{"entity":{"id":"colorectal-micropapillary-carcinoma","kind":"cancer","name":"Micropapillary adenocarcinoma of the colon and rectum","aka":["Micropapillary adenocarcinoma of the colon and rectum (small tumour nests with reversed polarity; heavy lymphatic and vascular invasion)","Colorectal micropapillary carcinoma","Micropapillary colorectal cancer","Colorectal carcinoma with micropapillary pattern"],"tldr":"Micropapillary adenocarcinoma is bowel cancer in which some of the tumour grows as tiny clusters of cells floating in empty spaces, with the cells turned inside out so the surface that normally faces the bowel faces outwards instead. It is a pattern that goes with heavier invasion of lymph and blood vessels and more involved lymph nodes, and it is graded and treated like ordinary bowel cancer.","summary":"What it is. The 2019 World Health Organization classification of digestive tumours lists micropapillary adenocarcinoma among the histological subtypes of colorectal adenocarcinoma (Nagtegaal 2020). Under the microscope the tumour forms small morula-like nests of cells without a fibrovascular core, sitting in empty lacunar spaces, and the cells show reversed polarity: the apical membrane faces the stroma rather than a lumen, which can be shown by staining for villin or epithelial membrane antigen (Oncol Lett 2021).\n\nHow it differs from its parent. The micropapillary component is almost never the whole tumour. Reported proportions range from 5 to 80 percent of a lesion and are usually under 30 percent (J Gastrointest Cancer 2026). Where it is present, tumours show more lymphatic and vascular invasion, a higher ratio of involved to examined lymph nodes and a higher pathological T category than colorectal cancers without it, and more invasion again as the proportion rises (Hum Pathol 2018). KRAS, BRAF and TP53 mutations are described in the pattern and are read as driving invasiveness and the loss of polarity rather than defining a separate disease (J Gastrointest Cancer 2026).\n\nHow common it is. In 266 colorectal cancers the pattern was found in 27.8 percent at any extent and in 9.4 percent at 5 percent or more of the tumour (Hum Pathol 2018); in 453 tumours the 5 percent threshold was met in 19.8 percent (Oncol Lett 2021). Counts depend entirely on the threshold used, and no national registry records it.\n\nHow it is treated. No trial has been run in this histology. Treated as colorectal adenocarcinoma: resection with adjuvant chemotherapy by stage when removable, the systemic rows of the parent page when not; the parent record carries the trials. The practical consequence of the report is staging: the pattern travels with node involvement, so it is a reason to look carefully at the nodes and the margins rather than a reason to change the drugs.","asOf":"2026-09-24","wikipedia":"https://en.wikipedia.org/wiki/Colorectal_cancer","links":[{"label":"Nagtegaal, Histopathology 2020: the 2019 WHO classification of tumours of the digestive system","url":"https://doi.org/10.1111/his.13975"},{"label":"Hum Pathol 2018: the clinicopathological significance of micropapillary pattern in colorectal cancers (266 tumours)","url":"https://doi.org/10.1016/j.humpath.2018.02.027"},{"label":"Oncol Lett 2021: villin as a biomarker for reverse polarity in colorectal micropapillary carcinoma (453 tumours)","url":"https://doi.org/10.3892/ol.2020.12333"},{"label":"J Gastrointest Cancer 2026: colorectal micropapillary adenocarcinoma, molecular mechanisms and clinical implications (review)","url":"https://doi.org/10.1007/s12029-025-01372-z"},{"label":"NICE NG151: colorectal cancer, recommendations (Lynch 1.1, local disease 1.3, biomarkers 1.4, metastatic disease 1.5, ongoing care and support including follow-up 