A case of liver metastasis arising from gastric GIST 12 years after resection of primary GIST

Abstract

Liver is the most common site for metastasis of gastrointestinal stromal tumors (GIST). Liver metastasis often occurs within 2 years of a primary GIST resection. We describe an 80-year-old male patient with liver metastasis from a GIST resected 12 years ago. He was admitted for examination of the liver tumor, having previously had a partial gastrectomy for a gastric submucosal tumor. Abdominal enhanced CT revealed an irregular, heterogenous tumor, 75 mm in diameter, in the right lobe.
Contrast-enhanced ultrasonography using Sonazoid indicated irregular hyper-enhancement in the vascular phase and hypoecho in the Kupffer phase. We diagnosed a metastatic liver tumor or cholangiocellular carcinoma and performed a right hepatectomy. Microscopic examination revealed that the tumor consisted of uniform and spindle cells with a fascicular growth pattern. Immunohistochemically, c-kit and CD34 were expressed. The tumor was diagnosed as a metastasis of the GIST, the gastric submucosal tumor resected 12 years ago.