Topical Combination of Fluorouracil and Calcipotriene as a Palliative Therapy for Refractory Extramammary Paget Disease

Importance: Extramammary Paget disease (EMPD), a rare intraepithelial adenocarcinoma, poses a therapeutic challenge with high postoperative recurrence rates and a limited number of effective local treatment options. Objective: To describe the use and efficacy of a topical combination of fluorouracil and calcipotriene as a palliative therapy for refractory EMPD. Design, Setting, and Participants: This retrospective case series of 3 women with recurrent, refractory EMPD was conducted at Beth Israel Deaconess Medical Center, Boston, Massachusetts and Washington University School of Medicine, St Louis, Missouri. All patients were treated with a 1:1 mixture of fluorouracil, 5%, cream and calcipotriene, 0.005%, cream or ointment. Main Outcomes and Measures: Clinical and histopathological findings. Results: All 3 women (1 in her 50s, 2 in their 70s) presented with recurrent EMPD (vulvar, perianal, and perioral) after surgery and/or irradiation, and their EMPD was refractory to treatment with imiquimod, 5%, cream. Owing to disease progression and/or intolerable adverse effects from imiquimod, the patients began treatment with a 1:1 mixture of fluorouracil, 5%, cream and calcipotriene, 0.005%, cream. This treatment, which was well tolerated, was followed by clinical improvement in symptoms and appearance of the lesions in all 3 cases and histopathological signs of decreased tumor burden in 2 cases. Patients applied the combination topical therapy to affected areas with differing frequencies, ranging from 1 to 2 days per month to 4 consecutive days every 2 weeks. Conclusions and Relevance: Extramammary Paget disease frequently recurs even after aggressive surgical management and can be refractory to many topical and locoregional therapies. Palliative treatment with a combination of fluorouracil and calcipotriene may be a viable option for patients with recurrent, refractory EMPD.