Incidence and risk factors of immune checkpoint inhibitor-induced colitis in Korean patients with cancer.

BACKGROUND/AIMS: Immune checkpoint inhibitors (ICIs) are effective in treating cancer. However, various immune-related adverse events (irAEs) have become prevalent, with ICI-induced colitis being the most common gastrointestinal irAE. Thus, we aimed to investigate the incidence and risk factors of ICI-induced colitis in Korean patients with cancer.

METHODS

This retrospective study included patients treated with ICIs between October 2015 and June 2022 in two tertiary referral centers in Daegu, Korea. The incidence of ICI-induced colitis was determined using electronic medical records. Risk factors for ICI-induced colitis were identified using univariate and multivariate logistic regression analyses.

RESULTS

We included 1,478 patients with ICI-treated cancer. The incidence of ICI-induced colitis was 3.5% (n = 52/1,478). Multivariate logistic regression analysis showed that the combination of nivolumab and ipilimumab was a risk factor for ICI-induced colitis (p = 0.006; odds ratio, 9.768; 95% confidence interval, 1.93-49.30).

CONCLUSION

ICI-induced colitis had an incidence rate of 3.5% and was associated with the combination of nivolumab and ipilimumab. Most patients with ICI-induced colitis developed mild symptoms that improved with supportive care alone, making ICI therapy resumption possible.