Scleromyxedematous Changes in a Patient With Long-Standing Mycosis Fungoides Who Progressed to Sézary Syndrome.

Mycosis fungoides (MF) variants with different clinicopathologic and immunohistochemical features have been well-delineated. We report a case of scleromyxedematous changes arising in a patient with long-standing MF who progressed to Sézary syndrome (SS) shortly afterward. Total-skin electron-beam radiation therapy resulted in an excellent response, controlling both the MF/SS and the scleromyxedematous lesions; however, the patient died few months later. Although mucin deposition has been described in association with MF/SS (mainly follicular mucinosis in folliculotropic MF), there are limited reports in the literature on dermal mucinosis and scleromyxedematous changes in MF/SS. The mechanism of this association and its prognostic implications requires further investigation.