Breast cancer often metastasises to bone, lymph nodes, liver and lung. In this case report, we present a 75-year-old woman with a suspicious mammography and ultrasound of the breast who had a synchronous painless renal lesion. On computed tomography, the renal mass was suspected of being a primary lesion of the renal pelvis, but anatomopathological examination of the nephro-ureterectomy specimen revealed that it was a metastatic deposit of invasive lobular adenocarcinoma of the breast.

(BELG J MED ONCOL 2019;13(4):132–134)