A case of gastric metastasis from renal cell cancer during the sequential targeted therapy

Historically, gastric metastasis from renal cell cancer (RCC) has been extremely rare. As RCC is now being treated with various agents of targeted therapy, however, the rate of unusual visceral metastases might increase as outcomes improve and follow-up periods grow longer. Here we present a valuable case of gastric metastasis from RCC detected in a routine CT scan during sequential targeted therapy. A 73-year-old man was referred to our hospital, presenting with left renal cell cancer with multiple lung metastases at stage cT1bN0M1. He received first-line targeted therapy consisting of sunitinib and subsequently underwent left radical nephrectomy. He then underwent sequential therapy consisting of interferon-alpha, sunitinib, everolimus, and axitinib for multiple lung metastases. Five years after nephrectomy, a follow-up computed tomography scan revealed a 2.2 × 1.6 cm mass in the stomach without any symptoms. Gastrointestinal endoscopy disclosed a polypoid lesion at the gastric fundus. Endoscopic submucosal resection was performed. Microscopic diagnosis revealed gastric metastasis from RCC. As various new therapeutic agents increase survival periods for metastatic RCC patients in this era of targeted therapy, clinicians must watch for metastasis in the stomach, though this was formerly a rare event.