Etiological Role of Human Papillomavirus Infection in the Development of Penile Cancer.

To examine an association between human papillomavirus (HPV) infection and penile cancer among Japanese patients.

Thirty-four patients with penile cancer were enrolled in this study. DNA was extracted from paraffin-embedded tumor-tissue samples, and HPV-DNA tests and genotyping were performed. In all of samples, in situ hybridization (ISH) was performed to locate HPV-DNA in tumor tissue; expression levels of p16-INK4a, mini-chromosome maintenance protein-7(mcm-7), HPV-L1, and Ki-67 were analyzed using immunohistochemical methods.

HPV and high-risk (HR)-HPV were detected in 14 (41.2%; 95% confidence intervals [CI], 24.6-57.7%) and 12 (35.2%; 95%CI, 19.2-51.4%) cases, respectively. HPV16 was the most frequently detected HPV type. Among the HR-HPV-positive cases, a punctate HR-HPV-DNA signal pattern was detected by ISH in tumor-cell nuclei. P16-INK4a expression was expressed in 66.7% (95%CI, 42.8-90.1%) of HR-HPV positive-cases, and was significantly frequent and stronger in HR-HPV-positive cases than in HPV-negative cases. There were no significant differences in the occurrence and distribution of mcm-7 and Ki-67 expression between HPV-positive and HPV-negative cases. HPV-L1 expression was not observed in any of the examined cases.

HPV infection may have had an etiological role in 41% examined cases of penile cancer in Japan.

International journal of infectious diseases : IJID : official publication of the International Society for Infectious Diseases. 2018 Nov 10 [Epub ahead of print]

Jiro Sakamoto, Kazuyoshi Shigehara, Kazufumi Nakashima, Shohei Kawaguchi, Takao Nakashima, Masayoshi Shimamura, Mitsuru Yasuda, Taku Kato, Toru Hasegawa, Yoshitomo Kobori, Hiroshi Okada, Takashi Deguchi, Kouji Izumi, Yoshifumi Kadono, Atsushi Mizokami

Department of Urology, Kanazawa University Graduate School of Medical Science., Department of Urology, Kanazawa University Graduate School of Medical Science. Electronic address: ., Department of Urology, Ishikawa Prefectural Central Hospital., Department of Urology, Nomi City Hospital., Department of Urology, Gifu University Hospital., Department of Urology, Hasegawa Hospital., Department of Urology, Dokkyo Medical School Koshigaya Hospital.