A resected case of asynchronous liver metastasis from rectal carcinoid tumor limited to sm invasion twelve years later from resection of the primary

A 58-year-old man admitted for a liver tumor 8cm in diameter had had low anterior resection of the rectum for a carcinoid tumor 13mm in diameter with invasion to the submucosal layer in 1994. Computed tomography (CT), magnetic resonance imaging (MRI) and angiography of the abdomen revealed a lobulated mass of 8cm with tumor embolism of the portal vain in the right lobe of the liver. We diagnosed liver metastasis from the rectal carcinoid tumor on biopsy, conducting extended right hepatic lobectomy in February, 2006. Histologicaly, the tumor was metastasis from a rectal carcinoid. Liver metastasis from a rectal carcinoid less than 2cm in diameter and limited to the submucosal layer is rare, with 32 cases, including ours, recorded. This is, to our knowledge, the first to be reported in Japan that recurred after such a long term as 12 years. We should be careful of the metachronous liver metastasis when we follow up treatment for rectal carcinoid.