Mycosis fungoides with follicular mucinosis displaying aggressive tumor-stage transformation: Successful treatment using radiation therapy plus oral bexarotene combination therapy

Follicular mucinosis is a tissue reaction pattern characterized by mucin deposition with follicular sebaceous units and is found as an idiopathic, primary, benign process (alopecia mucinosa), or as a secondary process due to inflammatory and neoplastic disorders (mycosis fungoides). When associated with follicular mucinosis, mycosis fungoides commonly pursues an aggressive course, often undergoing large-cell transformation, which is associated with resistance to therapy and poor prognosis. We present a case of mycosis fungoides with follicular mucinosis that was treated with incomplete courses of interferon, isotretinoin, and polychemotherapy with subsequent rapid progression to tumor-stage mycosis fungoides with large cell transformation and nodal and bone marrow involvement. In this setting, the patient was treated with local radiation therapy, total-skin electron beam therapy, and therapy and maintenance with the oral retinoid-X-receptor retinoid bexarotene, and achieved a durable complete remission.