Sézary Syndrome in West Sweden: Exploring Epidemiology, Clinical Features, and Treatment Patterns in a Registry-Based Retrospective Analysis.

Simple Summary: Sézary syndrome (SS) is a rare and aggressive form of cutaneous T-cell lymphoma. Despite various treatments, it remains incurable, with a median survival of only 2.1 years. This retrospective study of 17 SS patients in West Sweden from 2012 to 2024 aimed to understand demographic characteristics, treatment effectiveness, and disease progression. Only 35% of patients showed the classic symptoms at diagnosis, indicating the need for personalized diagnostic approaches. Different treatment modalities were used, but combination therapy showed advantages in median survival over monotherapies. Notably, triple therapy involving retinoids, interferon alpha, and extracorporeal photopheresis (ECP) exhibited the longest median time to the next treatment, at 14.1 months. However, early initiation of ECP did not improve outcomes. This study underscores the complexity of SS, emphasizes the urgent need for more effective treatments, and highlights the importance of future prospective research in optimizing treatment strategies. Sézary syndrome (SS) is a rare primary cutaneous T-cell lymphoma variant. Despite various treatment options, it remains incurable, with a poor prognosis. There is an urgent need for additional descriptive research to enhance our understanding and treatment of SS. The aim of this retrospective register-based study was to outline patients' demographic characteristics; investigate the clinical, histopathological, and molecular findings; and assess treatment effectiveness with a focus on time to next treatment (TTNT) and disease progression. Data on 17 patients with SS were obtained from the primary cutaneous lymphoma register in West Sweden between 2012 and 2024. The results revealed that not all patients exhibited the classical triad of symptoms at diagnosis, emphasizing the need for personalized diagnostic approaches. The median survival was only 2.1 years, which reflects the aggressive nature of SS. The longest median TTNT was observed in triple therapy involving retinoids, interferon alpha, and extracorporeal photopheresis (ECP). There was no significant difference in TTNT between various lines of treatment. Early initiation of ECP treatment did not result in improved outcomes. This study highlights the importance of combination therapy for improved outcomes and underscores the need for future studies to identify optimal treatment approaches. [ABSTRACT FROM AUTHOR]