Body Mass Index Impacts on Surgical Outcomes in Gastrointestinal Cancer

Body mass index (BMI), a simple ratio of weight to height, exerts a profound influence on the technical aspects, perioperative complications and long-term prognosis of gastrointestinal cancer surgery. Patients at the extremes of BMI present distinct challenges: underweight individuals often lack the nutritional reserve necessary for wound healing and immune competence, while overweight and obese patients may experience prolonged operative times, increased blood loss and limited lymph node retrieval. Beyond BMI, visceral fat area measured by computed tomography has emerged as a more precise predictor of postoperative infectious complications. Intriguingly, an “obesity paradox” is observed in gastric cancer, whereby moderately obese patients exhibit improved survival unless complicated by postoperative abdominal infections, which in turn drive peritoneal recurrence. Incorporation of BMI into multifactorial risk models alongside immune-nutritional markers such as the lymphocyte-to-monocyte ratio enhances the prediction of both short-term complications and disease-free survival. Preoperative optimisation programmes, including very low-calorie diets to reduce visceral adiposity without depleting muscle mass, are increasingly adopted to improve surgical access and accelerate recovery. A globally informed, patient-centred approach to BMI management underpins best practice in gastrectomy, colectomy and oesophagectomy.

Research from Nature Portfolio

Recent studies have demonstrated that in gastric cancer the presence of the obesity paradox hinges on the avoidance of postoperative abdominal infectious complications, which dramatically increase peritoneal recurrence in obese individuals. Machine-learning approaches applied to gastric cancer cohorts have identified BMI among the top predictors of postoperative recurrence, alongside operative time and age, underscoring its role in risk stratification. These analyses have informed the development of predictive algorithms with high accuracy and have highlighted BMI as a key variable in forecasting both early surgical complications and long-term outcomes.

Body Mass Index Impacts on Surgical Outcomes in Gastrointestinal Cancer publication trend

The graph below shows the total number of articles in body mass index impacts on surgical outcomes in gastrointestinal cancer across all publications each year (not limited to Nature Index journals).

Technical terms

Body Mass Index (BMI): A numerical value of a person’s weight in kilograms divided by the square of height in metres, used to classify underweight, normal weight, overweight and obesity.

Visceral Fat Area: The cross-sectional area of fat surrounding internal abdominal organs, typically measured by computed tomography, which correlates with metabolic risk and postoperative infections.

Obesity Paradox: The counterintuitive observation that overweight or mildly obese patients exhibit better survival in certain diseases, provided they avoid specific complications.

Neoadjuvant Immunochemotherapy: A preoperative treatment regimen combining immunotherapy and chemotherapy aimed at shrinking tumours and enhancing surgical outcomes.

References

1. A novel immune-nutritional score predicts response to neoadjuvant immunochemotherapy after minimally invasive esophagectomy for esophageal squamous cell carcinoma. Frontiers in Immunology (2023).
2. Obesity paradox as a new insight from postoperative complications in gastric cancer. Scientific Reports (2023).
3. A machine learning-based predictor for the identification of the recurrence of patients with gastric cancer after operation. Scientific Reports (2021).
4. Impact of visceral obesity on infectious complications after resection for colorectal cancer: a retrospective cohort study. Lipids in Health and Disease (2023).
5. Preoperative weight loss program involving a 20‐day very low‐calorie diet for obesity before laparoscopic gastrectomy for gastric cancer. Asian Journal of Endoscopic Surgery (2018).
6. Impact of body mass index on surgical outcomes of gastric cancer. BMC Cancer (2018).