Impact of Body Mass Index on Survival Depending on Sex in 14,688 Patients with Gastric Cancer in a Tertiary Hospital in South Korea

The incidence and prognosis of gastric cancer (GC) shows sex difference. This study aimed to evaluate the effect of body mass index (BMI) on GC survival depending on sex. The sex, age, location, histology, TNM stages, BMI, and survival were analyzed in GC patients from May 2003 to February 2020 at the Seoul National University Bundang Hospital. Among 14,688 patients, there were twice as many males (66.6%) as females (33.4%). However, under age 40 years, females (8.6%) were more prevalent than males (3.1%). Cardia GC in males showed a U-shaped distribution for underweight (9.6%), normal (6.4%), overweight (6.1%), obesity (5.6%), and severe obesity (9.3%) but not in females (p=0.003). Females showed decreased proportion of diffuse-type GC regarding BMI (underweight [59.9%], normal [56.8%], overweight [49.5%], obesity [44.8%], and severe obesity [41.7%]), but males did not (p