Gastrectomy for Gastric Cancer Associated With Weight Loss, Diabetes Remission

By Lisa Rapaport

May 04, 2021

(Reuters Health) - Gastric cancer patients with diabetes who undergo conventional gastrectomy have an increased likelihood of diabetes remission with greater postoperative weight loss, independent of baseline weight, a recent study suggests.

Researchers examined data on 5,150 patients with diabetes who had gastrectomy for cancer between 2004 and 2014. Overall, 25% of patients experienced diabetes remission within three years of surgery, which researchers defined as either fasting glucose plasma (FGP) without diabetes medication of less than 126 mg/dL or less than 100 mg/dL.

After a median follow-up period of 4.4 years from initial diabetes remission, the incidence rate of diabetes relapse was 107.0 per 1,000 person-years, as defined by reinitiation of diabetes medication, researchers report in the Journal of the American College of Surgeons.

"Weight decrease after gastric cancer surgery improves the insulin sensitivity and secretion, which lead the patients into diabetes remission postoperatively," said senior study author Dr. Sungsoo Park of the Center for Obesity and Metabolic Diseases at Korea University Anam Hospital and the Korea University College of Medicine in Seoul.

"However, the durability of diabetes remission might be dominated by diabetes severity, which is represented by the variables like age, fasting glucose, and the number of diabetes medications," Dr. Park said by email.

The majority of patients in the study underwent subtotal gastrectomy (81.4%), while the remainder had total gastrectomy. Almost one in five (19.3%) had adjuvant chemotherapy after gastrectomy.

Diabetes remission rates were 32% with total gastrectomy and 24% with subtotal gastrectomy, the study found. Total gastrectomy was associated with a significantly higher likelihood of diabetes remission (odds ratio 1.68).

Among the subset of 2,997 patients with weight data for three years post-gastrectomy, researchers found that that patients who had a postoperative BMI decrease of at least 20% had a more than 3-fold greater likelihood of diabetes remission than patients who had a postoperative BMI decrease of no more than 5%.

One limitation of the study is that researchers were unable to account for all potential confounders, the study team notes. They also were not able to adjust for the severity of diabetes based on laboratory data such as oral glucose tolerance tests, serum insulin, C-peptide levels, and glycated hemoglobin levels.

However, gastric cancer patients with diabetes have previously been shown to experience dramatic changes in weight after total gastrectomy in particular that have resulted in improvements in overall health as well as diabetes, hypertension, and sleep apnea, said Dr. Vivian Strong, an attending surgeon at Memorial Sloan Kettering Cancer Center and associate dean at Weill Cornell Medical College of Cornell University in New York City.

"For many of these patients, effects have been long-standing," Dr. Strong, who wasn't involved in the study, said by email.

Even with total gastrectomy, however, many patients experience significant weight regain once they recover their ability to eat and maintain weight, typically one or two years postoperatively, Dr. Strong added.

"Findings such as those in this study can be very helpful to physicians by informing patients that dietary control and maintenance are crucial after the initial recovery period of gastrectomy and also suggest that we should consider recommending nutritional support services to patients who have recovered long-term after gastrectomy to help prevent recidivism of comorbidities such as diabetes," Dr. Strong said.

SOURCE: Journal of the American College of Surgeons, online April 5, 2021.