Abstract PO-183: Pre-diabetes, diabetes and the risk for adenoma detection
Authors: Joseph Dimitri F. , Li Ellen , Martello-Rooney Laura , Follen Michelle , Grossman Evan 
Published: December 2020

Background U.S Multi-Society Task Force of Colorectal Cancer (MSTF) has suggested that screening begin at a younger age in Blacks to detect precancerous adenomas. Our group conducted a multi-institution retrospective study of clinical data collected in 2012 to identify biological factors associated with adenoma detection. However, the results of the investigation revealed that the included Urban Safety Net Hospital (USNH) had a relatively lower adenoma detection rate (ADR) that may have confounded other analysis in the study. After successful initiatives to improve ADR, this interim study compares the incidence of adenomas in non-diabetic (ND), pre- diabetic (PD) and Type II diabetic (T2DM) categories. Methods This study is a retrospective analysis of prospectively collected data from January 2017 to June 2018. Chart review was used to build a registry of subjects within ages 45 - 75 years old that completed an initial screening colonoscopy. Subjects at high risk for adenoma or colorectal cancer (hereditary syndromes, inflammatory bowel disease), symptomatic presentation, poor bowel prep, or incomplete colonoscopy were excluded from the study. ND, PD and T2DM groups were established by clinical diagnosis or HgbA1c levels according to American Diabetes Association guidelines. 12 Subjects with an unknown diabetes status were also excluded from this analysis. Chi- square analysis was performed to determine significance at a threshold of p ≤ 0.05 for unadjusted p-values. Preliminary Results As shown in Table 1, 248 patients met the inclusion criteria. 94% of patients identified as Black or African American, &lt;1 % as Caucasian and 5% declined to identify with a race or was left unknown. 94 and 89 out of 248 subjects had pre-diabetes or diabetes, respectively. The overall adenoma detection rate is at 29%. The percentage of detected adenomas in the ND, PD and T2DM group were 22%, 33%, and 29% respectively. Discussion As evidence by an ADR of 29%, preliminary data from 2017 shows quality improvement in colonoscopies performed at this USNH. In this cohort that is 94% Black, the incidence of T2DM and PD is higher than the CDC’s national averages for individuals ≥ 45 years old. 62% of this population sample are diabetic or pre-diabetic. At a sample size of 284 subjects, this ongoing study is underpowered and cannot yet conclude an association between a diagnosis of PD, T2DM, and the incidence of adenomas.

However, there is a trend that shows that a higher proportion of adenomas are in the PD and the T2DM groups in comparison to the ND group. The relatively high proportion of adenomas in the PD group suggests that the associated risk for colorectal cancer may occur prior to diagnosis with T2DM.

Citation Format: Dimitri F. Joseph, Ellen Li, Laura Martello-Rooney, Michelle Follen, Evan Grossman. Pre-diabetes, diabetes and the risk for adenoma detection [abstract]. In: Proceedings of the AACR Virtual Conference: Thirteenth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2020 Oct 2-4. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(12 Suppl):Abstract nr PO-183.