Lymphoma of the skin. A comparative clinico-pathologic study of 50 cases including mycosis fungoides and primary and secondary cutaneous lymphoma.

A clinico-pathologic study of lymphomas of the skin included 14 cases of mycosis fungoides, 14 of primary lymphoma and 22 of secondary lymphoma. Mycosis fungoides has clinical and histopathologic features which allow for separation from the other groups. In this study, patients with mycosis fungoides had a longer duration of history and presented with papules, plaques, erythroderma or generalized dermatitis but not with tumor nodules ab initio. A confident histologic diagnosis required the presence of the mycosis cell, which was usually present in association with a mixed inflammatory cell infiltrate. Another important histologic feature was the presence of invasion of the epidermis by the mycosis cells singly and/or in nests (Pautrier microabscesses). Primary and secondary lymphomas of the skin presented clinically as multiple tumor nodules and histologically as a monomorphic infiltrate of neoplastic cells confined to the dermis and subcutis. A feature which has not been adequately documented in a large series was the presence of an associated prominent epithelioid cell reaction in several cases from all three groups.