A Model Approach to Calculate Cancer Prevalence from 5 Years Survival Data for Selected Cancer Sites in India – Part II

Objective: Prevalence is a statistic of primary interest in public health. In the absence of good follow-upfacilities, it is often difficult to assess the complete prevalence of cancer for a given registry area. An attemptis made to arrive at the complete prevalence including limited duration prevalence with respect of selectedsites of cancer for India by fitting appropriate models to 1, 3 and 5 year cancer survival data available forselected registries of India. Methodology: Cancer survival data, available for the registries of Bhopal, Chennai,Karunagappally, and Mumbai was pooled to generate survival for the selected cancer sites. With the availabledata on survival for 1, 3 and 5 years, a model was fitted and the survival curve was extended beyond 5 years (upto 30 years) for each of the selected sites. This helped in generation of survival proportions by single year andthereby survival of cancer cases. With the help of estimated survived cases available year wise and the incidence,the prevalence figures were arrived for selected cancer sites and for selected periods. In our previous paper, wehave dealt with the cancer sites of breast, cervix, ovary, lung, stomach and mouth (Takiar and Jayant, 2013).Results: The prevalence to incidence ratio (PI ratio) was calculated for 30 years duration for all the selectedcancer sites using the model approach showing that from the knowledge of incidence and P/I ratio, the prevalencecan be calculated. The validity of the approach was shown in our previous paper (Takiar and Jayant, 2013). TheP/I ratios for the cancer sites of lip, tongue, oral cavity, hypopharynx, oesophagus, larynx, nhl, colon, prostate,lymphoid leukemia, myeloid leukemia were observed to be 10.26, 4.15, 5.89, 2.81, 1.87, 5.43, 5.48, 5.24, 4.61,3.42 and 2.65, respectively. Conclusion: Cancer prevalence can be readily estimated with use of survival andincidence data.     

Contrasts in cancer prevalence in Connecticut,Iowa, and Utah

BACKGROUND: Cancer prevalence--the proportion of a population with cancer, including those recently diagnosed, those in treatment, and survivors--is an important indicator of future health care requirements. Only limited information on cancer prevalence is available for the United States. In particular, comparative interstate studies are not available. In this study, we estimate and analyze the prevalence of seven major cancers in Connecticut, lowa, and Utah using the tried and tested PREVAL method applied to National Cancer Institute registry data. METHODS: We analyzed data on 242,851 carcinomas of the stomach, colorectum, pancreas, breast, uterus (corpus), ovary, and non-Hodgkin lymphoma (NHL), diagnosed in white Americans from 1973 through 1992. Observed prevalence was estimated by applying the PREVAL method to incidence and life status data from the cancer registries. Complete prevalence was estimated by applying correction factors obtained by modeling incidence and survival rates. RESULTS: The ratio of the highest to the lowest prevalence (as proportions) ranged from 1.69 for uterine carcinoma to 2.73 for stomach carcinoma, showing that marked differences in cancer prevalence exist within the United States. Utah had the lowest prevalence for each carcinoma. Connecticut and lowa had similar prevalence levels for carcinomas of the colorectum, pancreas, and ovary and for NHL. Breast carcinoma was the most prevalent, with 826 cases per 100,000 of population in Utah, 1518 per 100,000 in lowa, and 1619 per 100,000 in Connecticut. Cancer survival did not differ greatly among the three registry populations. The major determinants of prevalence differences were incidence and the population age distribution. CONCLUSIONS: PREVAL provides reliable estimates of the numbers of living people in a population who have had a cancer diagnosis. Prevalence depends on incidence and survival and on the age structure of population. All these factors have changed markedly in recent years and will continue to do so in the future. Cancer prevalence should be monitored over time to evaluate changes by area, sex, age, and cancer site. The prevalence figures presented are directly comparable with those from European cancer registries.     

Cancer prevalence in the UK: results from the EUROPREVAL study.

BACKGROUND: Cancer incidence, mortality and survival statistics for the UK are routinely available; however, data on prevalence, which is generally regarded as an important measure for health planning and resource allocation, are relatively scarce. MATERIALS AND METHODS: Eight cancer registries in the UK, covering more than half the population, provided data based on >1.5 million cases of cancer. Total prevalence was calculated using methods developed for the EUROPREVAL study, based on modelling incidence and survival trends. The prevalence of cancers of the stomach, colon, rectum, lung, breast (in females), cervix uteri, corpus uteri and prostate, melanoma of skin, Hodgkin's disease, leukaemia and all malignant neoplasms combined, was estimated for the UK for the end of 1992. RESULTS: Overall, approximately 1.5% of males and 2.5% of females in the UK population at the end of 1992 were living with a diagnosis of cancer. These proportions increased steeply with age, with approximately 7.5% (7.3% and 7.8%, in males and females, respectively) of people aged > or =65 years living with a diagnosis of cancer. Of the individual cancers, by far the highest prevalence (almost 1%) was seen for breast cancer in females; more than one in three of all living female cancer patients had been diagnosed with breast cancer. For males, around half of prevalent cases had been diagnosed >5 years previously and 30% >10 years previously; for females, these figures were both higher, at approximately 60% and 40%, respectively. CONCLUSIONS: The estimates of prevalence presented here comprise: recently diagnosed patients in need of treatment and monitoring; long-term survivors, some of whom will nevertheless eventually die from the cancer, while others may be cured of the disease; and patients in the terminal phase who are dying from the cancer. Further work should attempt to identify the proportions of patients in the different phases of care in order to optimise the use of prevalence estimates in health care planning.     

