title: [A rare case of colorectal micropapillary carcinoma].
abstract: Micropapillary carcinoma is regarded as an aggressive variant of adenocarcinoma in any location. It is histologically characterized by papillary cell clusters surrounded by clear spaces. The reported proportion of micropapillary carcinoma component in the entire tumor ranges from 5-80% and no pure cases have been reported. To date, there are approximately 130 cases reported in the colorectum. We recently examined a patient with a pure micropapillary carcinoma showing co-expression of CK7, CK20, and absence of CDX2, which had an aggressive tumor with extensive perineural, vascular, and lymphatic invasion as well as extensive nodal metastasis. The presence of a micropapillary carcinoma in the colorectum seemed to be closely related with nodal metastasis, as observed in micropapillary carcinomas from other organs. Thus, if a micropapillary component is identified in a tumor, particularly in a biopsy specimen, extensive surgical resection should be considered due to the high potential for nodal metastasis, even if the preoperative diagnosis is a pedunculated early colorectal cancer.
authors.affiliation: Departamento de Anatomía Patológica, Instituto Nacional de Cancerología, Secretaría de Salud, México. saul.lino.sil@gmail.com
authors.forename: Leonardo Saúl
authors.initials: LS
authors.lastname: Lino-Silva
authors.forename: Rosa Angélica
authors.initials: RA
authors.lastname: Salcedo-Hernández
mesh_terms: D002291:Carcinoma, Papillary / Q000473:pathology*; D015179:Colorectal Neoplasms / Q000473:pathology*; D006801:Humans; D008297:Male; D008875:Middle Aged