BACKGROUND: Primary colic lymphoma represents a rare disease accounting for the 0.2%-0.6% of all large-bowel malignancies. We here report a case of diffuse large B-cell lymphoma presenting as a left colic stenosis in a patient who had undergo renal transplant 23 years before. CASE REPORT: A 67-years old man presented with recurrent abdominal pain, distension, nausea and constipation since 3 weeks. His past medical history included hepatic and renal polykystose with renal transplant 23 years before. Colonoscopy revealed a non-surmountable inflammatory left colic stenosis at 55 cm from the anal verge. Biopsies demonstrated inflammatory colic mucosa without neoplastic cells. Non-enhanced CT scan and CT virtual colonoscopy were performed, showing a left colon circumferential thickening of 4 cm. Laparoscopic left colectomy was performed to treat the colic obstructive syndrome and to have complete specimen analysis. After Pathological analysis and Immunohistochemistry the diagnosis of diffuse large B cell lymphoma was established. The resection was R0. The postoperative course was uneventfully. CONCLUSION: Large B-cell lymphoma represents a rare case of bowel tumor. However it has to be considered in the differential diagnosis of colic stenosis in immunosuppressed patients as transplant recipients.