Japanese Dermatological Association Guidelines: Outlines of Japanese Guidelines for the Management of Primary Cutaneous Lymphomas 2025.

Since the publication of the Japanese guidelines for the management of cutaneous lymphomas in 2020, the WHO classification of hematolymphoid neoplasms has been updated, and a number of novel systemic drugs for cutaneous T-cell lymphoma have been approved in Japan. In 2025, we revised the Japanese guidelines for the management of cutaneous lymphomas in consideration of recent advances in our understanding of the pathophysiology and classification of cutaneous lymphomas, together with the update in treatment strategies reflecting the advent of novel drugs. This revision was also conducted under the Japanese Dermatological Association's commission, incorporating expert reviews and public comments. In addition to a brief explanation of the epidemiology, diagnosis, staging system, prognosis, and management of the different types of cutaneous lymphomas, we herein provide recommendations for 12 clinical questions (CQs) regarding treatment options that may vary even among experts. A systematic review process and the selection of recommendations to individual CQs were conducted in accordance with the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) scheme by a multidisciplinary expert panel consisting of dermatologists, hematologists, and a radiation oncologist. In these guidelines, we present outlines of the revised Japanese guidelines for the management of cutaneous lymphomas.