Lichen sclerosus is frequently present in penile squamous cell carcinomas but is not always associated with oncogenic human papillomavirus

BACKGROUND: Penile squamous cell carcinoma (SCC) may occur on pre-existing lesions of lichen sclerosus (LS). However, the prevalence of histological changes of LS in penile SCC is not well established. Moreover, mucosal oncogenic human papillomaviruses (HPVs) are sometimes detected in penile SCC, but have not been systematically sought in LS-associated penile SCC. OBJECTIVES: To establish the prevalence of LS histological changes and of mucosal oncogenic HPV in a series of patients with penile SCC. METHODS: Consecutive cases of histologically proven penile SCC from a single university hospital over a 14-year period were retrospectively selected and reviewed. Histological signs of LS were systematically sought. HPV was detected by polymerase chain reaction (PCR) amplification of DNA from paraffin-embedded skin samples using general primers GP5+/GP6+ (allowing detection of mucosal HPV) and oncogenic type 16-, 18-, 31- and 33-specific primers. RESULTS: Eighteen cases of penile SCC were found. The mean +/- SD age of patients at diagnosis was 67.3 (14.5 years). In eight of 18 (44%) cases, SCC was associated with histological features of LS. Seventeen skin biopsy specimens of SCC (nine without and eight with LS histology) were subjected to PCR amplification for HPV. Mucosal HPV was detected in six of them (35%). Five of nine SCCs without histological features of LS were positive for mucosal HPV: three with HPV type 16 and two with only general primers. In contrast, all eight SCCs associated with LS were negative for oncogenic HPV types, although one was positive with general primers. CONCLUSIONS: Penile SCC seems to be frequently associated with LS histological changes. As with vulval SCC, we found that non-LS-associated penile SCC tended to be frequently associated with oncogenic HPV infection, whereas LS-associated penile SCC was not. Larger series are needed to confirm this association.