Low-Energy Diet Before Colorectal Cancer Surgery Found Feasible and Safe: JAMA

A new study published in the Journal of American Medical Association showed that although recruiting issues still exist, replacing a low-energy total diet prior to colorectal cancer surgery proved practical, well tolerated, safe, and probably cost-effective.

Preoperative weight loss is becoming more popular as a way to improve surgical preparedness and lower complications in patients with colorectal cancer who are overweight. Prior to surgery, improving nutritional status and lowering metabolic stress may promote better postoperative results, speed up recovery, and offer an economical method of perioperative care. Thus, this study evaluated the viability of a preoperative weight loss strategy.

Between March 27, 2023, and August 13, 2024, persons with a body mass index of 28 or above who were awaiting curative elective colon cancer resection at eight hospitals around England participated in the assessor-blinded randomized clinical trial CARE, which included a 30-day postoperative follow-up. Between the decision to treat and surgery, the intervention comprised dietetic assistance with a low-energy (800 kcal/d, 76 g/d of protein) whole food replacement program.

Recruitment (≥72 patients), engagement (≥75% of dietetic telephone conversations attended), adherence (≥60% of intervention participants achieving ≥5% weight reduction), and retention (≥85%) were the primary outcome advancement requirements for a final study. Morbidity, symptoms, and changes in weight and fat-free mass were secondary outcomes. Cohort simulation was used to estimate outcomes across a 30-year time horizon.

36 of the 71 randomly assigned surgical patients (mean age 64 years, mean BMI 35.4) received the intervention, whereas 35 received standard care. The hiring process went a little more slowly than anticipated. 85% of dietetic calls were attended, indicating a high level of intervention adherence.

Prior to surgery, the intervention group dropped 4.3 kg more on average, with 61% of patients losing at least 5% of their body weight compared to 9% of participants receiving normal care. The groups' increases in fat-free mass were comparable. Although fecal incontinence and irritated skin improved better in the intervention group, the incidence of complications were similar. Retention was full, there were no significant side effects, and the intervention seemed to be economical.

Overall, as part of prehabilitation prior to colon cancer surgery, an intensive preoperative weight reduction strategy proved safe, practical, and probably cost-effective, with evidence of improvements in important symptoms. Before a final trial evaluates perioperative and long-term results, some recruiting issues must be resolved.

Reference:

Koutoukidis, D. A., Jebb, S. A., Reynolds, S., Hill, T. M., Foster, C., Horne, A., Wheatstone, P., Wright, M.-M., Dissanayake, H., Snowball, J., Challand, C., Fearnhead, N., Dennis, R., Thompson, B., Wilkin, R., Tou, S., Hassan, S., Foster, J., Penna, M., … Buczacki, S. J. A. (2025). Preoperative weight loss in patients with excess weight and colorectal cancer: The CARE feasibility randomized clinical trial: The CARE feasibility randomized clinical trial. JAMA Network Open, 8(12), e2547126. https://doi.org/10.1001/jamanetworkopen.2025.47126