Computed tomography colonography to assist with risk stratification

ABSTRACT

Background and Aim: In March 2020, the Gastroenterological Society of Australia released recommendations for endoscopic triaging during the coronavirus disease 2019 (COVID-19) pandemic. These unique circumstances resulted in diagnostic delays. In a Brisbane hospital, computed tomography (CT) colonography was used as a minimally invasive method to examine the colon, with the aim of identifying and expediting the diagnosis of patients with high-risk abnormalities. We aimed to explore the findings and outcomes of CT colonography. Methods: In April 2020, an experienced gastroenterologist reviewed and triaged about 645 category one waitlist colonoscopy patients. Of these, 130 patients were selected on clinical grounds and referred to three community radiology providers for CT colonography between April and June 2020. Data were retrospectively collected, including patient demographics, indication from referral source, and radiology reports. Colonoscopy reports were reviewed using ProVation software. Results: Of the 130 patients selected, 92 consented and 39 declined. After CTcolonography, 13 patients were referred for colonoscopy and 79 were referred to a gastroenterology outpatient clinic. The indication for referral addressed “red flag” symptoms of unexplained anemia, rectal bleeding, weight loss, or change in bowel habits in 54/92 patients (58.7%). The median time from referral to CT colonography was 20 days. Of the CT colonographies, 75 (81.5%) were recorded as being “good” or “satisfactory” quality. The significant colonic findings and outcomes of CT colonography are shown in Table 1. One patient had a significant extracolonic finding of a malignancy, consistent with renal cell carcinoma. This patient was reviewed in the urology outpatient clinic 9 days after CT colonography. Conclusion: This cohort of patients faced delays in the time to colonoscopy due to the COVID-19 pandemic. In using CT colonography, three patients were diagnosed with significant conditions that required urgent management and treatment. In 78/130 patients (60%), no high-risk radiological abnormalities were identified, and they were referred to an outpatient clinic. CTcolonography may be an appropriate tool to assist with risk stratification for patients facing long waitlists. This requires further study to assess outcomes after clinic consultation and colonoscopy procedures.