Differentiated precursor lesions and low-grade variants of squamous cell carcinomas are frequent findings in foreskins of patients from a region of high penile cancer incidence

Abstract

Aims: About 10-20% of all penile squamous cell carcinomas (SCCs) originate in the foreskin, but knowledge about preputial precursor and associated lesions is scant. The aims of the present study were to determine the prevalence of various precancerous and cancerous lesions exclusively affecting the foreskin, and to describe their pathological features.

Methods and results: One hundred consecutive circumcision specimens from symptomatic patients living in a region of high penile cancer incidence were analysed. Clinical diagnoses included mostly phimosis and chronic balanoposthitis (40 and 35 cases, respectively), but also a tumour mass (11 cases). Histopathological lesions found included: squamous hyperplasia in 61 cases; lichen sclerosus in 53 cases; penile intraepithelial neoplasia (PeIN) in 30 cases (all differentiated PeIN, with two cases showing multicentric foci of basaloid and warty-basaloid PeIN); and invasive SCC in 11 cases (three usual, three pseudohyperplastic, two verrucous-pseudohyperplastic, and one case each of basaloid, papillary and mixed usual-basaloid carcinomas). Lichen sclerosus was present in all low-grade SCC cases. Patients with no lesions were younger (mean age 44 years) than those with precursor lesions (mean age 54 years) or with invasive SCC (mean age 68 years). Immunohistochemistry for p16(INK4a) was performed in 19 precancerous lesions. All differentiated PeINs (18 lesions) were negative, and one basaloid PeIN was positive.

Conclusions: The frequent coexistence of lichen sclerosus, squamous hyperplasia, differentiated PeIN and low-grade SCC suggests a common non-human papillomavirus related pathogenic pathway for preputial lesions, and highlights the importance of circumcision in symptomatic patients for the prevention of penile cancer.