Granulomatous mycosis fungoides. Clinicopathologic study of two cases.

Granulomatous mycosis fungoides is a rare form of mycosis fungoides with controversial histogenesis. Early reports seemed to indicate a favorable prognosis for these patients. We report two cases of granulomatous mycosis fungoides, both of which had other unusual clinical features. The cases were studied with routine light microscopy, immunohistochemistry, electron microscopy, and gene probe studies. Despite some clinical and histopathologic similarities, the results of the immunohistochemical and molecular biologic studies were diverse. These results suggest that granulomatous mycosis fungoides does not define a single subset of cases, immunophenotypically or biologically.