Secondary Primary Cancer after Primary Gastric Cancer: Literature Review and Big Data Analysis Using the Health Insurance Review and Assessment Service (HIRA) Database of Republic of Korea.

Advances in cancer screening and early detection, as well as improvements in surgical techniques and therapeutics, have contributed to decreasing gastric cancer mortality. The number of gastric cancer survivors continues to rise; however, long-term follow-up has revealed an increase in the risk of post-gastrectomy symptoms or other health problems, such as extra-gastric secondary primary cancer (SPC), in these survivors. Therefore, evidence-based screening for new primary cancer is needed in these populations; however, the incidence of SPC varies by country or continent and its characteristics have not been clearly reported. The characteristics of SPC are of increasing interest to both treatment providers and gastric cancer survivors; thus, this literature review explores not only the epidemiology and biology of SPC but also clinical and biological factors that influence its prognosis.

[Air pollution and respiratory symptoms of school children in a panel study in Seoul].

OBJECTIVES: The aim of this study was to assess the effect of air pollution on the daily respiratory symptoms of elementary school children in Seoul. METHODS: Using the panel study design, we collected diary data for the children's respiratory symptoms during the 1st day approximately 15th day of April, July, October and December in 2003 among the 2nd and 3rd grade elementary school students. We merged the respiratory symptom data with the ambient air pollution data that was monitored by Ministry of Environment. Using a generalized estimate equation, we evaluated the relationship between the daily symptoms of the subjects and the exposure to air pollution after controlling for various potential confounders. RESULTS: The nitrogen dioxide (NO2) exposure of the current day significantly increased the upper respiratory symptoms (adjusted odds ratio=1.12, 95% CI=1.01-1.24) and the lower respiratory symptoms (adjusted odds ratio=1.18, 95% CI=1.06-1.31) in the elementary school children. The sulfur dioxide (SO2) and carbon monoxide (CO) exposure in the current day was associated with the lower respiratory symptoms (adjusted odds ratio=1.12, 95% CI=1.01-1.25 for SO2; adjusted odds ratio=1.16, 95% CI=1.02-1.32 for CO). CONCLUSIONS: We found that exposure to air pollution affects the daily respiratory symptoms in children. This study suggests that the effect on children's health? due to the short term changes in air pollution levels needs to be considered as an important public health problem.