Subcutaneous mycosis fungoides.

In five cases of mycosis fungoides, previously treated with electron-beam therapy, subcutaneous nodules developed. Clinically, these lesions were thought to be epidermoid cysts or lipomas, but on biopsy were discovered to be subcutaneous infiltrates, three of which were diagnosed as mycosis fungoides. The other two specimens showed only a nonspecific subcutaneous infiltrate. There is no ready explanation for the appearance of these lesions, but it is speculated that they may be the result of inadequate penetration of the electron beam to the depth at which some atypical cells may originally have been located. Patients with mycosis fungoides who develop unusual subcutaneous nodules should be fully investigated so that appropriate and adequate therapy may be initiated.