Nodular lymphoma with intracellular immunoglobulin.

A case of malignant lymphoma with vacuolated cells is presented and, as with two other recent reports, is of the nodular poorly differentiated lymphocytic type. This form of malignant lymphoma presumably is composed of neoplastic B lymphocytes, which produce intracellular immunoglobulins or fractions thereof, corresponding to various cellular vacuoles and inclusions. The vacuolated appearance of the neoplastic cells simulates mucinous or "signet ring" adenocarcinoma, which may be excluded by clinical, routine microscopic, histochemical, immunologic, and electron microscopic observations.