T-helper cell lymphoma involving the lymph nodes and skin. A clinical, morphologic, and immunohistochemical analysis of five cases.

The clinical, morphologic, and immunohistochemical features of 5 cases of peripheral T-cell lymphoma with lymph node and skin involvement are reported. All patients were male and presented with generalized lymphadenopathy and skin lesions. Lymph node biopsy specimens showed a diffusely growing, pleomorphic, atypical lymphoid infiltrate composed of markedly irregular small and large cells. The stroma consisted of plasma cells, eosinophils, epithelioid histiocytes, and an increased number of small blood vessels. A similar neoplastic infiltrate was observed in the cutaneous nodules that developed in three patients. Immunohistochemistry on frozen tissue sections of lymph nodes using a broad panel of monoclonal antibodies revealed that the neoplastic cells were reactive with anti-T-cell antibodies, the majority of them belonging to the helper/inducer T-cell subset. Stromal plasma cells contained polyclonal immunoglobulins. It is concluded that the malignant lymphoma of peripheral helper/inducer T-cell origin observed in these five patients represents a variant of a mixed, blastic/cell T-cell lymphoma, characterized by a peculiar stromal component and skin involvement.