Pathology of the Head and Neck

Nasopharynx and Waldeyer’s Ring Chapter 6 189lymph node or carcinoma arising in a branchiogeniccyst is probably a hypothetical entity. Reports of a supposedbranchiogenic carcinoma included an extremelywell-differentiated SCC arising in the backgroundof longstanding chronic inflammation and scarring,one carcinoma arising from pre-auricular ectodermalremnants of the first pharyngeal/branchial cleft andanother report of a well-differentiated mucoepidermoidbranchiogenic carcinoma [16, 154, 178]. Treatmentof SCC of Waldeyer’s ring is surgical resectionwith a neck dissection.6.3.6 Malignant Lymphomasof Waldeyer’s ringabFig. 6.8. Tonsillar carcinoma. a Tonsillar squamous cell carcinomasfrequently arise from the crypt epithelium. The carcinoma infiltratesdeeply into the surrounding structures including skeletalmuscles. b Cystic lymph node metastasis showing complex papillationswhich are lined by squamous epithelium; the cyst contentis necrotic debrissillectomies. This practice has provided overwhelmingevidence that isolated carcinomas in neck lymphnodes are metastases and not so-called primary“branchiogenic carcinomas” within a cervical lymphnode. The evolution of in situ or invasive SCC fromnon-neoplastic squamous epithelium through dysplasiais viewed as the most important criterion for thehistopathological diagnosis of a primary branchiogeniccarcinoma. Primary cystic carcinoma arising in aThis section gives a brief overview of lymphomas ofWaldeyer’s ring. For a more detailed description, includinggenetic characteristics of these lymphomassee the WHO classification and the revised European-American classification of lymphoid neoplasms [74,95]. Extranodal lymphomas of Waldeyer’s ring constituteabout 5–10% of all lymphomas in the USA andEurope, about 15% in Hong Kong and about 10–20%in Japan. Of all lymphomas involving Waldeyer’s ring,80% are primary to this site and the tonsillar fossa isthe most common location, followed by the nasopharynxand the base of the tongue. Up to 20% of patientswith tonsillar lymphoma have an associated gastrointestinalinvolvement. Clinical presentation is that ofa localised neoplasm, sore throat, dysphagias, and incases of nasopharyngeal involvement cranial nerve,auditory and nasal symptoms. Between 85 and 90% ofall non-Hodgkin’s lymphomas in Waldeyer’s ring areof the B-cell phenotype, the remainder are of the T-celltype, but regional differences have been reported [146,150]. The vast majority of Waldeyer’s ring lymphomasare high-grade lymphomas, with only less than 15%being of low grade [113]. The majority of AIDS-relatedextranodal head and neck lymphomas are aggressiveB-cell lymphomas of the Burkitt type or immunoblasticdiffuse large B-cell lymphomas [207].6.3.6.1 Mantle Cell LymphomaICD-O:9673/3Mantle cell lymphoma (or centrocytic (mantle cell) lymphomain the Kiel classification; diffuse, small cleavedcell type in the Working Formulation) constitutes about5% of all non-Hodgkin’s B-cell lymphomas. Commonextranodal sites are the spleen, bone marrow, gastrointestinaltract and Waldeyer’s ring, particularly the palatinetonsil.