The great mimic: A six-year retrospective study on mycosis fungoides and the use of histologic criteria to define adequacy of treatment

ABSTRACT

BACKGROUND: Mycosis fungoides (MF) is the most common cutaneous T-cell lymphoma. Diagnosis relies on clinicopathological correlation. OBJECTIVE: To describe the clinicodemographic characteristics of patients with MF and to identify histologic criteria that will signify adequate treatment. METHODS: Registries from years 2004 to 2009 were searched for biopsy-proven MF. Charts were retrieved and clinicodemographic data gathered. Pre- and post-treatment biopsy slides were reviewed by a dermatopathologist blinded to the patients's treatment status. Pre-selected histologic criteria were evaluated for each slide. Pearson's chi-square and Fisher's exact test were used to analyze for statistical significance of each criteria. RESULTS: There were 34 biopsy-proven MF from years 2004 to 2009. Male-to-female ratio was 1:1.8. Mean age at initial diagnosis was 46.7 years (13-81). Among the 16 patients with fully retrievable records, the most common presentation was that of hypopigmented patches. Age ? 60 years seemed to have significant association with relapse (P=0.02). Epidermotropism of ? 5 (P=0.03), absent to focal lymphocyte tagging (P=0.04), and dropping of haloed lymphocytes from >10 to ? 10 (P=0.01) somehow differentiated treated from untreated MF. CONCLUSIONS: The hypopigmented variant of MF may be more common in Asian countries. Age ? 60 years old may be associated with higher risk of relapse. Grading epidermotropism, lymphocyte tagging and haloed lymphocytes may be helpful in determining adequacy of treatment of MF. However, given the small sample size of the present study, future larger studies are needed to confirm these findings.