Clinical characteristics, risk factors and long-term outcome of 114 patients with folliculotropic mycosis fungoides

Folliculotropic mycosis fungoides (FMF) is a distinct variant of mycosis fungoides (MF) where atypical T-cells invade the hair follicles. The objective was to assess the clinical features, risk factors for progression, long-term outcome and response to treatment modalities in a large cohort of FMF patients. We, therefore, conducted a single-center retrospective study, reviewing 114 patients with FMF seen from 1987 to 2015 at the cutaneous T-cell lymphoma clinic of the MD Anderson Cancer Center. The mean age at diagnosis of FMF was 57.1 ± 13.5 years. The male to female ratio was 1.2:1. MF stage IA (n = 50, 43.9%) was the most common diagnosed stage, followed equally by stages IB and IIB (n = 23, 20.2%, respectively). Eighty-six patients (75.4%) suffered from pruritus. Concomitant hair loss was observed in 37 (32.5%) subjects. The median number of different treatment modalities used per patient was 4 (range 1–12). Low-dose radiation was beneficial in clearing therapy refractory lesions. The overall survival was influenced by several factors, including advanced age (>65), late stages and the presence of large cell transformation (LCT). Thirty-three of 113 patients (29.2%) progressed to more advanced stages and 26 (23.0%) died, with the cause of death being MF in 11 (9.7%) subjects. In conclusion, patients with FMF have a worse overall 10-year survival rate compared with other MF variants. Several factors, including stage, advanced age and the presence of LCT impact survival. Multiple different treatment approaches may be needed to achieve a good clinical response and to prevent disease progression.