Appendix Removal Linked to Reduced Risk of Bacteria-Associated Colorectal Cancer

Researchers at Brigham and Women's Hospital have discovered a link between appendectomy (surgical removal of the appendix) and a reduced risk of a specific type of colorectal cancer characterized by the presence of the potentially tumor-promoting bacteria Fusobacterium nucleatum.

The study, published in Annals of Surgery, analyzed data from two large prospective cohort studies involving over 139,000 participants. The findings revealed that individuals who had undergone an appendectomy had a 47% lower risk of developing Fusobacterium nucleatum-positive colorectal cancer compared to those who had not undergone the procedure.

"We found that individuals who had undergone appendectomies had a significantly lower risk of acquiring this subtype of colorectal cancer," said senior author Shuji Ogino.

The appendix, once considered a redundant organ, has recently been shown to play a role in the immune system. However, the long-term effects of its removal on the gut microbiome and colorectal cancer risk have been unclear.

The research team aims to further investigate the impact of appendectomies on colorectal neoplasms containing other potentially pathogenic bacteria and explore the appendix's role in contributing bacteria to the gut microbiome and how its absence influences different aspects of human health.

While the study highlights the association between appendix removal and reduced risk of a specific type of colorectal cancer, the researchers caution against recommending preventive appendectomies. "We cannot definitively say whether removing an organ considered to be a potential 'safe house' for certain bacteria always affects colorectal cancer risk positively or negatively," said Ogino.

The study underscores the need for further research to understand the appendix's role in the body and the long-term impacts of its removal on overall health.