Japanese Dermatological Association Guidelines: Clinical Questions of Guidelines for Extramammary Paget Disease 2025

Extramammary Paget disease (EMPD) is a rare malignancy that primarily arises in apocrine gland-bearing areas such as the genital, perianal, and axillary regions. The clinical and biological heterogeneity of EMPD, together with a lack of evidence from large-scale studies, has made it difficult to establish standardized approaches to diagnosis and treatment. To address these issues, the 2025 Japanese Guidelines for the Management of EMPD were developed, providing evidence-based recommendations tailored to the healthcare context in Japan. These guidelines were constructed using the Minds Guideline Development Manual 2020 (ver. 3.0), adhering to systematic review principles and incorporating both Japan and international research findings. A multidisciplinary panel of dermatologists, oncologists, surgeons, and other specialists developed the guidelines through a consensus-based process, which included structured discussions and grading of evidence. The primary focus of this condensed version is on six critical clinical questions, which address key aspects of EMPD management, including the role of mapping biopsy in diagnosis, the use of sentinel lymph node biopsy in cases of suspected dermal invasion, the efficacy of nonsurgical therapies when surgery is not an option, the efficacy of lymph node dissection for multiple regional lymph node metastases, the efficacy of radiation therapy after regional lymph node dissection, and systemic treatment options for advanced disease. The recommendations aim to improve diagnostic accuracy, optimize therapeutic approaches, and support clinical decision-making by providing a clear framework for the management of EMPD. By focusing on these critical areas, the guidelines strive to enhance patient outcomes and contribute to the advancement of evidence-based care for this rare and challenging malignancy.