Demographic and lifestyle factors and survival among patients with esophageal and gastric cancer: The Biobank Japan Project

Background: Several studies have evaluated associations between the characteristics of patients with esophageal and gastric cancer and survival, but these associations remain unclear. We described the distribution of demographic and lifestyle factors among patients with esophageal and gastric cancer in Japan, and investigated their potential effects on survival. Methods: Between 2003 and 2007, 24- to 95-year-old Japanese patients with esophageal and gastric cancer were enrolled in the BioBank Japan Project. The analysis included 365 patients with esophageal squamous cell carcinoma (ESCC) and 1574 patients with gastric cancer. Hazard ratios (HRs) and 95% confidence intervals (CIs) for mortality were estimated using medical institution-stratified Cox proportional hazards models. Results: During follow-up, 213 patients with ESCC (median follow-up, 4.4 years) and 603 patients with gastric cancer (median follow-up, 6.1 years) died. Among patients with ESCC, the mortality risk was higher in ever drinkers versus never drinkers (multivariable HR = 2.37, 95% CI: 1.24, 4.53). Among patients with gastric cancer, the mortality risk was higher in underweight patients versus patients of normal weight (multivariable HR = 1.66, 95% CI: 1.34, 2.05). Compared to patients with gastric cancer with no physical exercise habit, those who exercised ≥ 3 times/week had a lower mortality risk (multivariate HR = 0.75, 95% CI = 0.61, 0.93). However, lack of stage in many cases was a limitation. Conclusions: Among patients with ESCC, alcohol drinkers have a poor prognosis. Patients with gastric cancer who are underweight also have a poor prognosis, whereas patients with physical exercise habits have a good prognosis.