Case Control Study
Copyright ©The Author(s) 2017. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastrointest Endosc. Sep 16, 2017; 9(9): 464-470
Published online Sep 16, 2017. doi: 10.4253/wjge.v9.i9.464
Clinical predictors for sessile serrated polyposis syndrome: A case control study
Yang Wu, Alexander Mullin, Alina Stoita
Yang Wu, Alina Stoita, Department of Gastroenterology and Hepatology, St Vincent’s Hospital, University of NSW, Sydney, NSW 2010, Australia
Alexander Mullin, University of Notre Dame, Sydney, NSW 2010, Australia
Author contributions: All authors contributed to the manuscript; Wu Y and Stoita A designed the study; Wu Y and Mullin A performed data collection; Wu Y performed statistical analysis with supervision from statistical consulting unit Stats Central at University of NSW; Wu Y wrote the manuscript and Alina Stoita edited the manuscript.
Institutional review board statement: The study was approved by the Institutional Review Board. St Vincent’s Hospital Research office approved of the study as a low negligible risk research project.
Informed consent statement: Patients were not required to give informed consent to the study because the analysis used anonymous clinical data that were obtained after each patient agreed to treatment by written consent.
Conflict-of-interest statement: There is no conflict of interest.
Data sharing statement: Technical appendix, statistical code, and dataset available from the corresponding author at astoita@stvincents.com.au. Consent was not obtained but the presented data are anonymized and risk of identification is low.
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: Dr. Yang Wu, Department of Gastroenterology and Hepatology, St Vincent’s Hospital, University of NSW, 390 Victoria St, Darlinghurst, Sydney, NSW 2010, Australia. yangwu_22@hotmail.com
Telephone: +61-2-8382111 Fax: +61-2-83823983
Received: February 28, 2017
Peer-review started: March 2, 2017
First decision: May 26, 2017
Revised: June 15, 2017
Accepted: July 14, 2017
Article in press: July 17, 2017
Published online: September 16, 2017
Abstract
AIM

To compared individuals with serrated polyposis syndrome (SPS) to those with sessile serrated adenoma (SSA) and adenomas in the setting of endoscopists with high adenoma detection rates at a secondary and tertiary academic centre.

METHODS

Retrospectively we collated the clinical, endoscopic and histological features of all patients with SPS at St Vincent’s public and private hospital in the last 3 years. Patients were identified by searching through 2 pathology databases. Variables explored included smoking status, symptoms, and family history of concurrent colorectal cancer, number and location of polyps. Patients with SPS were matched to two cohorts (1) patients with SSA not meeting World Health Organization (WHO) criteria for SPS over 3 years; and (2) patients with exclusively adenomas. The control cases were also matched according to gender and endoscopist. Adenoma detection rates ranged from 25% to 40%.

RESULTS

Forty patients with SPS were identified and matched with 40 patients in each control group. In total 15452 colonoscopies were performed over the study period which amounts to a prevalence of 1: 384 patients (0.26%) with SPS. Fourteen patients (35%) required more than 1 year to accumulate enough polyps to reach WHO criteria for SPS. The diagnosis of SPS was largely incidental and 5% SPS patients were diagnosed with colorectal cancer over 3 years. The chance of detecting a meta-synchronous adenoma was similar in those with SPS (42%) and those with SSA (55%), P = 0.49. The majority of patients (75%) meeting criteria for SPS were women. The mean age of those with SPS (45 years) was significantly lower than both cohorts with SSA (57 years) and adenomas (63 years), P = 0.01. On univariate analysis cigarette exposure, first-degree family history of colorectal cancer and a high BMI weren’t significantly more associated with SPS compared to patients with SSA or patients with adenomas. However, patients with SPS (97%) and patients with SSAs not meeting SPS criteria (98%) were significantly more likely to be Caucasian compared to patients with adenomas (79%), P = 0.01.

CONCLUSION

The prevalence of SPS in our study was 0.26%. The vast majority of patients diagnosed with SPS were women. As a group, they were significantly younger compared to patients with SSA not meeting WHO criteria and patients with adenomatous polyps by more than a decade. Patients with SPS were no more likely to have a first degree relative with colorectal cancer or smoking history than the other two groups. Patients with serrated polyps were more likely to be Caucasian than patients with adenomas.

Keywords: Serrated lesions, Colonoscopy, Colorectal polyps, Polyposis syndrome, Colorectal cancer

Core tip: At the time of diagnosis, sessile serrated polyposis syndrome (SPS) is associated with a high risk of concurrent colorectal cancer. Early diagnosis of SPS is crucial and this case-control study aim to delineate differences in risk factors for SPS and other types of polyps. The vast majority of patients diagnosed with SPS in our study were women. They were younger and more likely to be Caucasian compared to patients with adenomatous and patients with serrated adenomas not meeting World Health Organization criteria. SPS patients were no more likely to have a family history of colorectal cancer or cigarette exposure than other polyp groups.