Split Course Superficial Radiotherapy in Scrotal Extramammary Paget’s Disease Allows Course Completion With Minimal Side Effects: A Case Study

Abstract

Symptomatic anogenital extramammary Paget’s disease (EMPD) is a disease of the elderly that can be difficult to eradicate with topical therapies. Surgery with the recommended margins is effective, but the tissue loss may impact quality of life. Fractionated radiotherapy (RT) is recommended to 60 Gy at least, but continuous treatment may result in significant local acute effects making completion difficult. A fit, immune competent, 80-year old male of Chinese heritage was treated with definitive RT with curative intent for symptomatic recurrent multifocal EMPD of the scrotum and base of penis. Superficial RT was prescribed using a split course approach on an Xstrahl® 300 machine with a generating energy of 100kV, HVL = 3.95 mm Al, delivered with 30 cm focus to source distance. Phase 1 was 20 Gy in 10 daily fractions at five per week given Monday to Friday. At least two weeks later, phase 2 was given using the same schedule. After another two weeks or more after completion of phase 2, an identical third phase of 20 Gy in 10 fractions, with no change in field size between the phases, was administered. The breaks between phases allowed for skin recovery. The highest toxicity was dry desquamation at the end of phase 1. The skin returned to normal four weeks after the final phase. The patient remained fully potent during and after therapy. With a planned split course approach, the full course to 60 Gy was completed according to schedule with minimal symptoms or impact on daily life.