Characteristics and outcomes of 727 patients with mycosis fungoides and Sézary syndrome from a Brazilian cohort.

Background: Mycosis fungoides (MF) and Sézary syndrome (SS) are the most prevalent cutaneous lymphomas. They were not described in a large Brazilian cohort yet. We aimed, with this single-center, retrospective cohort analysis, to describe the characteristics and outcomes of MF/SS in a tertiary public health service in Brazil.

Methods: MF/SS patients evaluated at the University of São Paulo Medical School between 1989 and 2018 were included. Data were collected at diagnosis. Demographic, clinical, histopathological, immunopathological, molecular, laboratory, and follow-up data were analyzed.

Results: Among 727 patients, 92.6% (673) were diagnosed with MF, 7.4% (54) with SS. There were 51.2% (372) of males, 48.8% (355) of females. The median age was 51.8 years; it was higher in erythrodermic MF (60.2) and SS (60.9). Among MF, 41.8% (281) had classic MF, 4.9% (33) folliculotropic MF, 1.8% (12) granulomatous slack skin, and 0.3% (2) pagetoid reticulosis. Common subtypes included erythrodermic (14.1%, 95), hypopigmented (10.8%, 73), and poikilodermatous MF (10.8%, 73). Extracutaneous involvement was rare. Five, 10, 20, and 30-year overall survival rates were 97.3%, 92.4%, 82.6%, and 82.6% for early-stage, and 58.6%, 42.7%, 20.8%, and 15.4% for advanced-stage disease, respectively. After multivariate analysis, SS diagnosis, folliculotropic MF, erythrodermic MF, clinical stage, age (≥60 years), increased lactate dehydrogenase, and large cell transformation conferred poorer prognosis.

Conclusions: We observed a higher percentage of hypopigmented MF compared to the literature, and demographic (older age) and prognostic (poorer prognosis) similarities between erythrodermic MF and SS, suggesting a possible relationship between these erythrodermic lymphomas. Factors associated with a poorer prognosis were compatible with the literature.