Introduction The clinical morphology of anogenital warts may vary from flat, filiform, popular or verrucous to giant condyloma acuminata, and Buschke-Löwenstein tumour. Clinically atypical-looking genital warts may alarm the clinician because of their suspected malignant potential, which may cause anxiety, often leading to aggressive interventions. We conducted this study to find out whether clinically atypical-looking anogenital warts are more likely to be premalignant or malignant as compared to typical warts.

Methods Data of forty-one (37 males, 4 females) patients with anogenital warts was retrospectively analysed. After a detailed literature review and in-house discussions, criteria for anogenital warts with typical and atypical clinical morphology were defined. Clinical photographs of the anogenital warts were independently reviewed by three dermatologists, and HPV genotyping results, histological evaluation, and immunohistochemical analysis for p53 expression were evaluated.

Results Fifteen (36.6%) anogenital warts were classified as atypical by at least two out of three blinded dermatologists. The histological examination showed mitotic figures in 29/41 (70.8%), dysplasia in 14/41 (44.1%) specimens and p53 positivity in 34/41 (82.9%) of specimens. There was no significant difference in the high-risk HPV genotyping (p=0.6), frequency of dysplastic changes on histology (p=0.3) and immunohistochemistry with p53 (p=0.07) between clinically typical and atypical-appearing anogenital warts. Similarly, no significant difference was found in the frequency of dysplastic changes (p=0.3) or p53 expressions (p=0.5) based on the HPV genotypes.

Conclusion The atypical clinical morphology of anogenital warts may not be a marker of increased malignant potential. High-risk HPV genotypes do not have a statistically significant association with dysplasia or positive immunohistochemistry with p53.

Support: The part of the study was done with financial support from Department of Biotechnology, Government of India