[A Case of Left Renal Cell Carcinoma with Renal Arteriovenous Fistula and Multiple Vascular Malformation Undergoing Nephrectomy].

A 69-year-old woman was referred to our hospital for the treatment of a left renal tumor found by computed tomography (CT) during examination for microscopic hematuria. Contrast-enhanced CT showed a 5 cm tumor in the inferior pole of the left kidney. Left renal cell carcinoma (RCC) (cT1bN0M0) was suspected. In addition, the left renal and gonadal veins were dilated and enhanced in an arterial phase; renal arteriovenous fistula (RAVF) was suspected. Moreover, there were multiple focal arterial dilatations, suggesting the presence of multiple vascular malformation. Hereditary aortic disease, including vascular Ehlers-Danlos syndrome (vEDS), was a concern. In general, surgery is not recommended for patients with vEDS, due to vascular fragility. As such, a panel analysis of genes for hereditary aortic diseases, including vEDS, was performed; no pathogenic variants in candidate genes including COL3A1 were identified. After detailed discussions with the patient, she underwent a left nephrectomy, following transcatheter arterial embolization (TAE) of the left renal artery. We prepared a balloon catheter for aortic occlusion as a preventative measure for massive bleeding; this was not the case, as only a small amount of intraoperative bleeding occurred. Thus, the nephrectomy was performed successfully without using the balloon catheter. The patient recovered uneventfully and was discharged on day 8. Pathological examination showed clear-cell RCC (pT1a) and a RAVF near the tumor. Herein we report this case of left RCC with RAVF and multiple arterial malformation, which was successfully managed by evaluating preoperative risks with a genetic test, followed by TAE of the renal artery and open nephrectomy.