DNA analysis indicates patient-specific human papillomavirus type 16 strains in Bowen's disease on fingers and in archival samples from genital dysplasia

Human papillomavirus (HPV) type 16 is causally involved in the pathogenesis of anogenital cancer and has also been demonstrated in some patients with Bowen's disease (BD) on the fingers. From two women with HPV 16 in BD on the fingers, and in archival samples from genital dysplasia, collected as long as 26 years ago, the non-coding region of the virus was amplified by the polymerase chain reaction and sequenced. The HPV 16 DNA sequences found in the finger lesions and in the genital archival samples showed no diversities within single patients. Compared with an HPV 16R reference sequence, one patient showed a unique T nucleotide at position 78, whereas the other patient exhibited T and A nucleotides at positions 7193 and 7521, respectively. In one of the patients, the same strain of HPV 16 was found in a digital tumour 26 years after its clearance from the genital tract. DNA sequence analysis indicated patient-specific HPV 16 strains. Auto-inoculation from the genital tract was favoured as a plausible explanation of why HPV 16 caused BD on the fingers.