Survival of Subcutaneous Panniculitis-Like T-Cell Lymphoma and Peripheral T-Cell Lymphoma Not Otherwise Specified: A Propensity-Matched Analysis of the Surveillance, Epidemiology, and End Results Database

Subcutaneous panniculitis-like T-cell lymphoma (SPTCL) is a rare subtype of peripheral T-cell lymphoma (PTCL) with limited studies. We used the Surveillance, Epidemiology, and End Results 18 registry to identify a cohort of unselected patients with SPTCL and compared its outcomes with patients with PTCL not otherwise specified (NOS), the most common subtype among all PTCL. The overall survival of SPTCL was much better than PTCL NOS even after matching for potential confounders including age at diagnosis, year of diagnosis, sex, marital status, and race. Background Subcutaneous panniculitis-like T-cell lymphoma (SPTCL) is a rare entity with no previous population-based study. Materials and Methods We used the Surveillance, Epidemiology, and End Results 18 database to identify adult patients with SPTCL and peripheral T-cell lymphoma not otherwise specified (PTCL NOS) diagnosed between 1973 and 2011. The actuarial survival of SPTCL was compared with a propensity-matched cohort of PTCL NOS. Multivariate analysis was conducted using weighted Cox proportional hazard regression model. Results Patients with SPTCL (n = 118), compared with PTCL NOS (n = 3296), were more likely to be younger (median age of 47 vs. 62 years; P < .01), women (67% vs. 40%, P < .01), and diagnosed with stage I/II disease (46% vs. 36%; P = .01). The 5-year actuarial, relative, and cause-specific survival for SPTCL was 40%, 57%, and 64%, respectively. After propensity-matching, the 5-year overall survival (OS) of SPTCL was better than that of PTCL NOS (57% vs. 40%; P < .01). In a multivariate analysis, mortality was significantly lower among SPTCL versus PTCL NOS (hazard ratio, 0.54; 95% confidence interval, 0.39-0.75; P < .01). Among patients with SPTCL, advanced age (P < .01) and diagnosis before the year 2008 (P = .02) were predictors of worse OS. Conclusion Our study provides characteristics and OS of a large cohort of SPTCL. Compared with PTCL NOS, SPTCL patients were more likely to be younger, female, and diagnosed at an early stage. The OS of SPTCL was better than PTCL NOS.