中国膀胱癌流行现状与趋势分析

目的分析2015年中国膀胱癌发病与死亡情况以及1998—2015年的时间变化趋势。方法收集整理全国501个登记处上报国家癌症中心的2015年肿瘤登记数据,经审核质控后统计膀胱癌性别、年龄别、地区别和合计粗发病率、粗死亡率、年龄标化率等指标,并汇总1998—2015年间中国肿瘤登记膀胱癌世标发病率和世标死亡率,采用对数线性模型拟合年度变化百分比(APC)或平均年度变化百分比(AAPC)。结果膀胱癌居中国恶性肿瘤发病谱第13位,粗发病率为5.80/10万,中标发病率为3.60/10万,世标发病率为3.57/10万;粗死亡率为2.37/10万,中标死亡率为1.31/10万,世标死亡率为1.32/10万。男性膀胱癌居恶性肿瘤发病谱第7位,发病率为女性的3.8倍,男性死亡率为女性的4.0倍。城市地区发病率为农村的1.4倍,西部地区发病率和中部地区相近,均低于东部地区,死亡率的地区分布特征与发病率相似。膀胱癌的年龄别发病率和死亡率分别在45岁和55岁组快速上升,在80~84岁组和85岁组到达高峰。时间趋势分析显示,中国膀胱癌发病率在2007年出现下降拐点,1998—2007年世标发病率呈上升趋势(APC=2.58,P<0.001),2007—2015年呈下降趋势(APC=-3.82,P<0.001)。膀胱癌世标死亡率呈持续下降趋势,速度有所减缓,1998—2003年和2003—2015年的年平均下降速度分别为3.65%(P=0.002)和1.42%(P<0.001)。结论膀胱癌是威胁中国居民健康的主要恶性肿瘤之一,存在明显的性别、地区和年龄流行差异。中国膀胱癌发病率和死亡率呈下降趋势,仍需进一步加强烟草控制,倡导中老年患者树立早诊早治意识。     

Trends in Incidence of Childhood Leukemia,Khon Kaen,Thailand, 1985-2002

Background: The Khon Kaen Cancer Registry (KKCR), providing both hospital and population-based ‍registration, was established in 1984 in the Faculty of Medicine, Khon Kaen University. Leukemia is the most ‍common cancer among Thai children in Thailand, including both curable and preventable types, but no assessment ‍of trends has hitherto been performed. Objective: To perform a statistical assessment of the incidence trend of ‍childhood leukemia in Khon Kaen, Thailand, between 1985 and 2002. Methods: Population-based cases of childhood ‍leukemia registered between 1985 and 2002 were retrieved from the KKCR and cases with an ICD-O diagnosis ‍(coding C42) in children under 15 were selected. Incidence trends were calculated using the Generalized Linear ‍Model method (GLM), which generates incidence-rate-based logarithms. Results: Of the 277 cases of leukemia, ‍boys were affected two times more frequently than girls and half of the cases were 0-4 years of age. Most diagnoses ‍were histologically- or cytologically-proven and the most common type (affecting two-thirds, 65.7%) was acute ‍lymphoblastic leukemia (ALL). The overall, age-standardized rate (ASR) for leukemia was 31.9 per million (95%CI: ‍28.1 to 35.7); 40.3 per million (95%CI: 34.2 to 46.4) in boys and 27.0 (95%CI: 21.8 to 32.2) in girls. Incidence has ‍been increasing by 2.4% per year in boys (95% CI: -0.5 to 5.3) and 4.1% per year in girls (95% CI: 1.1 to 7.2). ‍Conclusions: This incidence-rate-based logarithm indicates that childhood leukemia has been increasing, suggesting ‍further epidemiological research on causes and possible prevention is needed.     

