RESUMO
Background and Objectives: Mycosis fungoides (MF) is the most common type of cutaneous lymphoma accompanied by neoplastic T cells. Histopathological changes after phototherapy could be an effective index for evaluation of treatment. The aim of this study was to compare histomorphological changes in Iranian MF patients before and after phototherapy. Methods: Skin biopsies of 20 diagnosed MF patients in Razi dermatology Hospital of Tehran University of Medical Sciences were evaluated based on major and minor diagnostic criteria using Guitart classification to assess histological features of phototherapy. Result: Of 20 studied patients eight patients were man and 12 were woman. Following phototherapy, major histologic criteria including density of infiltrate, epidermotropism and lymphocytic atypia along with some minor histologic criteria such as lymphocytic infiltrate and intraepidermal atypical lymphocytes were significantly alleviated after treatment (p < 0.05). Conclusion: We find a significant decrease in some important histologic parameter of MF after phototherapy, indicating these features may be important diagnostic parameters evaluating therapeutic effect of phototherapy.