Abstract
IMPORTANCE: Mycosis fungoides and Sézary syndrome (MF/SS) has an increased incidence in Black patients, but clinical characteristics, treatments, and outcomes have been poorly characterized. OBJECTIVE: To assess racial differences in presentation and outcome and identify drivers for racial disparities in MF/SS. DESIGN, SETTING, AND PARTICIPANTS: A retrospective cohort analysis was conducted of 566 patients with MF/SS diagnosed from 1990 to 2020 and seen at the Winship Cancer Institute of Emory University and Grady Memorial Hospital, both in Atlanta, Georgia. Self-reported race and ethnicity were obtained from patient medical records and analyzed as 2 groups: non-Hispanic Black (Black) and all other races and ethnicities, including Asian, Hispanic, White, and unknown/undeclared (non-Black). MAIN OUTCOMES AND MEASURES: Univariate and multivariable models and Kaplan-Meier assessments were analyzed for overall survival and time to next treatment. The primary outcome was to assess differences in overall survival by racial and ethnic group. The hypotheses were formulated prior to data collection. RESULTS: Of the 566 patients with MF/SS identified (mean [SD] age 55 [16.4] years; 270 (47.7%) female), 257 were Black and 309 were non-Black. Black race was associated with increased rates of progression to a higher TNMB stage (39.8% in Black patients vs 29.1% in non-Black patients; P < .001) but not survival. Black patients were younger and had increased female predominance, higher TNMB stage, higher tumor stage, nodal involvement, and higher lactate dehydrogenase level compared with non-Black patients with MF/SS. Hypopigmented MF (HMF) was found in 62 patients, who were mostly Black (n = 59). Hypopigmented MF was significantly associated with survival on univariate and multivariable models, with 10-year survival of 100% in patients with HMF compared with 51.8% in patients without HMF. Black race was only associated with inferior outcomes after excluding patients with HMF who were younger than 60 years (hazard ratio [HR], 1.61; 95% CI, 1.02-2.55; P = .04), but not in patients older than 60 years (HR, 1.20; 95% CI, 0.80-1.81; P = .37). On multivariate analysis, among the cohort without HMF who were younger than 60 years, Black race remained statistically significant when controlling for cancer stage and large-cell transformation (HR, 1.27; 95% CI, 1.08-2.87; P = .43). CONCLUSIONS AND RELEVANCE: In this cohort study, Black patients with MF/SS showed distinct clinical presentations and patterns of progression with heterogeneous outcomes depending on age at presentation and presence of HMF.