title: In situ mantle cell lymphoma in the nasopharynx.
abstract: BACKGROUND
  Mantle cell lymphoma (MCL) is a B-cell neoplasm with an aggressive clinical course. Recently, an indolent type of MCL has been described under the term in situ MCL.
  
  
  RESULTS
  We report a case of a 70-year-old woman who presented with nasal obstruction. A mass, located in the nasopharynx, was found. Histologic examination revealed lymphoid hyperplasia characterized by CD5 and cyclin D1-positive mantle zone cells, findings consistent with in situ MCL. Three years later, a new biopsy was performed, which showed the same histologic and immunohistochemical (IHC) findings to those observed in the first biopsy. The diagnosis of in situ MCL was confirmed by fluorescence in situ hybridization (FISH) analysis for t(11;14). Since then, the patient has remained free of an overt lymphoma.
  
  
  CONCLUSIONS
  In situ MCL may be observed in the nasopharynx, and it would be appropriate to perform cyclin D1 immunostain in cases with marked follicular hyperplasia accompanied by clinical suspicion of lymphoma.
authors.affiliation: Department of Pathology, Medical School, Aristotle University of Thessaloniki, Thessaloniki, Greece.
authors.forename: Triantafyllia
authors.initials: T
authors.lastname: Koletsa
authors.forename: Konstantinos
authors.initials: K
authors.lastname: Markou
authors.forename: Sevasti
authors.initials: S
authors.lastname: Ouzounidou
authors.forename: Fani
authors.initials: F
authors.lastname: Tsiompanou
authors.forename: Georgios
authors.initials: G
authors.lastname: Karkavelas
authors.forename: Ioannis
authors.initials: I
authors.lastname: Kostopoulos
mesh_terms: D000368:Aged; D001707:Biopsy, Needle; D002278:Carcinoma in Situ / Q000175:diagnosis / Q000473:pathology*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D017404:In Situ Hybridization, Fluorescence; D007828:Laryngoscopy / Q000379:methods; D020522:Lymphoma, Mantle-Cell / Q000175:diagnosis / Q000473:pathology*; D015508:Nasal Obstruction / Q000175:diagnosis / Q000209:etiology; D009303:Nasopharyngeal Neoplasms / Q000175:diagnosis / Q000473:pathology*; D009367:Neoplasm Staging; D018570:Risk Assessment; D013997:Time Factors; D014057:Tomography, X-Ray Computed / Q000379:methods; D057832:Watchful Waiting
keywords: Waldeyer's ring; in situ lymphoma; in situ mantle cell lymphoma; mantle cell lymphoma; nasopharynx