1.6)","url":"https://www.nice.org.uk/guidance/ng151/chapter/Recommendations"}],"tags":["gi","colorectal","subtype-page"],"related":["colorectal","colorectal-adenoma-like-adenocarcinoma","colorectal-mucinous-adenocarcinoma","colorectal-serrated-adenocarcinoma","colon-cancer","rectal-cancer"],"cancers":[],"sections":[],"technologies":["histopathology-ihc"],"targets":[],"drugs":[],"companies":[],"institutions":[],"pathways":[],"terms":["tumour-grade","tnm-staging","circumferential-resection-margin"],"trials":[],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":[],"group":"gastrointestinal","burden":"A pattern rather than a separate tumour in most series. In 266 Korean colorectal cancers a micropapillary pattern of any extent was present in 27.8 percent and made up 5 percent or more of the tumour in 9.4 percent; in a later series of 453 tumours the 5 percent threshold was met in 19.8 percent. No UK or registry count is published.","subtypes":["Colorectal adenocarcinoma with a focal micropapillary component (under 5 percent of the tumour)","Colorectal adenocarcinoma with a substantial micropapillary component (5 percent or more, the threshold most series use)","Micropapillary pattern arising within mucin pools (distinguished from pure micropapillary pattern)"],"biomarkers":["Micropapillary component as a percentage of the tumour, recorded in the pathology report","Reversed polarity shown by villin, epithelial membrane antigen or E-cadherin staining","Lymphatic and vascular invasion, which travel with the pattern"],"standardOfCare":[{"setting":"Localised disease","approach":"Resection with the usual nodal harvest; adjuvant chemotherapy decided by stage as for colorectal adenocarcinoma of no special type, with the node involvement that travels with this pattern taken into account.","refs":["colectomy","total-mesorectal-excision","capox","folfox"],"guideline":{"version":"NICE NG151: colorectal cancer (published January 2020, last updated December 2021, last reviewed April 2026)","url":"https://www.nice.org.uk/guidance/ng151"}}],"stateOfArt":[],"history":[],"pipeline":[],"openProblems":[],"parent":"colorectal"},"route":"/cancers/colorectal-micropapillary-carcinoma/","neighbours":{"cancer":[{"id":"colorectal-adenoma-like-adenocarcinoma","kind":"cancer","name":"Adenoma-like adenocarcinoma of the colon and rectum","route":"/cancers/colorectal-adenoma-like-adenocarcinoma/"},{"id":"colon-cancer","kind":"cancer","name":"Colon cancer (adenocarcinoma of the colon)","route":"/cancers/colon-cancer/"},{"id":"colorectal","kind":"cancer","name":"Colorectal cancer","route":"/cancers/colorectal/"},{"id":"colorectal-mucinous-adenocarcinoma","kind":"cancer","name":"Mucinous adenocarcinoma of the colon and rectum","route":"/cancers/colorectal-mucinous-adenocarcinoma/"},{"id":"rectal-cancer","kind":"cancer","name":"Rectal cancer","route":"/cancers/rectal-cancer/"},{"id":"colorectal-serrated-adenocarcinoma","kind":"cancer","name":"Serrated adenocarcinoma of the colon and rectum","route":"/cancers/colorectal-serrated-adenocarcinoma/"}],"technology":[{"id":"histopathology-ihc","kind":"technology","name":"Histopathology & immunohistochemistry","route":"/technologies/histopathology-ihc/"}],"term":[{"id":"circumferential-resection-margin","kind":"term","name":"Circumferential resection margin (rectal cancer)","route":"/terms/circumferential-resection-margin/"},{"id":"colectomy","kind":"term","name":"Colectomy","route":"/terms/colectomy/"},{"id":"tumour-grade","kind":"term","name":"Grade","route":"/terms/tumour-grade/"},{"id":"tnm-staging","kind":"term","name":"TNM staging","route":"/terms/tnm-staging/"},{"id":"total-mesorectal-excision","kind":"term","name":"Total mesorectal excision (TME)","route":"/terms/total-mesorectal-excision/"}],"drug":[{"id":"capox","kind":"drug","name":"CAPOX (capecitabine, oxaliplatin)","route":"/drugs/capox/"},{"id":"folfox","kind":"drug","name":"FOLFOX (5-FU, leucovorin, oxaliplatin)","route":"/drugs/folfox/"}]}}