2000—2015年中国肿瘤登记地区胃癌发病趋势及年龄变化

目的 了解中国胃癌发病趋势及年龄变化,为胃癌防控提供依据。方法 基于22个有连续数据的登记处,整理2000—2015年胃癌发病数据,利用Joinpoint软件进行发病趋势分析。分析2000—2015年平均发病年龄,2000及2015年标化年龄别发病构成,构建出生队列并计算1920—2015年出生人群发病率、年龄别发病率。结果 2000—2015年中国22个肿瘤登记地区胃癌标化发病率呈现下降趋势,平均每年下降3.0%(-3.5~-2.4%)。人群出现发病年龄后移趋势,人口结构标化后除农村地区外各人群发病年龄的后移趋势消失。农村地区发病年龄上升趋势明显,高年龄发病患者占比增加。结论 胃癌发病率出现下降趋势,平均发病年龄出现后移趋势。     

Worldwide trends in cervical cancer incidence: Impact of screening against changes in disease risk factors

BackgroundCervical cancer trends in a given country mainly depend on the existence of effective screening programmes and time changes in disease risk factors, notably exposure to human papillomavirus (HPV). Screening primarily influences variations by period of diagnosis, whereas changes in risk factors chiefly manifest themselves as variations in risk across successive birth cohorts of women.MethodsWe assessed trends in cervical cancer across 38 countries in five continents, age group 30–74 years, using age-standardised incidence rates (ASRs) and age-period-cohort (APC) models. Non-identifiability in APC models was circumvented by making assumptions based on a consistent relationship between age and cervical cancer incidence (i.e. approximately constant rates after age 45 years).FindingsASRs decreased in several countries, except in most of Eastern European populations, Thailand as well as Uganda, although the direction and magnitude of period and birth cohort effects varied substantially. Strong downward trends in cervical cancer risk by period were found in the highest-income countries, whereas no clear changes by period were found in lower-resourced settings. Successive generations of women born after 1940 or 1950 exhibited either an increase in risk of cervical cancer (in most European countries, Japan, China), no substantial changes (North America and Australia) or a decrease (Ecuador and India).InterpretationIn countries where effective screening has been in place for a long time the consequences of underlying increases in cohort-specific risk were largely avoided. In the absence of screening, cohort-led increases or, stable, cervical cancer ASRs were observed. Our study underscores the importance of strengthening screening efforts and augmenting existing cancer control efforts with HPV vaccination, notably in those countries where unfavourable cohort effects are continuing or emerging.FundingBill and Melinda Gates Foundation (BMGF).     

广州市越秀区恶性肿瘤发病率分析

目的： 为评价广州市越秀区开展社区恶性肿瘤健康教育和早发现、早诊断的干预效果提供基线资料。方法：建立肿瘤发病登记制度,从医院病案、基层居委报病和死亡统计收集肿瘤病例。结果：越秀区１９９６ ～１９９７ 年恶性肿瘤粗发病率为２３７－６６／ 十万（ 男２６９－１９ ,女２０５－４１） ,发病率随年龄增长上升,肺癌排第一位,肝癌、乳腺癌和肠癌其次。未见发病有明显的地区聚集性。结论：广州市越秀区有较高的恶性肿瘤发病率。与国内其它大城市相比,其中鼻咽癌发病率较高。     

Cancer Incidence Trends in Thailand , 1989-2000

Through 2004, five cancer registries in Thailand have collected data for more than ten years. Three-year cancerincidence in Thailand covering the years 1989-1997 has been regularly reported in three volumes of ‘Cancer inThailand’. Since the data for the last decade of the 20th century have been collected, the trends in incidence of somecancer sites were analyzed. Data sources were registry data from Chiang Mai, Lampang, Khon Kaen, Bangkok, andSongkhla, which are representative of the four major geographic regions of Thailand. The data drawn in 2002covered the years 1989 to 1997 for Bangkok, the other four registries drew data from 1989 to 2000. The populationdenominators were estimated from the two censuses in 1990 and 2000. Only cancers of the liver, lung, colon-rectum,female breast, uterine cervix, and all cancer sites were analyzed since cancers of these sites may have major publichealth impacts. Age-specific incidence rates of different 5-year age groups were projected through the period 2007-2009 using a linear regression model if the rates were increasing, and a log-linear model to prevent prediction of anegative rate if the rates were decreasing. During the past decade, colorectal and breast cancers showed a statisticalsignificant increasing trend, while the trend was generally stable for cancer of other sites. The number of new cancercases of all sites is expected to be approximately 125,000 by the year 2008, compared with 81,000 in 1999. However,the accuracy of projections depends very much on the quality of the cancer registries’ data. The Bangkok registrysignificantly improved case ascertainment in recent years, while the Chiang Mai registry had a consistent drop inincidence of cancer at many sites. In-depth investigation of some cancer sites and age period cohort modeling arerequired for better understanding of cancer trends in Thailand.     

