Multiple Primary Cancers: Primary Malignant Lymphomas and Carcinomas of the Intestinal Tract in the Same Patient.

Three cases of primary malignant lymphoma and primary mucus-secreting adenocarcinoma of the intestinal tract, occurring in the same patients, are described, and three similar cases reported in the literature are discussed. The carcinomas were present at the same time as the lymphomas, or developed after the lymphomas had been removed. The relationship between malignant lymphoma and carcinoma is uncertain, but there is some evidence to suggest a possible relationship between them. It is important not to assume that a second growth in the intestinal tract is always a recurrence or a metastasis from the original primary tumour.