Anal verrucous carcinoma is not related to infection with human papillomaviruses and should be distinguished from giant condyloma (Buschke-Löwenstein tumour)

Aims Verrucous carcinoma (VC) is a variant of well differentiated squamous cell carcinoma and is in the anal region regarded as synonymous with giant condyloma (Buschke-Lowenstein tumor) (BLT). Etiology, diagnostic criteria and clinical behavior of both lesions are controversial. Recent studies suggest that VC at other sites is not associated with human papillomaviruses (HPV). We hypothesized that anal VC is also not related to HPV, while BLT is a HPV-induced lesion. Methods and results Ten cases of VC and 4 cases of BLT were included. Several techniques were used for HPV detection: in situ hybridization for HPV6, 11, 16 and 18, six different PCR protocols for detection of at least 89 HPV types from Alpha-, Beta-, Gamma- and Mu-PV genera, and in situ hybridization for high risk HPV E6/E7 mRNA. p16 immunohistochemistry and morphometric analysis were also performed. Alpha-, Gamma- and Mu-PVs were not found in any case of VC, while HPV6 was detected in all cases of BLT. p16 overexpression was not present in any of the lesions. Among microscopic features, only the absence of koilocytosis and enlarged spinous cells seem to be useful to distinguish VC from BLT. Conclusions Our results suggest that anal VC, similarly to VC at other sites, is not associated with HPV infection and must be distinguished from BLT which is associated with low risk HPV. Only with well-set diagnostic criteria will it be possible to ascertain clinical behavior and optimal treatment for both lesions. This article is protected by copyright. All rights reserved.