Detection of early gastric cancer: misunderstanding the role of mass screening

Background The proportion of early gastric cancer (EGC) increased from 15% during the 1960s to 50% recently, leading to a remarkable improvement of the 5-year survival rate of gastric cancer patients from 40% to 70%. This has been attributed to mass screening together with extended lymphadenectomy. However, more and more patients with EGC are diagnosed outside of mass screening. The aim of this study was to determine whether patients are symptomatic at the time of early detection and the method of tumor detection. Methods From 2001 to 2003, a total of 1226 patients (male/female 2.2 : 1.0, age 26–95 years) with EGC were treated at the National Cancer Center Hospital, Tokyo. We reviewed their medical records. Results Of these 1226 patients, 512 (41.8%) were symptomatic, and 714 (58.2%) reported no symptoms. Among the symptomatic patients, 468 (91.4%) were examined at outpatient clinics, 39 (7.6%) by private health assessment clinics, and 5 (1.0%) by mass screening. In total, 91.6% of the symptomatic patients directly underwent esophagogastro-duodenoscopy (EGD). Of the asymptomatic patients, 320 (44.8%) were examined at outpatient clinics, 306 (42.9%) by private health assessment clinics, and 88 (12.3%) by mass screening. EGD was the initial assessment in 67.8% and radiography in 32.2% of asymptomatic patients. Conclusion Most patients with EGC were detected outside of mass screening. This suggests that the Japanese public and physicians are well aware of the risk of gastric cancer and the importance of early detection. The effect of mass screening is misunderstood.