Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2023 Aug;15(12):913-920.
doi: 10.2217/imt-2022-0245. Epub 2023 Jun 9.

Evaluation of appendectomy as a potential risk factor for immune checkpoint inhibitor-associated enterocolitis

Nira A Krasnow  1 , Donald F Chute  2 , Ayo S Falade  3 , Crystal M North  1   4 , Kerry L Reynolds  1   5 , Michael L Dougan  1   6
Affiliations

Evaluation of appendectomy as a potential risk factor for immune checkpoint inhibitor-associated enterocolitis

Nira A Krasnow et al. Immunotherapy. 2023 Aug.

Abstract

Aims: The relationship between appendectomy and immune checkpoint inhibitor (ICI) enterocolitis was explored. Methods: Patients who began ICIs between July 2010 and September 2020 (n = 10,907) were included. The exposure group included patients with evidence of appendectomy prior to ICIs in operative notes (n = 380). The control group included patients with evidence of normal appendix in radiologic reports (n = 3602). ICI enterocolitis was defined as histopathologic evidence of colitis or enteritis attributed to ICIs. The association between appendectomy and ICI enterocolitis was characterized by multivariate logistic regression. Results: 248 patients (6.2%) developed ICI enterocolitis. The odds of ICI enterocolitis were similar among those with prior appendectomy and those without appendectomy (adjusted odds ratio: 0.82; 95% CI: 0.49-1.36; p = 0.449). Conclusion: No association was found between prior appendectomy and ICI enterocolitis.

Keywords: appendectomy; immune checkpoint inhibitor enterocolitis; immune checkpoint inhibitors; immune-related adverse events.

Plain language summary

Immune checkpoint inhibitors (ICIs) are a form of cancer treatment that ‘unleash the brakes’ on the body's immune system. One common and sometimes serious side effect of this type of drug is gut inflammation. Studies have shown that appendectomy, or surgical removal of the appendix, lowers the risk of inflammatory bowel disease, which is another cause of gut inflammation. This research assessed whether appendectomy reduces the risk of gut inflammation caused by ICIs. Patients on ICIs for cancer with and without prior appendectomy were identified. The rates of gut inflammation caused by ICIs between these two groups were compared and the rates of this side effect were similar. This suggests that appendectomy does not reduce the risk of gut inflammation caused by ICIs.

PubMed Disclaimer

Conflict of interest statement

The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

Figures

Figure 1.
Figure 1.. Identification of appendectomy and normal appendix groups.
aEvidence of appendectomy was identified by querying operative notes for evidence of appendectomy using regular expression keyword search to identify segments of reports that indicated prior appendix removal or appendectomy. bFor the 10,510 patients without evidence of appendectomy in operative reports, radiologic reports were queried with text search using regular expression keywords to identify segments of reports that contained evidence for a normal appendix. Using this method, n = 3669 patients had explicit evidence of normal appendix. Of these patients, n = 3602 were confirmed to have a visualized appendix on subsequent manual review. cFor patients for whom appendectomy operation date was not available, date of earliest entry of appendectomy history in chart was used as evidence that operation occurred prior to ICI initiation. ICI: Immune checkpoint inhibitor; MGB: Mass General Brigham.
See this image and copyright information in PMC

References

    1. Bagchi S, Yuan R, Engleman EG. Immune checkpoint inhibitors for the treatment of cancer: clinical impact and mechanisms of response and resistance. Annu. Rev. Pathol. Mech. Dis. 16(1), 223–249 (2021). - PubMed

    2. • An informative recent review of immune checkpoint inhibitors (ICIs) in the treatment of cancer.

    1. Baumeister SH, Freeman GJ, Dranoff G, Sharpe AH. Coinhibitory pathways in immunotherapy for cancer. Annu. Rev. Immunol. 34(1), 539–573 (2016). - PubMed
    1. Ramos-Casals M, Brahmer JR, Callahan MK et al. Immune-related adverse events of checkpoint inhibitors. Nat. Rev. Dis. Primer 6(1), 38 (2020). www.nature.com/articles/s41572-020-0160-6 - PMC - PubMed

    2. • An excellent review of immune-related adverse events (irAEs).

    1. Pauken KE, Dougan M, Rose NR, Lichtman AH, Sharpe AH. Adverse events following cancer immunotherapy: obstacles and opportunities. Trends Immunol. 40(6), 511–523 (2019). - PMC - PubMed
    1. Xu C, Chen Y-P, Du X-J et al. Comparative safety of immune checkpoint inhibitors in cancer: systematic review and network meta-analysis. BMJ 363, k4226 (2018). - PMC - PubMed

    2. • This meta-analysis includes 36 different phase II and III randomized trials and provides general rates of irAEs with different ICI antibodies.

Publication types

Substances

LinkOut - more resources