Immunologic abnormalities in a patient with multiple neoplasms.

Pernicious anemia, antithyroid antibodies, IgG(K) M component, depressed production of other immunoglobulins and impaired function of peripheral blood lymphocytes developed in a patient with adenocarcinoma of the colon, transitional-cell carcinoma of the tongue and clear-cell parathyroid adenoma. This case demonstrates that immunologic abnormalities and multiple malignant neoplasms may coexist in one patient. It lends support to the hypothesis that neoplastic processes and autoimmunity may both be related to impaired immune surveillance.