2016年上海市子宫颈癌发病和死亡情况与2002—2016年的变化趋势分析

背景与目的：上海市疾病预防控制中心每年更新上海市恶性肿瘤发病和死亡及其趋势的统计资料。本文分析2016年上海市子宫颈癌发病和死亡的基本情况及其2002—2016年的变化趋势。方法：采用上海市疾病预防控制中心建立的人群基础肿瘤登记管理系统和死因登记系统收集的2002—2016年子宫颈癌发病和死亡资料,按诊断或死亡年份、年龄组分层分析,计算数量、构成比、粗率、年龄别率、年龄标准化率（标化率）等指标,分析子宫颈癌发病和死亡各个维度的数量和率值趋势,标化率应用Joinpoint回归模型计算年度变化百分比分析变化趋势。计算不同诊断年份组合的新发病例的部分诊断特征指标的数量和构成比。应用Segi’s 1960年世界标准人口构成计算标化率。 结果：2016年上海市子宫颈癌新发病例和死亡人数分别为987例和267人,粗发病率为13.53/10万,标化发病率为8.26/10万,粗死亡率为3.66/10万,标化死亡率为1.87/10万。年龄别发病的数量和率值分别在55 ~ 59岁组和45 ~ 49岁组达到高峰。年龄别死亡的数量和率值分别在50 ~ 54岁组和80 ~ 84岁组达到高峰。上海市子宫颈癌的标化发病率在2002—2010年以年均12.51%的增速上升,在2010—2016年则以年均3.12%的增速上升。2002—2016年的标化死亡率以年均4.52%的增速上升。子宫颈癌的病理组织学类型以鳞癌为主,病理学诊断比例和诊断时Ⅰ期比例持续增长。结论：上海市子宫颈癌发病和死亡处于全球较低流行水平,但均在增长,现况和趋势反映了上海户籍人口在相关危险因素、筛查和检测技术应用和诊疗水平发展等方面的变化。加强相关监测和研究有助于调整防治措施,减少负担。     

云南省肿瘤登记地区2011—2015年宫颈癌发病和死亡特征及时间趋势

目的 了解云南省肿瘤登记地区2011—2015年宫颈癌的发病和死亡特征及时间趋势,为开展宫颈癌防治提供参考.方法 收集整理2011—2015年云南省肿瘤登记地区宫颈癌(ICD-10编码为C53)的发病死亡病例.分城乡统计宫颈癌的发病率、死亡率、标化发病率、标化死亡率、截缩率、累积率(0～74岁)、趋势变化年度百分比(A...     

Incidence and mortality of gynaecological cancers: Secular trends in urban Shanghai,China over 40 years

AimAppraisal of cancer trends is essential for future cancer control, but relevant studies in China are scarce due to a lack of long-term data. With 40-years of cancer registry data, we sought to evaluate secular time trends in incidence and mortality of gynaecological cancers in an urban Chinese population.Materials and methodsData on incidence and mortality of invasive cervical, uterine and ovarian cancer were collected by the Shanghai Cancer Registry. Age-standardised incidence and mortality rates were calculated for women aged 20–84 in urban Shanghai between 1973 and 2012. Age-period-cohort Poisson regression models were used to evaluate age, period and cohort effects. Overall linear trends, interpreted as the estimated annual percentage change (EAPC), were derived from the net drift in age-drift models.ResultsOverall, cervical cancer incidence and mortality substantially decreased (EAPC = −4.5% and −5.5%, respectively); however, an upward trend was apparent among younger women (age <60). Uterine cancer incidence increased slightly (EAPC = 1.8%), while mortality decreased over time (EAPC = −2.4%). Ovarian cancer incidence and mortality both increased, although the increase in incidence (EAPC = 1.8%) was larger than mortality (EAPC = 0.6%). While cohort effects were most evident for cervical cancer incidence and mortality, significant age, period, and cohort effects were found for all three gynaecological cancers evaluated.ConclusionsThese secular trends in incidence and mortality of gynaecological cancers in Shanghai likely reflect changing risk factor profiles and improved cancer prognosis over time, and suggest new priorities and call for additional efforts for gynaecological cancer prevention and control for women in China.     

