title: Submucosal invasive micropapillary carcinoma of the colon with massive lymph node metastases: a case report.
abstract: Micropapillary carcinoma was originally reported to be an aggressive variant of breast carcinoma, and it is associated with frequent lymphovascular invasion and a dismal clinical outcome. It has subsequently been found in other organs; however, at present, only a limited number of cases of colorectal micropapillary carcinoma have been reported. We present a case of early colon cancer with extensive nodal metastases in a Japanese patient. An 82-year-old man was found by colonoscopy to have a 20-mm pedunculated polyp in his sigmoid colon. Endoscopic resection of the sigmoid colon tumor was performed, and pathological examination of the resected specimen revealed a poorly differentiated adenocarcinoma component and a micropapillary component. Despite the tumor being confined within the submucosa, massive lymphatic invasion was noted. Thereafter, the patient underwent laparoscopic sigmoidectomy with lymph node dissection, and multiple lymph node metastases were observed. Our case suggests that when a micropapillary component is identified in a pre-operative biopsy specimen, even for early colorectal cancer, surgical resection with adequate lymph node dissection would be required because of the high potential for nodal metastases.
authors.affiliation: Department of Gastroenterological Surgery, Hiroshima University Hospital, Hiroshima, Japan.
authors.forename: Shoichiro
authors.initials: S
authors.lastname: Mukai
authors.forename: Yuji
authors.initials: Y
authors.lastname: Takakura
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Egi
authors.forename: Takao
authors.initials: T
authors.lastname: Hinoi
authors.forename: Yasufumi
authors.initials: Y
authors.lastname: Saito
authors.forename: Naoki
authors.initials: N
authors.lastname: Tanimine
authors.forename: Masashi
authors.initials: M
authors.lastname: Miguchi
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Adachi
authors.forename: Manabu
authors.initials: M
authors.lastname: Shimomura
authors.forename: Hideki
authors.initials: H
authors.lastname: Ohdan
keywords: Lymph node metastases; Micropapillary carcinoma; Submucosal colonic cancer