Folliculotropic Mycosis Fungoides
Folliculotropic Mycosis Fungoides (MF) - Microscopic Features: Folliculotropic MF is characterized by lymphocytic infiltrates within and surrounding the hair follicles with relative sparing of the epidermis. Most of the lymphocytes are medium to large size with cerebriform nuclei. Follicular mucinosis is a common finding caused by accumulation of acid mucopolysaccharides within the follicles. Some cases may show large cell transformation with numerous blast-type cells. Additional findings include: basal follicular hyperplasia, granulomatous inflammation (following rupture of hair follicles), eosinophils within the infiltrate, syringotropism, and cystic change in follicles.