Genital seborrheic keratoses are human papillomavirus-related lesions. A linear array genotyping test study.

Controversy exists about the meaning of human papillomavirus (HPV) detection in seborrheic keratosis (SK). To clarify the pathogenic contributing role of HPV in the development of genital SK, we have studied 40 genital SKs, 20 extragenital SKs, and 20 non-SK genital lesions by polymerase chain reaction for HPV, using a Linear Array Genotyping test that detects 37 genital HPV types. Twenty-eight of the 40 genital SK specimens (70%) were positive for HPV. Twenty-seven of the 28 positive cases (96%) contained HPV6, one of them associated to HPV18 and HPV35 (4%), and the remaining lesion (4%) harbored HPV55. However, HPV was detected in only 2/20 extragenital SK samples (10%) and in 1/20 non-SK genital lesions (5%). Our results support a pathogenic relationship between HPV and genital SK by showing: 1) a high rate of virus detection in these lesions, with a strong predilection for HPV6, and 2) scarcity of genital HPV types in most of the remaining non-SK cutaneous genital lesions and in the extragenital SKs. HPV cannot be found in a minority of genital SKs using highly sensitive techniques, and therefore, other presently unknown factors may also be implied in the pathogenesis of these lesions.