Bellini duct carcinoma of the kidney masquerading as an iliac bone tumour in an adult Nigerian

Bellini Duct Carcinoma (BDC) of the Kidney is a rare type of Renal Cell Carcinoma. It usually presents with features of local advancement or metastasis and rarely diagnosed incidentally. We present a case report of a young man who was found to have BDC of the Right Kidney following presentation with an iliac bone tumour. A 40 year old man presented to the Orthopaedic outpatient clinic on account of right sided pelvic pain and limping following a trivial fall at home. There was no antecedent history of loin pain, loin mass or haematuria. On evaluation, he was found to have a huge right iliac bone tumour invading the contiguous muscles. An incidental hypodense central ipsilateral renal mass with enlarged peri-hilar lymph nodes were found. He subsequently had right radical nephrectomy via a right sub-coastal approach and wide local excision of the Iliac bone tumour in two separate procedures. The resection margins were negative for tumour cells. Histology of the resected specimens were consistent with a metastatic right BDC of the kidney. He had a smooth post-operative recovery. One third of BDC of the kidney presents with metastasis. A high index of suspicion is required in order to diagnose BDC following such unusual presentations.