-negativeVarious tumoursS-100 proteinHMB 45Melan ADesminLymphoma markersgastrointestinal tract, or prostate. In the upper and middleneck, on the other hand, the primary lesions are locatedin the sinonasal tract and salivary glands. Only incases of thyroid carcinoma or prostate carcinoma is theorigin of an adenocarcinoma apparent from the morphologyof the nodal metastases. Metastatic adenocarcinomaswith enteric morphology can arise in the sinonasalregion; they are CK 20-positive, like their counterpartsof colonic origin [21]. Thyroglobulin, calcitonin,and TTF-1 are useful markers to probe the thyroid originof a neoplasm of unknown origin [83]. Adenocarcinomaof the prostate may present as metastasis in the leftside of the neck, especially in the supraclavicular nodes.The diagnosis can be confirmed by using the prostatespecificantigen (PSA) test (Table 9.4).The presence of oestrogen receptors and gross cysticdisease fluid protein 15 (GCDFP-15) would suggest abreast origin for adenocarcinoma, but these markers arenon-specific for the breast. Lung adenocarcinomas arepositive for TTF-1 and B 72.3 (Table. 9.4) [83].Benign glandular inclusions in cervical lymph nodesshould not be mistaken for metastatic adenocarcinomas;heterotopic glands of salivary tissue are commonin the paraparotid lymph nodes and less common in theupper cervical nodes. Acinic cell carcinomas, mucoepidermoidcarcinomas, Warthin’s tumour and pleomorphicadenomas have been described in cervical lymphnodes, and they should not be confused with metastaticadenocarcinomas [23, 67, 131].