Clinicopathological Features and Survival Prognosis of Subcutaneous Panniculitis-Like T-Cell Lymphoma: A Population-Based Study from the SEER Database with Supplementary Single-Center Case Validation.

BACKGROUND: Subcutaneous panniculitis-like T cell lymphoma (SPTCL) is a rare entity which primarily involved skin and subcutaneous tissue, with clinicopathological features similar to subcutaneous panniculitis. The etiology, clinical features, clinical outcomes and prognostic factors remain largely unknown.

METHODS: To gain insight into this distinct entity, we summarized the clinicopathologic features of 8 unpublished SPTCL cases and performed a comprehensive analysis based on SEER (Surveillance, Epidemiology, and End Results) database.

RESULTS: Clinically, subcutaneous nodules with no tenderness appeared firstly in seven patients, and cough in one patient. Hemophagocytic syndrome developed in 3 patients. The median progression-free survival (PFS) for the whole cohort was 43 months, while the median overall survival (OS) has not reached. We identified a cohort of 210 SPTCL patients between 2000 and 2020 based on SEER database. Over half of patients had B symptoms (56.2%) and present at advanced stage (55.6%). The 5-year overall survival (OS) rate was 77.6% for the whole cohort. Multivariate analysis showed that age >60 years and diagnosis before the year 2008 were important prognostic factors of OS for SPTCL.

CONCLUSION: Our results identified the clinical characteristics, OS and prognostic factors of a large cohort of SPTCL.