Clinical findings. A 68-year-old white woman developed a mildly pruritic single pink papule on her right lateral thigh. The lesion did not improve with topical antibiotics, and a shave biopsy was performed. The biopsy from a red, firm, 1-cm nodule in the left posterior calf revealed granulomatous MF.
Pathology findings. Histologic sections showed a dense atypical lymphoid infiltrate involving the dermis with multifocal epidermotropism. The lymphocytes were small to intermediate in size, some with convoluted nuclear contours. In addition, a granulomatous reaction with multinucleated giant cells and elastophagocytosis were also present. The vast majority of infiltrating atypical lymphocytes were positive for CD3 with a predominance of CD4+ cells over CD8+ cells, particularly in the epidermotropic atypical cells. Few B-cells were noted.
Molecular findings. Molecular studies confirmed the presence of a monoclonal TCR-gamma gene rearrangement (using the family V IV). Polymerase chain reaction studies for the TCR-gamma gene revealed an oligoclonal pattern.
Stage, treatment, and follow-up. Because the tumor reached the subcutaneous tissue, a 6-mm punch biopsy for a complete removal was performed at the previous biopsy site. Flow cytometry immunophenotypic studies of the peripheral blood failed to detect an aberrant T-cell population. This biopsy was negative for residual MF. She is being closely followed up with no additional treatment.