2012—2016年河北省肿瘤登记地区肝癌发病和死亡流行情况分析

目的 分析河北省肝癌的发病和死亡状况及其趋势变化,为制订肝癌防治策略提供科学依据.方法 收集河北省2012—2016年27个肿瘤登记地区的肝癌发病和死亡数据,按城乡(城市/农村)、性别和年龄组分析肝癌发病率和死亡率.应用2000年中国人口普查和Segi's世界人口计算年龄标准化率.采用Joinpoint模型对磁县和涉县...     

Increasing incidence of childhood leukemia in Northwest Italy, 1975-98

Although some childhood cancer registries reported increasing incidence, the evidence and magnitude of time trends in the incidence of childhood leukemia are debated and the scientific evidence is conflicting. Only limited data have so far been supplied from Southern European countries. We present an analysis of the incidence trend of childhood leukemia in Piedmont (NW Italy) in 1975-98, based on data from the population-based childhood cancer registry. The Childhood Cancer Registry of Piedmont has been recording cases of childhood neoplasms since 1967. Procedures have been uniform and are based on an active search for cases and relevant information. Only cases with confirmed residence in Piedmont at diagnosis are included. Eight hundred cases of leukemia (622 acute lymphoblastic [ALL], 133 acute nonlymphoblastic [AnLL], 45 other and unspecified) were recorded in the period 1975-98 considered in our study. Incidence trends were analyzed using piecewise regression and Poisson regression, based on annual incidence rates. As results from the 2 analyses were similar, only the former were reported. In the age group 1-4 years, a statistically significant annual 2.6% increase in incidence rate of ALL (adjusted by age and gender; 95% confidence interval [CI] 1.13-4.13) was estimated. There was no evidence of increase in other age groups. During 1980-98, a statistically significant 4.4% annual increase (95% CI 1.86-6.90) was seen for pre-B-All in the age group 1-4 years. An increase was also seen for T-ALL that was not statistically significant. Sensitivity analyses were conducted, with no relevant differences from the main results. Our data suggest an increasing trend in ALL incidence for children between the ages of 1 and 4 years. These results are unlikely to be explained by changes in quality of data or exhaustiveness in reporting in the study period. The results were not changed in the sensitivity analyses we conducted. Possible causes to be investigated include environmental factors, changes in family size and parental age, socioeconomic conditions and geographical distribution of cases.     

Cervix Cancer in Khon Kaen,Northeast Thailand, 1985-1999

The incidence of cancer of the cervix uteri in Khon Kaen Province is moderately high (age-standardised rate 16.8 ‍per 100 000 person-years), with about a two-fold variation in incidence between different districts. Stage at presentation ‍is considerably more advanced than in the United States and Europe, and there has been little change in incidence ‍over the last 15 years. Currently, control of cervix cancer is through early detection and treatment. Screening ‍programmes have, to date, been opportunistic, but a new national plan anticipates that all women will be screened ‍six times during their lifetime. The results from Khon Kaen provide a benchmark against which the success of this ‍policy can be evaluated.     

