Evaluation of the role of genital human papillomavirus in the pathogenesisof ungual squamous cell carcinoma

Human papillomaviruses (HPV), and particulary HPV 16, have been associated with ungual squamous cell carcinoma (USCC). But their role in tumor develop ment remains unclear. In genital carcinoma, where the oncogenic role of HPV is well established, integration of HPV DNA into the host cell genome seem s to be important for malignant transformation. To clarify the issue, we ha ve studied the physical state of HPV 16 in 3 cases of in situ USCC by the p olymerase chain reaction and by in situ hybridization. HPV DNA was integrat ed into the human genome in 2 cases and episomal in 1 case. This particular physical state of HPV 16 in USCC, similar to those encountered in anogenit al SCC, confirms the probable role of this kind of virus in the pathogenesi s of USCC.