Contralateral Adrenal Metastasis of Renal Cell Carcinoma Arising From a Horseshoe Kidney: An Initial Case Report☆

A 71-year-old woman with a right adrenal mass detected by computed tomography was referred to our institution. Before 33 months, she had undergone a radical heminephrectomy for an 11-cm renal cell carcinoma (RCC) in the left moiety of a horseshoe kidney. The adrenal tumor was diagnosed as the metastasis of RCC. The tumor was subsequently removed in a laparoscopic adrenalectomy by a retroperitoneal approach. Pathologic examination revealed the mass to be the adrenal metastasis of RCC. To our knowledge, this is the initial report of a laparoscopic adrenalectomy for the adrenal metastasis of renal cell carcinoma arising from a horseshoe kidney.