Trends in cancer incidence in Kyadondo County, Uganda, 1960-1997

Incidence rates of different cancers have been calculated for the population of Kyadondo County (Kampala, Uganda) for four time periods (1960-1966; 1967-1971; 1991-1994; 1995-1997), spanning 38 years in total. The period coincides with marked social and lifestyle changes and with the emergence of the AIDS epidemic. Most cancers have increased in incidence over time, the only exceptions being cancers of the bladder and penis. Apart from these, the most common cancers in the early years were cervix, oesophagus and liver; all three have remained common, with the first two showing quite marked increases in incidence, as have cancers of the breast and prostate. These changes have been overshadowed by the dramatic effects of the AIDS epidemic, with Kaposi's sarcoma emerging as the most common cancer in both sexes in the 1990s, and a large increase in incidence of squamous cell cancers of the conjunctiva. In the most recent period, there also seems to have been an increase in the incidence of non-Hodgkin lymphomas. So far, lung cancer remains rare. Cancer control in Uganda, as elsewhere in sub-Saharan Africa, faces a threefold challenge. With little improvement in the incidence of cancers associated with infection and poverty (liver, cervix, oesophagus), it must face the burden of AIDS-associated cancers, while coping with the emergence of cancers associated with Westernization of lifestyles (large bowel, breast and prostate).     

No further increase in the incidence of esophageal adenocarcinoma in Sweden

Since 1970, the incidence of esophageal adenocarcinoma has increased rapidly in Western populations, whereas the incidences of gastric cardia and gastric non-cardia adenocarcinoma have increased moderately and declined, respectively. The Swedish Cancer Register and Total Population Register provided opportunities for a valid update of incidence trends of these tumors including the year 2008. Joinpoint regression was used to assess any shifts in trends with calendar time. The esophageal adenocarcinoma incidence reached a peak in 2005, and then showed a decrease. During the period 2001-2008, the joinpoint regression analysis indicates a virtually stable incidence (annual percentage increase 1.1, 95% confidence interval [CI] -2.7 to 5.1). The cardia adenocarcinoma incidence has slightly decreased after 1990 (annual percentage decrease -1.0, 95% CI -1.6 to -0.3). The decreasing incidence of gastric non-cardia adenocarcinoma has continued steadily during recent years (annual percentage decrease -4.9 (95% CI -5.2 to -4.7). Thus, an encouraging break in the rising incidence of esophageal adenocarcinoma has been seen in Sweden since 2005, whereas the corresponding incidences of gastric cardia and non-cardia adenocarcinoma have been stable and decreasing, respectively.     

2016年广西肿瘤登记地区恶性肿瘤发病和死亡分析

目的 分析2016年广西肿瘤登记地区恶性肿瘤发病和死亡情况。 方法 对2016年广西31个肿瘤登记处的肿瘤登记数据进行分析,按城乡、性别、年龄别对数据进行分层,分别计算恶性肿瘤发病和死亡的粗率、标化率、累积率（0～74岁）和前10位恶性肿瘤构成。人口标准化率采用2000年全国普查标准人口年龄构成和Segi's 世界标准人口年龄构成计算。 结果 纳入分析的31个登记处共覆盖人口11 628 368人（其中城市6 698 487人,农村4 929 881人）,恶性肿瘤新发病例28 140例,发病粗率、中标率、世标率和累积率（0～74岁）分别为241.99/10万、196.89/10万、192.26/10万、21.90%;无论是中标率还是世标率,男性均高于女性,城市地区均高于农村地区。恶性肿瘤发病在40岁以后快速上升,在80岁年龄组时达到高峰。发病前10位恶性肿瘤依次为肝癌、肺癌、乳腺癌、结直肠癌、宫颈癌、胃癌、鼻咽癌、前列腺癌、子宫肿瘤和脑瘤,占全部恶性肿瘤发病的75.65%。恶性肿瘤死亡病例17 647例,死亡粗率、中标率、世标率和累积率（0～74岁）分别为151.76/10万、119.05/10万、117.31/10万、13.27%;无论中标率还是世标率,男性均高于女性,城市地区均低于农村地区。恶性肿瘤死亡在40岁以后快速上升,在85岁年龄组时达到高峰。死亡前10位恶性肿瘤依次为肝癌、肺癌、结直肠癌、胃癌、乳腺癌、鼻咽癌、宫颈癌、食管癌、前列腺癌和白血病,占全部恶性肿瘤死亡的81.74%。结论  2016年广西肿瘤登记地区恶性肿瘤发病率和死亡率略高于2015年,肝癌、肺癌、结直肠癌、乳腺癌和鼻咽癌是重点防控的癌种。     

