Siddiqui, MRSMRSSiddiquiSimillis, CCSimillisHunter, CCHunterChand, MMChandBhoday, JJBhodayGarant, AAGarantTe, VVTeArtho, GGArthoRasheed, SSRasheedTekkis, PPTekkisAbulafi, A-MA-MAbulafiBrown, GGBrown2017-08-232018-04-272017-04-27BRITISH JOURNAL OF CANCER, 2017, 116 (12), pp.1513-15190007-0920http://hdl.handle.net/10044/1/49699background: Pathological extramural vascular invasion (EMVI) is an independent prognostic factor in rectal cancer, but can also be identified on MRI-detected extramural vascular invasion (mrEMVI). We perform a meta-analysis to determine the risk of metastatic disease at presentation and after surgery in mrEMVI-positive patients compared with negative tumours. methods: Electronic databases were searched from January 1980 to March 2016. Conventional meta-analytical techniques were used to provide a summative outcome. Quality assessment of the studies was performed. results: Six articles reported on mrEMVI in 1262 patients. There were 403 patients in the mrEMVI-positive group and 859 patients in the mrEMVI-negative group. The combined prevalence of mrEMVI-positive tumours was 0.346(range=0.198–0.574). Patients with mrEMVI-positive tumours presented more frequently with metastases compared to mrEMVI-negative tumours (fixed effects model: odds ratio (OR)=5.68, 95% confidence interval (CI) (3.75, 8.61), z=8.21, df=2, P<0.001). Patients who were mrEMVI-positive developed metastases more frequently during follow-up (random effects model: OR=3.91, 95% CI (2.61, 5.86), z=6.63, df=5, P<0.001). conclusions: MRI-detected extramural vascular invasion is prevalent in one-third of patients with rectal cancer. MRI-detected extramural vascular invasion is a poor prognostic factor as evidenced by the five-fold increased rate of synchronous metastases, and almost four-fold ongoing risk of developing metastases in follow-up after surgery.© 2017 Cancer Research UK. All rights reserved. Available under a Creative Commons Attribution Non-Commercial Share Alike License (https://creativecommons.org/licenses/by-nc-sa/2.5/).Science & TechnologyLife Sciences & BiomedicineOncologyextramural vascular invasionMRIrectal cancerVENOUS INVASIONCOLORECTAL-CANCERPROGNOSTIC-SIGNIFICANCEOPTIMAL CATEGORIZATIONCLINICAL-SIGNIFICANCEELASTIN-STAINFOLLOW-UPQUALITYCHEMOTHERAPYSURVIVAL1112 Oncology And CarcinogenesisOncology & CarcinogenesisJournal Articlehttps://www.dx.doi.org/10.1038/bjc.2017.991532-1827