Lymphomas of the mucosa-associated lymphoid tissue. Signet ring cell lymphomas presenting in mucosal lymphoid organs.

Four cases of lymphoma are reported which were postulate to have developed from neoplastic transformation of the lymphoid cells of the mucosa-associated lymphoid tissue (MALT). This contention is primarily based on two observations: the peculiar "homing" tendency of these lymphomas and the immunoglobulin isotype. Both properties are characteristic of the lymphoid cells of the MALT. These lymphomas can also be identified by their histologic structure (signet ring cell lymphomas) and their presentation in an MALT organ. These lymphomas are probably separable from other lymphomas proposed to arise from lymphocytes of the gut-associated lymphoid system (GALT).