上海市区女性生殖系统恶性肿瘤发病趋势分析

目的对1972～1999年上海市区常见的女性生殖系统恶性肿瘤的发病率进行统计,分析其发病趋势及变化原因,为防治措施的制定提供依据.方法根据上海市肿瘤发病登记处收集的1972～1999年的上海市区卵巢癌、宫颈癌、宫体癌和不明部位子宫癌的病例资料和相应年份的人口资料,分别计算各年龄组的年龄别发病率.并采用直接法计算世界人口标化发病率,对数线性回归法计算标化率的年变化率(Annual percentage change,APC),并对病例数进行加权计算.结果1972～1999年上海市肿瘤登记处共登记卵巢癌6106例、宫颈癌8063例,宫体癌3 933例和不明部位子宫癌1 312例.28年来,宫体癌和卵巢癌的标化发病率呈上升趋势,分别从1972～1974年的2.49/10万和4.77/10万上升至1996～1999年的4.75/10万和6.88/10万,年增长率分别为3.0%和2.0%.同期宫颈癌的标化发病率从26.66/10万快速下降至2.18/10万,年下降率达10.5%.不明部位子宫癌的标化发病率亦呈下降趋势(P＜0.01).宫体癌以55～64和65～74岁组发病率上升最快,年增长率分别为2.5%和3.3%.卵巢癌各年龄组的发病率均有上升趋势,年变化率都在1.0%以上.宫颈癌发病率下降最快的年龄组是45～54和55～64岁组,25～34和35～44岁组的发病率在近几年有升高趋势.结论上述肿瘤的发病率及年龄别发病率的变化趋势提示,上海女性生活方式和环境因素的改变可能是导致这种变化的重要原因.     

Trends in Incidences of Stomach and Colorectal Cancer in Khon Kaen,Thailand 1985-2004

Background: The life styles of Thai people are changing with westernization and this would be expected to havean impact on the prevalence of cancer and other non-communicable diseases. For planning control programmes it isnecessary to monitor change over time and the present study was conducted to provide information on stomach andcolorectal cancer incidence rates in Khon Kaen Cancer Registry (KKCR), established in 1984 at the Faculty ofMedicine, Srinagarind Hospital, Khon Kaen University. Objective: To assess trends in urban and rural areas ofKhon Kaen province during 1985 - 2004. Methods: Data for stomach and colorectal cancer with an ICD-O diagnosis(coding C16 , C18 – C20) from the population-based cases of the KKCR, registered between 1985 and 2004, wereretrieved and incidence trends were calculated using the Generalized Linear Model method (GLM), which generatesincidence-rate-based logarithms. Results: The study population comprised 2,530 cases, 721 of stomach (males 449,females 272) and 1809 of colorectal (males 976, females 833) cancer. Most cases were aged 35-75 years. Accordingto the histopathological diagnosis, the most common was adenocarcinoma with over 90 percent. The overall agestandardizedincidence rates (ASR) for stomach cancer were 4.5 and 1.4 per 100 000 in males and females, respectively,during 1985-1989, 3.7 and 2.0 during 1990-1994, 3.0 and 2.2 during 1995-1999 and 3.6 and 1.8 during 2000-2004 .The respective figures for colorectal cancer were 3.3 and 2.6, 4.6 and 3.1, 5.4 and 3.5 and finally 5.8 and 5.3. In bothurban and rural areas males were affected more frequently than females, although a shift was evident towardsdecrease in the se ratio was evident for colorectal cancers over time. Discussion: The results of this study showedslight increase in the incidence of colorectal cancer in Khon Kaen province, while rates for stomach cancer remainedquite stable. The findings indicate a need for continuing research in stomach and colorectal cancer epidemiology,with subdivision into particular sites within these two sections of the gut.     

