79 New research has shed light on the elevated risk of developing desmoid tumours (DT) after specific surgical procedures for patients with familial adenomatous polyposis (FAP). The study, which looked at more than 850 patients from several European countries, found that these tumours were much more common after ileal pouch-anal anastomosis (IPAA) than after ileorectal anastomosis (IRA). The findings were published in the journal Clinical Gastroenterology and Hepatology. If left untreated, FAP, a hereditary condition that causes numerous polyps in the colon and rectum, frequently results in colorectal cancer. To mitigate this risk, patients typically undergo colectomy – surgical removal of part or all of the colon. This can either involve IPAA, where a pouch is created from the small intestine to maintain bowel function, or IRA, which leaves part of the rectum intact. The study followed 852 patients who had undergone one of these procedures between 1961 and 2020. Desmoid tumours, which are non-cancerous but can invade surrounding tissues and cause significant complications, were a key focus. The researchers aimed to determine whether the choice of surgical procedure impacted the likelihood of developing DT post-operatively. The results indicate that patients who underwent IPAA had a considerably higher risk of developing desmoid tumours than those who received IRA. DTs were diagnosed in 12% of IRA patients, compared to 20% of those who had undergone IPAA. This pattern persisted even when adjusting for potential confounding factors such as patient age, family history of DTs, and genetic mutations. Furthermore, the data showed that the risk of DT development was highest in the early years following surgery, with the majority of cases arising within five years. Notably, surgical approach – whether open or laparoscopic – did not appear to significantly influence DT risk. The findings highlight a critical decision point in the management of FAP. While IPAA may be necessary for patients with a high risk of rectal cancer, it comes with an increased likelihood of desmoid tumours, which are a leading cause of death in FAP patients. As a result, surgeons and patients may need to weigh the benefits of rectal cancer prevention against the risks of DT when choosing between IRA and IPAA. The researchers also pointed out that other factors could contribute to DT risk, including the presence of a genetic mutation at the 3′ end of the APC gene and a family history of DTs. However, abdominal surgery itself remains the only modifiable risk factor in reducing the likelihood of these tumours. This study underscores the importance of personalised treatment plans for FAP patients, factoring in individual risk profiles for both colorectal cancer and desmoid tumours. Surgeons may lean towards IRA in cases where rectal polyps can be safely managed through regular endoscopic surveillance. However, for patients with a high burden of rectal polyps, IPAA may still be the preferred option despite the increased DT risk.