Overall and Cause-Specific Mortality Among Patients With Cutaneous T-Cell Lymphoma in the United States.

Introduction: Little is known about long-term outcomes and causes of death for individuals with cutaneous T-cell lymphoma. Methods: We used SEER-18 registry data to examine outcomes among 9886 adults with mycosis fungoides (MF), Sézary syndrome (SS), primary cutaneous anaplastic large cell lymphoma (pcALCL), and subcutaneous panniculitis-like T-cell lymphoma (SPTCL) diagnosed from 2000 to 2018. We calculated overall survival (Kaplan-Meier method), standardized mortality ratios (SMRs), absolute excess risk (AER) of death, and cumulative incidence of cause-specific mortality. Results: Individuals with CTCL were at increased risk of all-cause mortality relative to age-matched controls, with SMR ranging from 1.57 (95% CI: 1.49-1.65) in MF to 5.61 (95% CI: 4.65-6.7) in SS. This was true even for those who initially presented with early-stage disease. After a median follow-up of 64 months, the cumulative incidence of lymphoma-related death was 16.5%, compared to 10.5% other causes, 9.6% cardiovascular, 9.1% second primary malignancy, 1.8% infection, and 1.1% unknown cause. People diagnosed with CTCL were at higher risk of mortality due to leukemia and infectious causes than control populations, but secondary causes made overall minor contributions to total mortality. Conclusion: This population-level analysis revealed that individuals with CTCL were at increased risk of all-cause mortality relative to age-matched controls and that lymphoma remained a significant cause of death even in those presenting with early-stage disease. Trial Registration: The authors have confirmed clinical trial registration is not needed for this submission.