Decrease in the esophageal cancer incidence rate in mountainous but not level parts of Cixian County, China, over 29 years.

BACKGROUND: Cixian county has one of the highest incidence rates of esophageal cancer (EC) in China, as well as the world. In 1974, the Cixian population-based cancer registry system was established, so that there is now information on esophageal cancer cases over almost 30 years. METHODS: Data from Cixian Cancer Registry were checked and analyzed using SPSS 11.5. RESULTS: From 1974 to 2002, a total of 18,471 new esophageal cancer cases were registered in Cixian, 11,068 in males and 7,403 in females. The age standardized incidence rate (ASR) for males was 208.77 per 100,000, while for females it was 120.47 per 100,000. There was a clear trend for decrease overall in the incidence rate of esophageal cancer over the 29 years (X(2)=19.94, P<0.001). As to the geographic distribution, the incidence rate in mountainous and hilly areas showed a significant decline (X(2) = 195.00 and X(2) = 46.08, respectively, both P X(2)0.001). Data for esophageal cancer incidence in level land areas in contrast were relatively steadily, with increase in recent years. CONCLUSION: Esophageal cancer has decreased in Cixian county during the last 29 years, but this is due to change in mountainous and hilly areas. Compared to other regions in the world, Cixian county still has a very high incidence of ECs.

Mortality report of malignant tumors in SheXian, Hebei Province, China, from the 1970's to the present.

BACKGROUND: Investigations into mortality from malignant tumors were initiated in the 1970's in Hebei Province, China, and especially for esophageal cancer the rates were high, Shexian county ranking in first place of the towns that were surveyed. METHODS: Since the 1970's, a register system for all causes of death has been in place. Data for the decades of the 1970's, 1980's, 1990's and 2000's century were here checked and analyzed by SPSS software. RESULT: From the decades of the 1970's onward, the mortality rates of malignant tumors/100,000 were 272.0, 260.1, 211.7 and 180.1, respectively, with significant differences over time (x2 =240.5, P<0.001). The main malignant tumors were esophageal, gastric, liver, lung and cervix cancers. The sum of their percentages of all cancer deaths were 92.1% in the 1970's, 91.6% in the 1980's, 92.1% in the 1990's and 93.9% in the 21st century. The sex ratios (male vs female) were 1.5, 1.5, 1.7 and 2.0 respectively, with an ascending trend. Mortality rates of malignant tumors increased with age, with an obvious geographic distribution. The highest mortality of malignant tumors was evident in the area where the Qingzhang and Zhuozhang rivers join. CONCLUSION: From 1970's to the beginning of the 21st century, the mortality rate of malignant tumors has shown a declining trend. The main responsible cancers are in the esophagus, stomach, liver, and lung. Through great efforts for prevention, obvious decrease for esophageal cancer and cervix cancer has been achieved, but the mortality rate for gastric cancer remains high.