Cancer incidence in the Hmong of Central California, United States, 1987-94

The Hmong are an ethnic minority in China, some of whom migrated tothe mountainous areas of North Vietnam, Laos, and Thailand in the 19th and20th centuries. Because of their support for the United States during theVietnam war, many Laotian Hmong fled to Thailand and eventually werere-settled in the US after the end of that conflict. Approximately100,000Hmong currently live in the US, of whom about half reside in theCentral Valley of California. The purpose of this study was to measure cancerincidence in this unique new immigrant population. Using the resources of theCancer Registry of Central California (CRCC), a population-based cancerregistry, cancer incidence in the Hmong was evaluated by calculatingage-adjusted incidence rates as well as by calculating proportional incidenceratios. Compared with all races combined, elevated rates of cancer in theHmong were observed for the following sites: nasopharynx, stomach, liver,pancreas, leukemia, and non-Hodgkins lympho ma. Cervical cancer incidenceoverall was elevated, but more noteworthy, invasive cervix cancer rates weremuch higher than expected. Lower cancer rates were found for breast,prostate, and colorectal cancer. Hmong also experienced advanced stage andgrade of disease at diagnosis for many cancer sites in addition to cervicalcancer, which may be explained by cultural factors, including avoidance ofWestern medical care and low rates of participation in screening programs.This population should be followed closely and monitored for patterns ofcancer incidence in the future since it provides a natural laboratory forstudies of cancer etiology as this population gradually becomes acculturatedto the Western lifestyle.     

Increasing thyroid cancer incidence in Canada, 1970-1996: time trends and age-period-cohort effects.

We examined time trends in thyroid cancer incidence in Canada by age, time period and birth cohort between 1970 and 1996. Age-specific incidence rates by time period and birth cohort were calculated and age-period-cohort modelling used to estimate effects underlying the observed trends. Overall age-adjusted incidence rates of thyroid cancer doubled, from 3.3 and 1.1 per 100 000 in 1970-72 to 6.8 and 2.2 per 100 000 in 1994-96, among females and males respectively. Almost all the increase between 1970-72 and 1994-96 was due to papillary carcinoma of the thyroid. Age, birth cohort and period effects significantly improved the fit of the model for females, while age and birth cohort effects were significant determinants of the incidence among males. There were significant differences in the patterns/curvature for age, period and birth cohort effects between women and men. Our results suggest that the increases in thyroid cancer incidence in Canada may be associated with more intensive diagnostic activities and change in radiation exposure in childhood and adolescence. Temporal changes in reproductive factors among young women may explain some of the gender differences observed.     

Trends in Incidence of Childhood Lymphoma in Khon Kaen,Thailand, 1985-2008

Background: Lymphoma is the second most common of childhood cancer in Thailand, but data on trendsover time are limited. Objective: To perform a statistic assessment of the incidence trend of childhood lymphomain Khon Kaen, Thailand, between 1985 and 2008. Method: All children aged < 15 years newly diagnosed withlymphoma according to International Childhood Cancer Classification (ICCC) during January 1, 1985- December31, 2008 were collected from data base of Khon Kaen Provincial Registry. Aged-adjusted incidence rates (ASRs)were calculated by standard method and trends were calculated using the generalized linear model method, which utilizes incidence-rate-base logarithms. Results: During 1985-2008 there were 72 children (47boys and 25 girls) who were diagnosed with lymphoma in Khon Kaen province. The peak age-group of diseasewas in the 5-9 year olds for both sexes. All cases were pathologically proven. Non-Hodgkin lymphoma (NHL)was more common than Hodgkin disease (ratio 7:1). The overall ASR was 6.04 per million (95%CI: 4.64 to 7.45)and the ASR was 7.64 per million (95%CI: 5.44 to 9.84) in boys and 4.37 per million (95%CI: 2.64 to 6.10) ingirls. Significant increases were observed for boys, since the 2006 to 2008 ASR was 15.3 per million (95%CI:5.73 to 25.0). Trend analyses during 1985 - 2008 showed that incidence among boys for lymphoma increasedby 1.38 percent per year (95%CI:- 4.6-8.3) while the incidence among girl decreased by 2.6 percent per year(95%CI:- 12-6.8). Conclusions: Our data showed that the incidence of childhood lymphoma in Khon Kaenprovince was similar to the one of Thailand but lower than those of western countries. During the past 24 years,the incidence trend seems to be increasing in boys but decreasing in girls. Interpretation is difficult without abetter understanding of what underlies the reported changes.