Flexible sigmoidoscopy successfully evaluates immunotherapy-mediated colitis
Click Here to Manage Email Alerts
LAS VEGAS – Flexible sigmoidoscopy with distal colon biopsies was an acceptable initial diagnostic test among patients with suspected immunotherapy-mediated colitis, according to a presentation at the ACG Annual Scientific Meeting.
“Over the years, immune checkpoint inhibitors (ICIs) have shown promise in treating a variety of cancers. With their increased use has come increased incidence of adverse effects, one of the most common being immunotherapy-mediated colitis or IMC. IMC symptoms are generally classified by National Cancer Institute Common Terminology Criteria for Adverse Events criteria as used in clinical trials, but these criteria are not associated with IMC severity or prognosis and are not clinically meaningful alone,” Sadie De Silva, MD, of UHS Southern California Medical Education Consortium, said. “Lower endoscopy with biopsy is the gold standard for diagnosing IMC, but the optimal strategy for obtaining biopsies and assessing severity remains unclear.”
In a cross-sectional, single-center study, researchers evaluated the clinical, endoscopic and histopathological features for 51 patients who underwent endoscopic evaluation for IMC. They further assessed the diagnostic yield of full colonoscopy (n = 47) or flexible sigmoidoscopy (n = 4) with systematic biopsies of the right, transverse and left colon.
While all flexible sigmoidoscopies demonstrated evidence of IMC in the left colon, full colonoscopy demonstrated evidence of IMC in either all segments of the colon simultaneously (35 participants) or absence from all segments (12 participants); researchers observed no cases of isolated proximal colonic biopsies demonstrating IMC or alternative structural causes for symptoms. Compared with endoscopically abnormal colon, abnormal mucosa had higher sensitivity for severe IMC in the right (52.4% vs. 37.9%), transverse (40.9% vs. 30%) and left (50% vs. 40%) segments. They noted endoscopically normal mucosa demonstrated histologic evidence of IMC up to 68.6% of the time.
“The clinical relevance of this is that we can use flexible sigmoidoscopy as an initial diagnostic study as we saw distal colon biopsies are sufficient in making that diagnosis,” De Silva concluded. “We do need further studies to investigate the role of lower endoscopy, particularly flexible sigmoidoscopy as a tool, not only for diagnosing but also evaluating severity and assessing treatment outcomes. Larger studies would be helpful, especially for more aggressive severe disease requiring biologic therapy, to better address this question.”
Collapse
De Silva S, et al. Abstract: Flexible sigmoidoscopy may be sufficient for initial evaluation of immunotherapy-mediated colitis. Presented at: ACG Annual Scientific Meeting; Oct. 22-27, 2021; Las Vegas (hybrid meeting).
Read more about
Click Here to Manage Email Alerts