Abstract:

Objective To assess the relationship between human papillomavirus （HPV） and extragenital Bowen′s disease. Methods Regular PCR with consensus primers for L1 region as well as mix primers and nested PCR were performed to detect the DNA of a broad range of cutaneous and mucosal HPV types in tissue samples from lesions of 41 patients with extragenital Bowen′s disease and from normal skin of 48 human controls. Semiquantitative PCR and tyramide-based in situ hybridization （ISH） were also conducted to determine the load and localization of HPV DNA in HPV-positive samples. Results HPV DNA was detected in lesions from 5 （12%） of the 41 patients with extragenital Bowen′s disease. Of the 5 HPV-positive patients, 3 carried mucosal HPV types （HPV16 in 2 cases, HPV 33 in 1 case） with a viral load of 101 to 103 copies, 2 cutaneous HPV types （HPV27 in 1 case and HPV76 in 1 case）. As ISH showed, there was a generalized expression of mucosal HPV DNA in most tumor cell nuclei but not in peritumoral normal tissue, and no expression of cutaneous HPV DNA was observed in lesions. HPV DNA was detected in 1 （2.1%） control tissue sample, which proved to be epidermodysplasia verruciformis-associated HPV23. There was no significant difference in the detection rate of HPV DNA between the patients and controls. The viral load of cutaneous HPV types amounted to 10-2 to 10-3 copies in the 2 patients, which was similar to that of HPV 23 in the normal control. Conclusion Mucosal HPV types may be closely associated with the development of extragenital Bowen′s disease.

Key words: Human papillomavirus, extragenital Bowen's disease, in-situ hybridization, Virus amount