P2222 - Endoscopic Yield and Its Predictive Factors in Abnormal Imaging of Lower Gastrointestinal Tract

Sanjeevani Kumar Tomar, MD¹, Sultan Mahmood, MD², Mitchell J. Eyerman, MD³, Anthony R. Khoury, DO¹, Brian M. Quigley, PhD⁴, Muhammad Tahir, MD^2
1University at Buffalo, Buffalo, NY; ²University at Buffalo Gastroenterology, Buffalo, NY; ³University Hospitals Case Medical Center, Case Western Reserve University, Cleveland, OH; ⁴Jacobs School of Medicine and Biomedical Sciences, Buffalo, NY

Introduction: The literature on endoscopic yield and its predictors in patients with abnormal abdominal imaging is heterogeneous. The present study aimed to evaluate the yield rates in endoscopies performed after abnormal imaging findings and identify the determinants that may predict increased yield.

Methods: This single-center retrospective study, conducted over a one-year period at a tertiary care center, included 121 patients, 46 males (38%) and 75 females (62%) of median age 61, who underwent endoscopy after abnormal imaging findings. Independent sample t-tests and ANOVAs were used to assess differences in yield between the presence or absence of symptoms and imaging modalities. Malignancy rates were examined by imaging modality and imaging findings with independent t-tests examining differences among individual pairs. Effect sizes (Cohen's d) and 95% confidence intervals were calculated for all comparisons.

Results: Abnormal abdominal imaging findings corresponded with abnormal endoscopy findings in only 44.6% of cases (Figure 1a). The endoscopic yield was significantly higher for patients with symptoms at any time before endoscopy (49% vs. 23.8%, p = .035) (Figure 1b), and especially when symptoms were present at the time of endoscopy (55% vs. 24.4%, p = .001) (Figure 1c). Magnetic resonance imaging (MRI) showed a significantly greater yield for malignant outcomes compared to computed tomography (CT) (50% vs. 10%, p = .003) (Figure 1d). There were also significant differences in malignancy detection rates based on imaging findings (Table 1). A finding of mass was not significantly more likely to detect malignancy than a finding of stricture (p = .931) but did show significantly greater detection of malignancy than wall thickening (p = .015). A finding of stricture was not significantly more likely to detect malignancy than a finding of wall thickening (p = .152) but, effect sizes suggest that differences may have emerged with larger sample sizes.

Discussion: Abnormal imaging findings require correlation with clinical symptoms before proceeding with endoscopy. MRI is a more reliable imaging modality than CT for malignancy detection. A stricture was not more likely to detect malignancy than wall thickening; however, the limited sample sizes preclude a definitive conclusion. Inflammatory changes and obstruction findings did not have any correlation with malignant outcomes. Findings of mass or stricture noted on any imaging modality warrant early endoscopic evaluation.


Figure: Figure 1
a: Abnormal abdominal imaging findings corresponded with abnormal endoscopy findings in only 44.6% of cases.
b: Endoscopy Yield Rate According to Absence/Presence of Symptoms at Any Time Before Endoscopy
c: Endoscopy Yield Rate According to Absence/Presence of Symptoms at Time of Endoscopy
d: Malignancy Detection Rates According to Imaging Modality

Imaging Findings	n	Malignancy Detection Rate
Inflammatory Changes	21	0.0%
Mass	26	30.7%
Obstruction	5	0.0%
Wall Thickening	39	7.7%
Stricture	3	33.3%
Fluid Collection	1	100%
Other Abnormal*	26	3.8%

Table: Table 1: Malignancy Detection Rates According to Imaging Findings
*Includes patients with unknown abnormal imaging findings as imaging was done at an outside facility.



Disclosures:
Sanjeevani Kumar Tomar indicated no relevant financial relationships.
Sultan Mahmood indicated no relevant financial relationships.
Mitchell Eyerman indicated no relevant financial relationships.
Anthony Khoury indicated no relevant financial relationships.
Brian Quigley indicated no relevant financial relationships.
Muhammad Tahir indicated no relevant financial relationships.


Sanjeevani Kumar Tomar, MD¹, Sultan Mahmood, MD², Mitchell J. Eyerman, MD³, Anthony R. Khoury, DO¹, Brian M. Quigley, PhD⁴, Muhammad Tahir, MD². P2222 - Endoscopic Yield and Its Predictive Factors in Abnormal Imaging of Lower Gastrointestinal Tract, ACG 2021 Annual Scientific Meeting Abstracts. Las Vegas, Nevada: American College of Gastroenterology.