[Case of small early cancer of sigmoid colon, which recurred with liver metastasis 18 months after surgical resection].

A 74-year-old man was referred to our hospital with positive fecal occult blood test. Colonoscopic examination revealed a 7-mm 0-Is type polyp in the sigmoid colon. Endoscopic mucosal resection for this lesion completely removed the lesion and the histologic diagnosis was well differentiated adenocarcinoma. Cancer cells invaded the submucosa to a depth of 900 microm, and vascular invasion was found. Therefore, the patient underwent additional surgical resection with lymph node dissection. During follow-up, however, serum CEA increased beyond the normal limit 18 months after surgical operation, and a 15-mm single liver metastasis was found through enhanced CT scan abdominal imaging, the FDG-PET scan, and ultrasonography. We have to pay attention to metachronous liver metastasis especially when the vascular invasion is suspected in the resected sample, even if the lesion is completely removed.