A 72-year-old man was diagnosed with chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL) and signet ring cell carcinoma in a gastric biopsy. He underwent a subtotal gastrectomy + lymphadenectomy + chemotherapy + radiotherapy. He did not receive treatment for the lymphoma. Eight years after the diagnosis, he presented with alternating diarrhea and constipation. Physical examination revealed bilateral laterocervical, axillary, and inguinal lymphadenopathies. The laboratory results showed LDH: 286 UI/l and Beta-2-microglobulin: 6.4 mg/L. CT scan showed a mass that seems to involve the cecum and terminal ileum with multiple locoregional, retroperitoneal, and mesenteric lymphadenopathies. He underwent a right hemicolectomy. Macroscopically, we identified an ulcerated mass of approximately 7 x 6 x 5 cm. in the cecum. The microscopic findings were consistent with chronic lymphocytic leukemia (CD20+ and CD5+) with scattered Hodgkin reed Sternberg-like cells CD30 and EBER+ (Epstein-Barr virus-encoded RNA) by in situ hybridization (ISH) positive (Fig. 1). The patient received treatment with mini-CHOP chemotherapy (cyclophosphamide, doxorubicin, vincristine, and prednisolone) plus rituximab with partial response after the third cycle.