WASHINGTON, D.C. / RankWire.AI / – According to recent research, patients who had their appendix removed due to acute appendicitis experienced fewer subsequent diagnoses of colorectal cancer compared to those treated solely with antibiotics. This retrospective analysis utilized data from a substantial global health database. Researchers observed a colorectal cancer rate of 0.7% among patients who underwent an appendectomy, whereas the rate was 1.7% in the antibiotic-only group. This difference indicates a 58% lower relative risk associated with surgery.
Data was obtained through the TriNetX Global Collaborative Network, encompassing information from 168 healthcare organizations. Researchers identified individuals with acute appendicitis who received either surgical or antibiotic treatment. After matching patients based on relevant factors, each group initially included 15,774 participants. The final sample comprised 15,616 patients who had an appendectomy and 15,295 who received only antibiotics, after excluding those with prior colorectal cancer diagnoses. The records revealed 110 cases of colorectal cancer following appendectomy and 254 cases after antibiotic treatment.
The findings were presented at the American College of Surgeons Clinical Congress 2026, held in Washington from September 26 to September 29. The research abstract was reviewed and selected by the Scientific Forum program committee. However, the study has yet to undergo peer review by a medical journal, which limits the strength of the conclusions. While the research shows an association between treatment type and later colorectal cancer diagnosis, it does not prove that appendectomy prevents the disease.
Comparison of Surgical and Antibiotic Approaches
Acute appendicitis involves inflammation of the appendix, a small organ near the junction of the small and large intestines. Traditionally, treatment often involves surgical removal, known as an appendectomy. Recently, antibiotics have also become an accepted option for selected patients. Valentine Nfonsam, senior author and a professor and executive vice chair of surgery at Morehouse School of Medicine, emphasized that antibiotic therapy remains an important choice despite the study’s findings.
The study also explored factors influencing colorectal cancer development after appendicitis treatment. Sometimes, an undiagnosed colorectal tumor may cause appendicitis, especially if a tumor on the right side of the colon obstructs the appendix, leading to inflammation. Surgery allows for tissue examination post-removal, which can detect abnormalities and prompt further diagnostic tests not typically performed with antibiotics alone.
Findings Do Not Confirm Cancer Prevention
The appendix plays a role in immune function, containing lymphoid tissue, and is linked to the gut microbiome, comprising bacteria and microorganisms in the digestive system. The current research did not clarify whether these biological functions explain the variation in colorectal cancer diagnoses or whether inflammation or microbial shifts caused the observed association. Consequently, researchers refrain from suggesting that appendectomy can be considered a method of cancer prevention.
Previous studies have yielded mixed results regarding the relationship between appendectomy and colorectal cancer. A 2024 prospective analysis tracked over 224,000 participants across three large cohorts for up to 32 years, finding no evidence that appendectomy increases long-term colorectal cancer risk or precancerous conditions. This new research addresses a different question by comparing patients with appendicitis treated surgically to those receiving antibiotics alone. Researchers note that age, family history, and genetics remain key factors in assessing colorectal cancer risk.