Colon metastasis 20 years after the removal of ovarian cancer: Report of a case.

This report describes the case of a patient who had undergone surgery to resect bilateral ovarian tumors and then presented with colon metastasis 20 years later. A 69-year-old woman was admitted to the hospital for a clinical survey. She had been operated on for bilateral ovarian cancer in 1987 and was treated by postoperative adjuvant chemotherapy. The patient's follow-up showed no abnormality until 2006. Colonoscopy revealed an elevated irregular lesion in the cecum. A biopsy of the lesion showed a group V, moderately differentiated adenocarcinoma. A right hemicolectomy with a partial resection of the ileum and a lymphadenectomy was performed. Immunohistochemical staining during the pathological diagnosis showed the lesion to be colon metastasis from a serous papillary adenocarcinoma of the ovary. Immunohistochemical staining was positive for cytokeratin 7, carbohydrate antigen (CA)-125, and estrogen receptors, and negative for cytokeratin 20, carcinoembryonic antigen, and CA19-9. The use of immunohistochemistry demonstrated the tumor to be of ovarian origin.