Background: Noncardia gastric adenocarcinoma is not frequently mentioned in the United States. However, it is unclear if the previously reported decline in noncardia gastric adenocarcinoma has continued, and if detection and management has affected overall survival outside the setting of clinical trials.
Methods: We used the Surveillance, Epidemiology, and End Results registry (SEER) to identify all cases of noncardia gastric adenocarcinoma diagnosed between 1973 and 2002. The yearly age-adjusted incidence rates and the relative survival rates were calculated. Cox proportional hazards (PH) models were used to examine temporal trends from 1983 to 2003.
Results: Between 1973 and 2002, there were 24,103 cases of noncardia gastric adenocarcinoma. The age-adjusted yearly incidence rate declined by 23% between 1973 and 2002 from 4.3 to 3.3 per 100,000 person-years. However, the incidence of localized noncardia gastric adenocarcinoma (invasive neoplasm confined to the organ of origin) remained without change between 0.9 and 1.0 per 100,000 person-years, and increased with age, especially in the 85+ yr age group (a 47% increase between 1973 and 2002). The incidence rates in men were double those in women, and 1.6-fold and 2.6-fold higher in blacks and other races (mostly Asians), respectively, compared with whites. Patients with radiation and chemotherapy after gastrectomy had a 22% better mortality risk compared with those treated with gastrectomy alone. The Cox PH analysis shows no significant change in mortality risk related to year of diagnosis between 1983 and 2002, both in unadjusted as well as adjusted analyses. However, there were significant independent regional and racial variations in survival. Asians had a 17% lower mortality risk compared with whites.
Conclusions: Despite the overall decline in noncardia gastric adenocarcinoma, the incidence of local stage disease has remained stable in most ages and even increased in old ages. Unfortunately, there has been no significant improvement in survival during the past 20 yr. Moreover, there remain considerable regional as well as racial variations in mortality.