Retrospective Study
Copyright ©The Author(s) 2018. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Sep 14, 2018; 24(34): 3919-3926
Published online Sep 14, 2018. doi: 10.3748/wjg.v24.i34.3919
Predicting the presence of adenomatous polyps during colonoscopy with National Cancer Institute Colorectal Cancer Risk-Assessment Tool
Hassan Tariq, Muhammad Umar Kamal, Harish Patel, Ravi Patel, Muhammad Ameen, Shehi Elona, Maram Khalifa, Sara Azam, Aiyi Zhang, Kishore Kumar, Ahmed Baiomi, Danial Shaikh, Jasbir Makker
Hassan Tariq, Harish Patel, Kishore Kumar, Jasbir Makker, Division of Gastroenterology, Department of Medicine, BronxCare Health system, Bronx, NY 10457, United States
Muhammad Umar Kamal, Ravi Patel, Muhammad Ameen, Shehi Elona, Maram Khalifa, Sara Azam, Aiyi Zhang, Ahmed Baiomi, Danial Shaikh, Department of Medicine, BronxCare Health system, Bronx, NY 10457, United States
Author contributions: Tariq H, Kamal MU, Patel H and Makker J contributed to concept and design; Patel R, Ameen M, Shehi E, Khalifa M and Azam S contributed to acquisition of data; Tariq H, Kamal MU, Patel H, Zhang A and Makker J contributed to analysis and interpretation of data; Tariq H, Kamal MU, Patel H, Baiomi A, Shaikh D and Makker J drafted the manuscript, Tariq H, Kamal MU, Patel H, Kumar K and Makker J contributed to critical revision of the manuscript for important intellectual content; Zhang A performed statistical analysis; Patel H, Baiomi A and Makker J contributed to study supervision.
Institutional review board statement: The study was performed in agreement with the ethical guidelines of the Declaration of Helsinki and the protocol was approved by the local Ethics Committee (IRN# 12 14 17 13).
Informed consent statement: All participants have given written informed consent before inclusion in the study.
Conflict-of-interest statement: All authors declare no financial support or conflict of interest.
Data sharing statement: The raw data used for all analyses are available from the corresponding author.
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: Muhammad Umar Kamal, MD, Doctor, Resident Physician, Department of Medicine, BronxCare Health system, 1650 Selwyn Avenue, Apt 10C, Bronx, NY 10457, United States. muhammadumarkamal@gmail.com
Telephone: +1-718-9601234 Fax: +1-718-9602055
Received: July 2, 2018
Peer-review started: July 3, 2018
First decision: July 18, 2018
Revised: July 25, 2018
Accepted: August 1, 2018
Article in press: August 1, 2018
Published online: September 14, 2018
Processing time: 74 Days and 3.6 Hours
ARTICLE HIGHLIGHTS
Research background

Colorectal cancer (CRC) is the third most common cancer diagnosed in men and women in the United States. The lifetime risk for developing CRC is 1 in 22 for men and 1 in 24 for women. Estimates for new cases of CRC amount to 140000 yearly, and approximately 50000 people will die of CRC in 2018 alone. CRC arises from colonic polyps, specifically ‘adenomas’, which result from either a sporadic mutation or a DNA mismatch repair within the mucosal lining of the intestine. Adenomas may grow and progress from low-grade dysplasia to high-grade dysplasia, to carcinoma-in-situ and eventually invasive carcinoma. It is there essential to diagnose the pre-cancerous and cancerous lesions are earlier stage.

Research motivation

Due to the financial and social impact of CRC on society, it is imperative to quantitatively assess the risk of developing CRC in individuals. Many tools are widely available that help calculate future risk of CRC, however they tend to be limited to specific patient groups, or be based on selected populations of patients, and have relatively poor discrimination or are not validated and/or published. Therefore, it is needed to developed tools which help predict future risk of CRC more specifically.

Research objectives

National Cancer Institute Colorectal Cancer Risk Assessment tool provides 5-year, 10-year and lifetime estimates and currently helps predict lifetime CRC risk. We conducted this study with the aim of evaluating the NCI Colorectal Cancer Risk Assessment Tool as a predictor of the presence of adenomatous polyps found during screening or surveillance colonoscopy.

Research methods

This is a retrospective single center observational study over a period of 6 mo duration. The data was collected from the electronic medical records of patients and tabulated in Microsoft Excel. Findings at colonoscopy were extracted from final procedure reports, and pathology information was extracted from final pathology reports. Asymptomatic patients between 50 and 80 years old, undergoing colonoscopy were included in the study population. Patients who met the above criteria were interviewed over the phone, and their lifetime NCI CRC Risk-Assessment Tool score was calculated. The predictors included in the NCI CRC Risk-Assessment Tool are number of relatives with CRC, body mass index, servings of vegetables per day, aspirin and nonsteroidal anti-inflammatory drug use, usual number of cigarettes smoked per day and years of smoking in current and former smokers, prior negative sigmoidoscopy and/or colonoscopy, polyp history and current vigorous leisure time activity etc.The authors in original paper estimated 10-year and 20-year CRC risks. This tool is available on the Internet and provides 5-year, 10-year and lifetime estimates. We used the predicted lifetime CRC risk. The data on the presence of adenomatous polyps and the numbers in each colonoscopy were collected.

Research results

After data analysis, it was noticed that the prevalence of AP increased progressively through the five quintiles of risk scores: 27.63% in the first and lowest quintile, 33.53% in the second quintiles, 46.31% in the third quintiles, 52.21% in the fourth quintile, and 51.35% in the fifth and highest quintile. The odd ratios (ORs) of AP prevalence in the third quintile compared to the first and second quintile were 2.26 (CI: 1.40-3.65) and 1.71 (CI: 1.08-2.70). The ORs of AP prevalence in the fourth quintile compared to the first and second quintile were 2.86 (CI: 1.75-4.67) and 2.16 (CI: 1.36-3.45). Youden’s Index indicated the optimal risk score cutoff value discriminating AP prevalence status was 3.60 based on data on all patients. The percentage of AP prevalence patients was smaller for patients with risk score lower than 3.6 compared to the patients with risk score 3.6 and above (30.8% vs 52.7%, P < 0.001). The percentage of patients having three and more adenomas is smaller for patients with risk score less than 3.6 compared to patients with risk score 3.6 and above (4.8% vs 14.6%, P < 0.001).

Research conclusions

According to this study, patients with the higher NCI risk score have higher risk of AP and subsequent CRC. Our findings propose that patients who are categorized as high risk according to the NCI CRC risk assessment tool should undergo colonoscopy for the screening of CRC. Our study also revealed that the NCI CRC risk assessment tool can predict about the presence of AP, in addition to the lifetime risk of CRC. In these high risk patients, the measures to increase the effectiveness of CRC detection in these patients include longer withdrawal time, early surveillance colonoscopy, and choosing flexible colonoscopy over other CRC screening modalities. This study characterized the risk of future CRC risk and AP based on NCI score and will assist the patients and providers with informed decision-making about timing and mode of screening.

Research perspectives

In the last two decades, screening and surveillance colonoscopy guidelines implementation has remarkably decreased the CRC incidence and mortality. Our study was conducted to further decrease the morbidity and mortality associated with CRC. The tool can be used to predict the risk of future CRC and AP and therefor can assist the patients and providers with informed decision-making about timing and mode of screening. To further validate the results of our study, there is a need to conduct prospective trials in a larger and heterogeneous population group with more diverse racial and ethnic backgrounds and involving multiple center.