Prevalence of human papillomavirus DNA in cutaneous neoplasms from renal allograft recipients supports a possible viral role in tumour promotion

It is well established that renal allograft recipients (RARs) have an increased incidence of viral warts and premalignant and malignant cutaneous lesions, and the risk of their development increases in proportion to duration of graft survival. It has been postulated that, in addition to the effects of prolonged immunosuppression and previous sun exposure, human papillomaviruses (HPV) may also contribute to the carcinogenic process. In this study, the prevalence of HPV DNA was examined in a range of premalignant and malignant cutaneous tumours from 50 immunosuppressed patients (47 renal allograft recipients plus three cardiac allograft recipients) and 56 immunocompetent patients using Southern hybridisation as a low-stringency screening method and type-specific polymerase chain reaction (PCR) assays for eight HPV types. The combined results for renal allograft recipients show that HPV DNA was detectable in 79% of viral warts, 42% of premalignant keratoses, 33% of intraepidermal carcinomas, 43% of invasive squamous cell carcinomas and 16% of uninvolved skin specimens (squamous cell carcinomas/renal allograft recipients significantly different at P