Published online Oct 21, 2022. doi: 10.3748/wjg.v28.i39.5750
Peer-review started: July 2, 2022
First decision: August 1, 2022
Revised: September 24, 2022
Accepted: October 10, 2022
Article in press: October 10, 2022
Published online: October 21, 2022
Immune checkpoint inhibitor-mediated colitis (IMC) is a common immune-related side effect (irAE) of checkpoint inhibitor treatment for cancer. Prior work has suggested that IMC may be associated with increased survival from cancer.
We sought to determine if IMC was associated with increased overall survival (OS) in a cohort of patients at our institution. These findings could expand existing data on IMC and cancer outcomes and might suggest a common immunological underpinning between the efficacy of checkpoint inhibitors and certain irAEs.
We performed a retrospective case-control study of individuals treated with immune checkpoint inhibitors at our institution who developed IMC, closely matched to a cohort of patients treated with checkpoint inhibitors without IMC. Using univariate and multivariate logistic regression, we determined significant clinical predictors of IMC and the association of presence of IMC on OS.
We found that IMC was significantly associated with a higher OS as well as OS greater than 12 mo. In contrast to previous findings, vitamin D supplementation was significantly associated with development of both IMC and severe IMC. However, prior treatment with immune-enhancing medications was significantly associated with decreased risk of IMC.
In multivariate logistic regression analysis, IMC was significantly associated with a higher OS but not PFS. IMC was significantly associated with OS greater than 12 mo. Vitamin D supplementation was associated with increased risk of IMC.
Our findings lend strength to the idea that IMC is associated with improved cancer outcomes with checkpoint inhibitor treatment. This may suggest common immunologic underpinnings between IMC and the anti-tumor effects of checkpoint inhibitors. These results also emphasize the importance of involving gastroenterologists with the management of IMC.
Future research in this area should seek to expand current knowledge of the relationship between IMC and cancer survival. In particular, future work should focus on broadening the type and number of patients treated with immune checkpoint inhibitors and on tracking patients prior to initiating checkpoint inhibitors to determine if this relationship remains significant prospectively.