Epidemiology and prognostic factors for mycosis fungoides and Sézary syndrome in a multi-ethnic Asian cohort: a 12-year review.

BACKGROUND: Limited information exists regarding survival of Asian patients with mycosis fungoides (MF) and Sézary syndrome (SS). OBJECTIVE: To evaluate the epidemiology, outcome and prognostic factors of these patients. METHODS: A retrospective review of MF/SS cases diagnosed from 2000 to 2011 at a tertiary referral dermatology centre in Singapore was performed. RESULTS: Of 246 patients, 63% were male and the median age at diagnosis was 49 years. 73.2% were Chinese, 12.6% Indian, 6.9% Malay and 7.3% Caucasian. A total of 239 patients (97.2%) had MF and seven had SS. Median follow-up duration was 6.3 years, and median duration of symptoms at diagnosis was 13 months. For patients with MF, the majority had early disease (92.8% stage IA-IIA). 3.8% were stage IIB, 1.7% stage III and 1.7% stage IV. Complete response to treatment occurred in 78.2%, partial response in 9.6%, persistent but non-progressive disease in 10.0% and disease progression in 4.1% of patients. Large cell transformation occurred in 4.1% of patients. Mean overall survival during this study was 12.7 years, with death occurring in 2.5% of patients (all ≥stage IIB at diagnosis). For patients with SS, 71.4% presented with stage IVA disease, 28.6% stage IVB. Complete response to treatment occurred in 14.2%, persistent but non-progressive disease in 28.6% and disease progression in 57.2% of patients. Mean overall survival was 3.3 years within this study, with death occurring in 42.9% of SS patients. Prognostic factors associated with favourable recurrence-free survival were male gender (P = 0.008), early disease stage (T1) at diagnosis (P < 0.001) and absence of maintenance treatment after remission (P = 0.01). CONCLUSION: Compared to Caucasian and East Asian cohorts, MF in South-East Asians was diagnosed at a younger age and associated with lower mortality, largely due to greater prevalence of hypopigmented MF.