Retrospective Study
Copyright ©The Author(s) 2016. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Aug 21, 2016; 22(31): 7157-7165
Published online Aug 21, 2016. doi: 10.3748/wjg.v22.i31.7157
Prognostic significance of computed tomography-detected extramural vascular invasion in colon cancer
Xun Yao, Su-Xing Yang, Xing-He Song, Yan-Cheng Cui, Ying-Jiang Ye, Yi Wang
Xun Yao, Su-Xing Yang, Xing-He Song, Yi Wang, Department of Radiology, Peking University People’s Hospital, Beijing 100044, China
Yan-Cheng Cui, Ying-Jiang Ye, Department of Gastrointestinal Surgery, Peking University People’s Hospital, Beijing 100044, China
Author contributions: Yao X collected and analyzed the data and drafted the manuscript; Yang SX and Song XH provided analytical oversight; Cui YC and Ye YJ offered material support; Wang Y designed and supervised the study and reviewed the final revision of the manuscript; all authors have read and approved the final version to be published.
Institutional review board statement: This retrospective study was approved by our local institutional review board, which waived the requirement for obtaining informed consent.
Conflict-of-interest statement: None of the authors have any conflicts of interest to declare.
Data sharing statement: No additional data are available.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Yi Wang, MD, PhD, Professor, Department of Radiology, Peking University People’s Hospital, No. 11 Xizhimen South Street, Xicheng District, Beijing 100044, China. wangyi@pkuph.edu.cn
Telephone: +86-13331183901 Fax: +86-10-68318386
Received: April 12, 2016
Peer-review started: April 14, 2016
First decision: May 12, 2016
Revised: May 26, 2016
Accepted: June 15, 2016
Article in press: June 15, 2016
Published online: August 21, 2016
Abstract

AIM: To compare disease-free survival (DFS) between extramural vascular invasion (EMVI)-positive and -negative colon cancer patients evaluated by computed tomography (CT).

METHODS: Colon cancer patients (n = 194) undergoing curative surgery between January 2009 and December 2013 were included. Each patient’s demographics, cancer characteristics, EMVI status, pathological status and survival outcomes were recorded. All included patients had been routinely monitored until December 2015. EMVI was defined as tumor tissue within adjacent vessels beyond the colon wall as seen on enhanced CT. Disease recurrence was defined as metachronous metastases, local recurrence, or death due to colon cancer. Kaplan-Meier analyses were used to compare DFS between the EMVI-positive and -negative groups. Cox’s proportional hazards models were used to measure the impact of confounding variables on survival rates.

RESULTS: EMVI was observed on CT (ctEMVI) in 60 patients (30.9%, 60/194). One year after surgery, there was no statistically significant difference regarding the rates of progressive events between EMVI-positive and -negative patients [11.7% (7/60) and 6.7% (9/134), respectively; P = 0.266]. At the study endpoint, the EMVI-positive patients had significantly more progressive events than the EMVI-negative patients [43.3% (26/60) and 14.9% (20/134), respectively; odds ratio = 4.4, P < 0.001]. Based on the Kaplan-Meier method, the cumulative 1-year DFS rates were 86.7% (95%CI: 82.3-91.1) and 92.4% (95%CI: 90.1-94.7) for EMVI-positive and EMVI-negative patients, respectively. The cumulative 3-year DFS rates were 49.5% (95%CI: 42.1-56.9) and 85.8% (95%CI: 82.6-89.0), respectively. Cox proportional hazards regression analysis revealed that ctEMVI was an independent predictor of DFS with a hazard ratio of 2.15 (95%CI: 1.12-4.14, P = 0.023).

CONCLUSION: ctEMVI may be helpful when evaluating disease progression in colon cancer patients.

Keywords: Colon cancer, Extramural vascular invasion, Disease-free survival, Neoplasm invasion, Risk assessment

Core tip: The 4-point computed tomography extramural vascular invasion (ctEMVI) detection and grading system has been described and validated as a method for predicting disease-free survival (DFS) in colon cancer patients. In this study, we assess the difference in DFS between ctEMVI-positive and -negative colon cancer patients. ctEMVI status as well as pathological T and N status were independent adverse prognostic indicators for colon cancer patients. ctEMVI, in conjunction with the extent of extramural spread and lymph node burden, may become a novel and clinically significant imaging evaluation parameter when deciding whether patients with colon cancer should receive neoadjuvant treatment.