Stomach Cancer Incidence, Mortality and Survival Rate in Korean Elderly Pharmacoepidemiologic Cohort (KEPEC) in 1994~1998

Choi, Nam Kyong; Youn, Kyung Eun; Heo, Dae Seuk; Lee, Seung Mi; Kim, Yooni; Park, Byung Joo

Abstract

PURPOSE
This study was conducted to estimate the incidence, mortality and survival rate of stomach cancer in elderly people in Korea. MATERIALS AND METHODS: The source population was a Korean Elderly Phamacoepidemiologic Cohort (KEPEC), who were 65 years of age or older and living in Busan metropolitan city and Gyeongsangnam province, Korea. A subcohort of 38, 443 persons without stomach cancer were identified before enrolling the KEPEC. The stomach cancer incidence cases were detected from three different sources, the medical claims database of the Korea Medical Insurance Corporation (KMIC), the Korea Central Cancer Registry (KCCR), and the Busan Cancer Registry (BCR). A hospital survey for abstracting the relevant information to confirm the final diagnosis of the potential cases from the medical claims database was conducted. A medical oncologist reviewed the data to confirm the final diagnoses and the date of onset. The mortality cases due to stomach cancer were detected from the mortality database at the National Statistical Office. The incidence rate, the survival rate and the mortality rate of stomach cancer and their 95% confidence intervals were estimated using SAS Windows ver. 8.1. RESULTS: There were 338 confirmed stomach cancer cases in the KEPEC between 1 January 1994 and 31 December 1998. The age-standardized incidence rate of stomach cancer in the Korean elderly population was estimated to be 351.4 per 100, 000 person-years in males and 122.6 per 100, 000 person-years in females. In addition, 272 stomach cancer death cases were detected in the KEPEC between 1 Jan. 1994 and 31 Dec. 1998. The age-standardized mortality rate of stomach cancer to the Korean elderly population was estimated to be 268.5 per 100, 000 person-years in males and 93.7 per 100, 000 person-years in females. The one-year survival rate was 62.1% in males and 63.0% in females, which was considered to be statistically similar. The three-year survival rate was 38.9% in males and 40.9% in females. The five-year survival rate was 34.8% in males and 34.7% in females. CONCLUSION: The age-standardized male stomach cancer incidence rate and mortality rate to the Korean population were approximately three times higher than in female. However, there was little significant difference between males and females in terms of the overall survival rates. These results may be useful for planning a health policy for preventing and managing stomach cancer in Korea.