title: Primary Squamous Cell Carcinoma of the Upper Genital Tract: Utility of p16(INK4a) Expression and HPV DNA Status in its Differential Diagnosis from Extended Cervical Squamous Cell Carcinoma.
abstract: BACKGROUND
  Primary squamous cell carcinoma (SCC) of the upper genital tract, including the endometrium, fallopian tubes, and ovaries, is extremely rare. It must be distinguished from the mucosal extension of primary cervical SCC because determination of the primary tumor site is important for tumor staging. However, patients with SCC of the fallopian tubes or ovarian surface have often undergone prior hysterectomy with inadequate examination of the cervix, making it difficult to determine the primary site.
  
  
  METHODS
  We compared histologic findings, p16(INK4a) expression, and human papillomavirus (HPV) DNA status in four patients with primary SCC of the upper genital tract and five patients with primary cervical SCC extending to the mucosa of the upper genital tract.
  
  
  RESULTS
  All five SCCs of cervical origin showed strong expression of p16(INK4a), whereas all four SCCs of the upper genital tract were negative, although one showed weak focal staining. Three of the five cervical SCCs were positive for HPV16 DNA, whereas all four primary SCCs of the upper genital tract were negative for HPV DNA.
  
  
  CONCLUSIONS
  Although a thorough histological examination is important, immunonegativity for p16(INK4a) and negative for HPV DNA may be useful adjuncts in determining primary SCCs of the upper genital tract.
authors.affiliation: Department of Pathology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea.
authors.forename: Su Hyun
authors.initials: SH
authors.lastname: Yoo
authors.affiliation: Department of Pathology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Eun-Mi
authors.initials: EM
authors.lastname: Son
authors.affiliation: Department of Pathology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Chang Okh
authors.initials: CO
authors.lastname: Sung
authors.affiliation: Department of Pathology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Kyu-Rae
authors.initials: KR
authors.lastname: Kim
keywords: Carcinoma, squamous cell; DNA probes, HPV; Genes, p16