To perform case series from one centre over 9 years, and review of the literature. The synchronous diagnosis of colorectal malignancy and lymphoma is rare.Case note review of patients identified from clinical databases.Five patients were identified and findings discussed. In two patients colorectal malignancy staging CT scans identified pathological lymphadenopathy consistent with lymphoma. A further two patients had an incidental lymphoma on histological examination of the colorectal malignancy specimen. The fifth patient was found to have suspicious superior mesenteric lymph nodes at laparotomy. Histology confirmed two nodular lymphocyte-predominant Hodgkin's lymphomas, a lymphocytic-rich classical Hodgkin's lymphoma, a diffuse large B-cell lymphoma and a B-cell follicular lymphoma.There is a need for vigilance for the possibility of dual pathologies in all specialties.