Supplementary Material for: Grenz Ray Therapy for Porokeratosis Ptychotropica: A Case Report

Porokeratosis ptychotropica (PP) is a rare form of porokeratosis that poses significant diagnostic and therapeutic challenges. Given the rarity of PP, there is a paucity of evidence about effective treatment options. We present the first case of porokeratosis ptychotropica being managed with Grenz therapy (a type of superficial, low radiation radiotherapy). Our patient was a 56-year-old female with porokeratosis ptychotropica in the intergluteal cleft and on her right posterior thigh. She was previously unsuccessfully treated with topical, intralesional and oral corticosteroids, topical vitamin D analogues, topical simvastatin-cholesterol cream, topical fluorouracil cream, acitretin, and CO2 laser assisted photodynamic therapy (PDT). She underwent Grenz therapy for 6 sessions, a total dose of 18Gy to all affected areas, with excellent clinical response. After two months of remission, her porokeratosis showed early signs of recurrence. This is the first reported case of porokeratosis ptychotropica being treated with Grenz rays. With no effective treatment, Grenz therapy may present a potential effective treatment for some patients.