Abstract
Porokeratosis (PK), characterized by keratotic lesions with an atrophic center and a prominent peripheral ridge, with a typical histological hallmark, namely, the cornoid lamella, has two forms: disseminated and localized. While PK often converts into squamous cell carcinoma (SCC), conversion from disseminated superficial porokeratosis (DSP) alone is rarely reported except for one case in which DSP and LP coexisted and converted to SCC. Here, we report the case of a patient with SCC converted from DSP alone, presenting with coin-sized macules on the bottom right of his waist that developed into an ulcer at the center. The patient underwent radiation therapy, which effectively treated the SCC but did not resolve the PK. This article highlights regular follow-up and undergo comprehensive diagnosis, both of which are beneficial to enable early detection and management of DSP that has converted to into SCC; in addition, standardized medical treatment may help improve the treatment therapeutic effect of in similar diseases.