The occurrence and clinical characteristics of cutaneous squamous cell carcinoma (cSCC) associated with cosmetic skin bleaching have been well documented in the literature. However, the histopathological characteristics have not yet been reported. This study aimed to describe the histological abnormalities observed in cases of cSCC associated with cosmetic skin bleaching and to explore the potential contributing factors.

We re-analysed archived paraffin-embedded tissue blocks from all cases of cSCC diagnosed in different pathology laboratories in Dakar between November 2006 and October 2021.

We collected 19 cases of cSCC, all occurring in women, with a mean age of 58 years. On average, the women had been practising cosmetic skin bleaching for 20 years. Most of them (14 cases) used bleaching products containing a mixture of hydroquinone and clobetasol propionate. All carcinomas were well-differentiated, and 17 cases (89.5%) were invasive. Histological abnormalities associated with the cSCC included intense fibrosis with a lymphoplasmacytic infiltrate in all cases, telangiectasias in 18 cases (94.7%), exogenous ochronosis deposits in 9 cases (47.4%), and solar elastosis in one case. In addition, koilocytes, histological markers of human papillomavirus (HPV) infection, were identified in 10 cases (52.6%).

cSCC associated with cosmetic skin bleaching exhibit a distinctive histopathological pattern with frequent koilocytosis (52.6%). These findings support a multifactorial pathogenesis in which HPV may act as a cofactor. Future studies using PCR and in situ hybridisation are needed to clarify this potential association.