title: Ciliated HPV-related Carcinoma: A Well-differentiated Form of Head and Neck Carcinoma That Can Be Mistaken for a Benign Cyst.
abstract: Although human papillomavirus (HPV)-related oropharyngeal carcinomas (HPV-OPCs) are generally regarded as "poorly differentiated," they actually maintain a close resemblance to the lymphoepithelium of the tonsillar crypts from which they arise: they are basaloid, exhibit minimal keratinization, and are often permeated by lymphocytes. In rare cases, the presence of cilia in a primary HPV-OPC and their persistence in lymph node metastasis can confound the distinction between a benign and malignant process. Three cases of ciliated HPV-OPCs were identified from the archives of The Johns Hopkins Head and Neck Pathology consultation service. HPV status was determined using p16 immunohistochemistry and high-risk HPV in situ hybridization. All 3 patients presented with a cystic lymph node metastasis without a known primary carcinoma. One metastasis was originally diagnosed as a branchial cleft cyst only to regionally recur 7 years later. In 2 cases, a primary HPV-OPC was found in the tonsil. The carcinomas exhibited both nonkeratinizing squamous epithelium and cystic/microcystic spaces lined by ciliated columnar cells. Both the squamous and ciliated cells were HPV positive. This report draws attention to a novel variant of HPV-related head and neck cancer that exhibits ciliated columnar cells. This variant challenges prevailing notions that: (1) HPV-OPCs are uniformly poorly differentiated cancers; (2) cilia are an infallible feature of benignancy; and (3) presence of cilia is a reliable criterion for establishing branchial cleft origin when dealing with cystic lesions of the lateral neck.
authors.affiliation: Departments of *Pathology †Otolaryngology/Head and Neck Surgery ‡Oncology, The Johns Hopkins Medical Institutions, Baltimore, MD.
authors.forename: Justin A
authors.initials: JA
authors.lastname: Bishop
authors.forename: William H
authors.initials: WH
authors.lastname: Westra
mesh_terms: D000368:Aged; D014408:Biomarkers, Tumor / Q000032:analysis; D001706:Biopsy; D002277:Carcinoma / Q000737:chemistry / Q000556:secondary* / Q000628:therapy / Q000821:virology; D002454:Cell Differentiation; D002923:Cilia / Q000473:pathology; D019941:Cyclin-Dependent Kinase Inhibitor p16 / Q000032:analysis; D003560:Cysts / Q000473:pathology*; D004279:DNA, Viral / Q000235:genetics; D003937:Diagnosis, Differential; D003951:Diagnostic Errors; D005260:Female; D061809:Human Papillomavirus DNA Tests; D006801:Humans; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D009959:Oropharyngeal Neoplasms / Q000737:chemistry / Q000473:pathology* / Q000628:therapy / Q000821:virology; D027383:Papillomaviridae / Q000235:genetics; D030361:Papillomavirus Infections / Q000473:pathology* / Q000628:therapy / Q000821:virology; D011237:Predictive Value of Tests; D012367:RNA, Viral / Q000235:genetics
chemical_list: D014408:Biomarkers, Tumor; D019941:Cyclin-Dependent Kinase Inhibitor p16; D004279:DNA, Viral; D012367:RNA, Viral