Clinicopathologic profile of hypopigmented mycosis fungoides in India.

Background Hypopigmented mycosis fungoides (HMF) is an under recognized disease in India, which is often mistaken for Hansen disease or vitiligo, resulting in delayed diagnosis and treatment. Aim To describe the clinical, histopathologic and immunohistochemical features of HMF in Indian patients. Materials and methods All cases presenting as hypopigmented lesions that were signed out as MF between 2001 and 2009 (15 cases) were included. Clinical data and histopathology slides were reviewed. Immunostains for CD4, CD8, and CD1a were done, where tissue was available. Results The age ranged from 14 to 38 years with a male preponderance. The commonest presentation was multiple hypopigmented patches on limbs and trunk with the duration of the lesions varying from 4 months to 14 years. All cases showed a psoriasiform/lichenoid epidermal pattern, disproportionate epidermotropism, basilar tagging of lymphocytes, monomorphous lymphocytes, haloed lymphocytes, and wiry dermal collagen. Other important findings were infiltration of hair follicles, larger epidermal lymphocytes, atypia of dermal lymphocytes, and stuffed dermal papillae. Dermal edema was absent in all cases. Immunohistochemistry done on 10 cases showed a CD8 phenotype in 6 cases and CD4 phenotype in the remaining 4 cases. Conclusions Histopathology supplemented by immunohistochemistry is reliable in making a diagnosis of HMF. It is important to be aware of this uncommon, yet significant disease.