Potential Association Observed Between Bariatric Surgery and Increase in Obesity-Related CRC Resections

SAN ANTONIO - A national analysis has revealed an increase in the rate of colorectal cancer resections occurring after bariatric surgery.

The observed increase was greatest among patients aged younger than 50 years, according to data presented Monday, October 28, 2019, at the 2019 Annual Scientific Meeting of the American College of Gastroenterology, in San Antonio, Tex.

Despite an overall decrease in the rate of colorectal cancer in the United States, data published earlier this year in Molecular Oncology showed the incidence in those under the age of 50 years has been increasing by 2% per year. At the same time, there is evidence in this younger population of an unexpected increase in long-term risk of colorectal cancer occurring after bariatric surgery. 

To examine this relationship further, Hisham Hussan, MD, assistant professor at The Ohio State University Wexner Medical Center, Columbus, Ohio, and colleagues looked at data from the 2006-2013 National Inpatient Sample (NIS) to identify patients who underwent surgical resection for an obesity-related gastrointestinal cancer. Specifically, the researchers were looking at patients who were morbidly obese (BMI ≥40 kg/m²; n=28 041) and those with prior bariatric surgery (n=2238).

From 2006 to 2013, the number of patients who were morbidly obese and had undergone bariatric surgery, who also underwent colorectal cancer resections increased concurrently across all age groups. The greatest increase occurred in patients aged younger than 50 years (P<.001).

In contrast, there was no observed rise in the occurrence of non-colorectal cancer obesity-related gastrointestinal cancer, ie, esophageal or gastric cancer, in relation to bariatric surgery.  According to the researchers, this suggests “a low probability of referral bias.”

Additionally, the number of non-bariatric surgery/non-obese patients with colorectal cancer resections decreased from 2006 to 2013 for patients both younger and older than age 50.

Based on these results, Hussan and colleagues suggested further research is warranted to elaborate on these trends and provide biological context for the results.

Source: Hussan H, Patel A, Porter K, Lieberman D, Ahnen D. Bariatric surgery is associated with a recent temporal increase in colorectal cancer resections, most pronounced in adults <50 years of age: a 2006-2013 national analysis. Poster P1675 presented at: ACG 2019 Annual Scientific Meeting; October 27, 2019; San Antonio, Tex.