W Ye1, W H Chow, J Lagergren, L Yin, O Nyrén. 1. Department of Medical Epidemiology, Karolinska Institutet, Box 281, SE171 77, Stockholm, Sweden. Weimin.Ye@mep.ki.se
Abstract
BACKGROUND & AIMS: Gastroesophageal reflux has been proposed as an important risk factor for esophageal and gastric cardia adenocarcinoma, but prospective data are lacking. Furthermore, the effect of antireflux surgery has not yet been studied. We conducted a population-based retrospective cohort study to fill these gaps. METHODS: A cohort of 35,274 male and 31,691 female patients with a discharge diagnosis of gastroesophageal reflux diseases, and another cohort of 6406 male and 4671 female patients who underwent antireflux surgery, were identified in the Swedish Inpatient Register. Follow-up was attained through record linkage with several nationwide registers. Standardized incidence ratio (SIR) was used to estimate relative risk of upper gastrointestinal cancers, using the general Swedish population as reference. RESULTS: After exclusion of the first year follow-up, 37 esophageal and 36 gastric cardia adenocarcinomas were observed among male patients who did not have surgery (SIR, 6.3, 95% confidence interval [CI], 4.5-8.7; SIR, 2.4, 95% CI, 1.7-3.3, respectively). SIR for esophageal adenocarcinoma increased with follow-up time (P = 0.03 for trend). Among male patients who had undergone antireflux surgeries, risks were also elevated (16 esophageal adenocarcinoma, SIR, 14.1, 95% CI, 8.0-22.8; 15 gastric cardia adenocarcinomas, SIR, 5.3, 95% CI, 3.0-8.7) and remained elevated with time after surgery. The cancer risk pattern in women was similar to that for men, but the number of cases were much smaller. CONCLUSIONS: Gastroesophageal reflux is strongly associated with the risk of esophageal adenocarcinoma, and to a lesser extent, with gastric cardia adenocarcinoma. The risk of developing adenocarcinomas of the esophagus and gastric cardia remains increased after antireflux surgery.
BACKGROUND & AIMS: Gastroesophageal reflux has been proposed as an important risk factor for esophageal and gastric cardia adenocarcinoma, but prospective data are lacking. Furthermore, the effect of antireflux surgery has not yet been studied. We conducted a population-based retrospective cohort study to fill these gaps. METHODS: A cohort of 35,274 male and 31,691 female patients with a discharge diagnosis of gastroesophageal reflux diseases, and another cohort of 6406 male and 4671 female patients who underwent antireflux surgery, were identified in the Swedish Inpatient Register. Follow-up was attained through record linkage with several nationwide registers. Standardized incidence ratio (SIR) was used to estimate relative risk of upper gastrointestinal cancers, using the general Swedish population as reference. RESULTS: After exclusion of the first year follow-up, 37 esophageal and 36 gastric cardia adenocarcinomas were observed among male patients who did not have surgery (SIR, 6.3, 95% confidence interval [CI], 4.5-8.7; SIR, 2.4, 95% CI, 1.7-3.3, respectively). SIR for esophageal adenocarcinoma increased with follow-up time (P = 0.03 for trend). Among male patients who had undergone antireflux surgeries, risks were also elevated (16 esophageal adenocarcinoma, SIR, 14.1, 95% CI, 8.0-22.8; 15 gastric cardia adenocarcinomas, SIR, 5.3, 95% CI, 3.0-8.7) and remained elevated with time after surgery. The cancer risk pattern in women was similar to that for men, but the number of cases were much smaller. CONCLUSIONS: Gastroesophageal reflux is strongly associated with the risk of esophageal adenocarcinoma, and to a lesser extent, with gastric cardia adenocarcinoma. The risk of developing adenocarcinomas of the esophagus and gastric cardia remains increased after antireflux surgery.