[Cases of Three Patients with Gastric Cancer and Metastasis to the Skeletal Muscle].

Metastasis to the skeletal muscle from gastric cancer is relatively rare. We report cases of 3 patients undergoing chemotherapy for gastric cancer with metastasis to the skeletal muscle. Case 1: A man in his 70s was diagnosed with advanced gastric cancer (cT4N3M1P0, stage IV), with metastasis to the lung, brain, lymph node, and iliopsoas muscle. Case 2: A man in his 60s was diagnosed with advanced gastric cancer (cT3N3M1P0, stage IV), with metastasis to the brain, lung, lymph node, and iliopsoas muscle. Case 3: A man in his 50s was diagnosed with advanced gastric cancer (cT4N3M1P0, stage IV), with metastasis to the urinary duct, lymph node, back muscle, and iliopsoas muscle. All 3 patients died within 7-8 months after the diagnosis due to progressive disease despite chemotherapy. The prognosis of these 3 patients was significantly poorer than that of patients in our hospital with metastasis not involving the skeletal muscle (p<0.01). Accordingly, metastasis to the skeletal muscle may be an adverse prognostic factor in gastric cancer.