Risk of colorectal cancer after appendectomy: A systematic review and meta‐analysis

Abstract

Background and Aim Appendectomy is associated with various diseases, but whether it increases the risk of colorectal cancer (CRC) remains uncertain. We conducted a systematic review and meta‐analysis aimed at investigating the suggested correlation between appendectomy and CRC. Methods Systematic retrieval was performed using the PubMed, Embase, Cochrane library, Web of Science, and http://ClinicalTrials.gov databases up to May 4, 2022, for studies reported the influence of appendectomy on CRC, colon cancer (CC) or rectal cancer (RC). Odd ratios (ORs) and 95% confidence intervals (CIs) of CRC after appendectomy were pooled using the random effects model. Subgroup analyses were carried on by region, sex, and tumor location. Results Our search identified 1743 articles, of which 22 studies from three continents published between 1964 and 2022 were eligible for inclusion. Overall, people with appendectomy had a higher risk of CRC (OR = 1.31; 95% CI [1.05, 1.62]). But the risk for Europeans was not significant (OR = 0.94; 95% CI [0.87, 1.02]; I2 = 0%), while for Americans and Asians, appendectomy would increase the risk of CRC (OR = 1.68; 95% CI [1.15, 2.44]; I2 = 65% and OR = 1.46; 95% CI [1.04, 2.05]; I2 = 98%), especially in females and in developing countries. It is worth noting that appendectomy might be a protective factor for CC in European women (OR = 0.87; 95% CI [0.77, 0.98]; I2 = 0%). Conclusions Appendectomy may be a risk factor for CRC, with varying degrees in different populations. More high‐quality cross‐regional studies are needed for better clinical decision making.

Beyond a vestigial organ: effects of the appendix on gut microbiome and colorectal cancer

“…A recent systematic review and meta‐analysis performed by Liu et al 15 . described findings similar to the trends described above, finding an overall OR of 1.31; 1.05–1.62 for CRC in the combined post‐appendectomy populations.…”

“…A recent systematic review and meta-analysis performed by Liu et al 15 described findings similar to the trends described above, finding an overall OR of 1.31; 1.05-1.62 for CRC in the combined post-appendectomy populations. They further conducted a subgroup analysis based on geographical populations and concluded that the trend toward increased OR for CRC post-appendectomy was significant in American and Asian populations (OR 1.68; 1.15-2.44 and OR 1.46; 1.04-2.05, respectively), but not significant in European populations (OR 0.94; 0.87-1.02).…”

Epidemiological insights into colorectal cancer in northwestern Algeria

“…Several studies have investigated the relationship between appendectomy and CRC risk, with some showing an increased risk of CRC after appendectomy, while others have either found no association or a potential protective effect. In a meta-analysis, individuals who had experienced an appendectomy had an elevated risk of CRC, implying a possible link with CRC development [ 7 ]. Conversely, a 14 years of follow-up large retrospective cohort study found that appendectomy patients had a 1.14 times higher risk of developing CRC than the general population [ 37 ].…”

Meta-Analysis and Systematic Review of the Role of Appendectomy in the Pathogenesis of Colorectal Cancer

“…Considering the appendix's role in immune functions, it is essential to evaluate whether its presence or absence is linked to the development of other diseases, including colorectal cancer, inflammatory diseases, and infections [5]. The outcomes of previous studies in this area have been inconsistent [6][7][8][9][10][11]. Consequently, a comprehensive review study is needed to amalgamate these findings.…”