Sex Disparities In Cancer Incidence And Mortality By Period And Age In Jiashan County,China

Backgrounds and objectiveWith the change of people's behaviors,lifestyle factors and dietary structure,and the aging of the population,the incidence and mortality of cancer have been increasing rapidly.According to WHO International Agency for Research on Cancer(IARC),there were 14 million new incident cases and 8.2 million death cases in 2012,with 3.07 million new incidence cases and 2.2 million death cases in China.It's estimated that there would be 4.29 million new incident cases and 2.81 million death cases in 2015 in China.Cancer has become an important public health issue in China.It's reported that sex disparities exist in cancer incidence and mortality,which showed a male predominance.However,the relevant studies from China are very limited.In fact,the study of sex disparities in cancer incidence and mortality can provide clues for related cancer research.To analyze the distribution of incidence and mortality of all cancers and specific cancer types in males and females,and to explore the corresponding sex disparities in cancer incidence and mortality by period and age in Chinese population,a descriptive study was carried out based on the incident and death data of all cancer cases between 1990 and 2014,in Jiashan County,Zhejiang Province.Material and methodsAll data about incident and death cases of cancer diagnosed between Jan 1,1990 and Dec 31,2014 were extracted from the database of Cancer Registry in Jiashan County.Population data were obtained from public security bureau of Jiashan County.The data were used to calculate crude incidence(mortality)rate,age-standardized incidence rate(ASIR),age-standardized morality rate(ASMR),age-specific incidence(mortality)rate.The incidence rates and morality rates per 100,000 person for all cancers and each cancer type were calculated for the periods 1990 to 2014(total),1990 to 1999,2000 to 2009 and 2010 to 2014,in which sex stratified were also calculated.The 2010 China census population was used as standard population to calculate the ASIRs and ASMRs per 100,000 person for all cancers and each cancer type,in which sex stratified were also calculated.The age-specific incidence(mortality)rate per 100,000 person for all cancers and main cancer types were calculated,in which sex was also stratified.In addition,the corresponding male-to-female incidence rate ratios(IRRs)and morality rate ratios(MRRs)for specific cancer types were calculated,and 95%confidence intervals(95%CIs)for corresponding IRRs and MRRs were calculated as well.The differences in cancer incidence and mortality between males and females were compared by using u-test.Statistical analyses were all performed using SAS 9.4 for windows and Microsoft Office Excel 2007.The significance level was P<0.05.ResultsThe number of total new cancer incident cases were 25 998,with 15 609 for males and 10 389 for females,respectively.The number of total new cancer death cases were 18 446,with 12 266 for males and 6 180 for females,respectively.The crude incidence rate of all cancers was 276.01/105 for th.e whole period 1990 to 2014,with 331.68/105 for males and 220.43/105 for females,respectively.The male-to-female IRR for all cancers was 1.50(95%CI:1.47-1.54),and there existed significant difference between males and females(P<0.05).The ASIR of all cancers was 226.13/105,with 266.04/105 for males and 187.22/105 for females,respectively.The male-to-female IRR for all cancers was 1.42(95%CI:1.39-1.46),and there existed significant difference between males and females(P<0.05).The sex disparities in cancer incidence existed for the periods 1990 to 1999,2000 to 2009 and 2010 to 2014 as well.The cancer incidence rate increased dramatically after 40 years old and finally peaked at age group of 70+,with incidence rate of 1375.86/105.The largest differences in cancer incidence between males and females existed in age group of 80+,with IRR of 2.32.The crude morality rate of all cancers was 195.83/105 for the whole period 1990 to 2014,with 260.64/105 for males and 131.12/105 for females,respectively.The male-to-female MRR for all cancers was 1.99(95%Cl:1.93-2.05),and there existed significant difference between males and females(P<0.05).The ASMR of all cancers was 155.39/105,with 206.55/105 for males and 104.98/105 for females,respectively.The male-to-female MRR for all cancers was 1.97(95%Cl:1.91-2.03),and there existed significant difference between males and females(P<0.05).The sex disparities in cancer morality existed for the periods 1990 to 1999,2000 to 2009 and 2010 to 2014 as well.The cancer mortality rate increased dramatically after 40 years old and finally peaked at age group of 70+,with mortality rate of 1196.49/105.The largest differences in cancer mortality between males and females existed in age group of 80+,with MRR of 2.36.Among the main cancer types,only gallbladder cancer and thyroid cancer showed female predominance in incidence,with the corresponding IRRs of 0.55(95%CI:0.46-0.65)and 0.26(95%CI:0.21-0.30),and there existed significant differences between males and females(P<0.05).The remaining cancers all showed male predominance,and there existed significant differences between males and females(P<0.05)excluding brain and nervous system tumor and myeloma.Lung,bronchus and trachea cancer was the most common cancer,followed by colorectal cancer,liver cancer,stomach cancer,breast cancer,esophagus cancer,pancreas cancer,brain and other nervous system tumor,thyroid cancer,oral cavity and pharynx cancer.The 10 most common cancers accounted for 80.90%of all cancers.Among the main cancer types above,the cancer incidence rate peaked at age group of 70+ excluding gallbladder cancer and thyroid cancer.And males predominated in cancer incidence for a majority of age groups excluding gallbladder cancer and thyroid cancer.Among the main cancer types,only gallbladder cancer and thyroid cancer showed female predominance in mortality,with the corresponding MRRs of 0.57(95%CI:0.48-0.69)(P<0.05)and 0.70(95%CI:0.41-1.20).The remaining cancers all showed male predominance,and there existed significant differences between males and females(P<0.05).Lung,bronchus and trachea cancer was the leading cause of cancer deaths,followed by liver cancer,stomach cancer,colorectal cancer,esophagus cancer,pancreas cancer,brain and other nervous system tumor,gallbladder cancer,leukemia,oral cavity and pharynx cancer.The 10 of the leading cause of cancer death accounted for 86.55%of all cancer death.Among the main cancer types above,the cancer mortality rate peaked at age group of 70+ excluding oral cavity and pharynx cancer,and thyroid cancer.And males predominated in cancer mortality for a majority of age groups excluding gallbladder cancer and thyroid cancer.ConclusionThe study suggests that a male predominance in incidence and mortality for most of cancer types(excluding gallbladder and thyroid cancer)in Jiashan population.Futhermore,males predominate in cancer incidence and mortality for most of age groups while considering the specific ages.