Oliguria and renal failure from a giant pelvic lymphoma.

Extranodal presentations of lymphoma typically manifest in the gastrointestinal tract, skin and central nervous system. Occurrences in the pelvic region are relatively rare and can pose significant diagnostic challenges. Our patient presented with progressive oliguria and eventually renal failure. He underwent bilateral percutaneous nephrostomy. After several scans, a colonoscopy and a percutaneous biopsy confirmation, he was treated with chemotherapy. This case highlights the diagnostic challenges faced in patients with large pelvic tumours and the importance of considering pelvic lymphoma as a possible differential diagnosis.