P16 Expression in Squamous Cell Carcinomas of the Urinary Bladder Is Not Related to Infection with High Risk Human Papilloma Virus 16 and 18
JR Chapman-Fredricks, M Cioffi-Lavina, C Gomez-Fernandez, P Ganjei-Azar, M Jorda. University of Miami Jackson Memorial Hospital and Sylvester Comprehensive Cancer Center, Miami, FL
Background: p16 INK4a (p16) is a tumor suppressor gene located on chromosome 9p21. The translational product of this gene can be over expressed as a result of infection by high-risk human papillomavirus (HPV). This increased expression can be detected by immunohistochemical analysis and thus p16 has been used as a surrogate marker for the presence of HPV infection in gynecologic malignancies. Over expression of this protein has also been detected in non-gynecologic neoplasms, such as head and neck and bladder carcinomas. A subset of head and neck carcinomas are largely associated with HPV 16 infection. The aim of this study is to determine whether the increased expression of p16 protein in SCC of the urinary bladder is due to the presence of HPV 16 and 18.
Design: We reviewed 14 cases of primary squamous cell carcinoma (SCC) of the urinary bladder (8 arising in males and 6 in females) which in a prior study proved to be positive for p16 (DAKO M7247, clone 484, dilution of 1:50) by immunohistochemical analysis. In situ hybridization for high risk HPV types 16 and 18 was performed in all cases. Two SCCs of the uterine cervix positive for high risk HPV types 16 and 18 by in situ hybridization were used as positive control.
Results: In situ hybridization for the detection of high risk HPV 16 and 18 was negative in all cases.
Conclusions: The over expression of p16 observed in SCC of the urinary bladder is probably not related to the presence of high risk HPV 16 and 18.
Category: Genitourinary (including renal tumors)
Monday, March 22, 2010 9:30 AM
Poster Session I Stowell-Orbison/Surgical Pathology/Autopsy Awards Poster Session # 116, Monday Morning