Diffuse T-cell lymphoma preceded by nodular lymphoma.

A patient with a nodular lymphoma morphologically indistinguishable from follicular B-cell lymphoma subsequently developed a diffuse T-cell lymphoma. This T-cell lymphoma displayed characteristics analogous to mature T-lymphocytes, and typed as a suppressor/cytotoxic T-cell with the monoclonal antibodies. The light and electron microscopy morphology of the T-cell lymphoma was similar to that reported for node-based T-cell lymphomas. There was a polymorphous proliferation of variably transformed lymphocytes including immunoblasts. This case could represent either a nodular form of T-cell lymphoma converting to a diffuse T-cell lymphoma, or a follicular B-cell lymphoma preceding, and possibly inducing, a suppressor T-cell lymphoma.