Changes in the Distribution of Cancer Incidence in Nepal from 2003 to 2013

Background: Cancer incidence data are vital for cancer control planning in any nation. This retrospective study was conducted to compare the cancer incidence of all sites between the first cancer registry report and the most recent example in Nepal. Material and Methods: The cases in the first (2003) and latest (2013) national cancer registry reports, accumulated by all the hospital based cancer registries in Nepal were taken for the research. The frequencies, crude incidences and age specific incidences (per 100,000) of the five major cancers were calculated for both males and females. Result: The most common cancer type for males in both years 2003 and 2013 was lung. Stomach was the third most common cancer in 2003 while it was the second in 2013. Similarly, the first four major cancers (cervix, breast, lung and ovary) did not change between 2003 and 2013 in females. The total cancer incidence rate increased from 12.8 in 2003 to 30.4 per 100,000 in 2013 for males and from 15.1 to 33.3 in females. Conclusion: The most common cancers in males in 2003 and 2013 were in the bronchus and lung. Similarly, the most common cancer in females was cervix at both time points. The cancer incidence rate in females was higher than in males both in 2003 and 2013.     

Cancer Incidences in Rural Delhi - 2004-05

There are no data available on cancer incidence pattern in rural Delhi. This is the first report on cancerincidence among Delhi Rural population during 2004-05 which gives the first hand information on cancerincidence. The data for this report has been collected by Delhi Population based cancer registry. The sources forcancer registration are more than 162 Government Hospitals/centers and 250 private hospitals and nursinghomes. A total of 594 cancer cases with 317 males and 277 females were registered during the period 1st January2004 to 31st December 2005. The age adjusted (world population) incidence rates for all sites were 55.2 per100,000 for males and 47.7 per 100,000 for females. The leading sites of cancer among Delhi Rural males wasoral cavity (ASR: 8.0 per 100000) followed by lung (ASR: 6.5), larynx (ASR: 4.0) and bladder (ASR: 4.1). Infemales cervix uteri (ASR: 10.3 per 100,000) was the most common site of cancer followed by breast (ASR: 7.8),gallbladder (ASR: 3.5) and ovary (ASR: 3.3). The overall incidence rates of cancer in Delhi Rural werecomparatively very less than Delhi Urban. A statistically significant difference was also found between DelhiRural and Delhi Urban in incidence rates (ASR) for first four common sites. The rates in Delhi Rural are alsocomparatively lower than other rural registries situated in India.     

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.     

Projection of Cancer Incident Cases for India -Till 2026

Projection of cancer incidence is essential for planning cancer control actions, health care and allocationof resources. Here we project the cancer burden at the National and State level to understand the magnitudeof cancer problem for the various calendar years from 2011 to 2026 at 5-yearly intervals. The age, sex andsite-wise cancer incidence data along with populations covered by the registries were obtained from the reportof National Cancer Registry Programme published by Indian Council of Medical Research for the period2001-2004. Pooled age sex specific cancer incidence rates were obtained by taking weighted averages of theseseventeen registries with respective registry populations as weights. The pooled incidence rates were assumedto represent the country’s incidence rates. Populations of the country according to age and sex exposed to therisk of development of cancer in different calendar years were obtained from the report of Registrar Generalof India providing population projections for the country for the years from 2001 to 2026. Population forecastswere combined with the pooled incidence rates to estimate the projected number of cancer cases by age, sexand site of cancer at various 5-yearly periods Viz. 2011, 2016, 2021 and 2026. The projections were carried outfor the various leading sites as well as for ‘all sites’ of cancer. In India, in 2011, nearly 1,193,000 new cancercases were estimated; a higher load among females (603,500) than males (589,800) was noted. It is estimatedthat the total number of new cases in males will increased from 0.589 million in 2011 to 0.934 million by theyear 2026. In females the new cases of cancer increased from 0.603 to 0.935 million. Three top most occurringcancers namely those of tobacco related cancers in both sexes, breast and cervical cancers in women accountfor over 50 to 60 percent of all cancers. When adjustments for increasing tobacco habits and increasing trendsin many cancers are made, the estimates may further increase. The leading sites of cancers in males are lung,oesophagus, larynx, mouth, tongue and in females breast and cervix uteri. The main factors contributing to highburden of cancer over the years are increase in the population size as well as increase in proportion of elderlypopulation, urbanization, and globalization. The cancer incidence results show an urgent need for strengtheningand augmenting the existing diagnostic/tr eatment facilities, which are inadequate even to tackle the present load.     

Malignant Neoplasm Burden in Nepal - Data from the Seven Major Cancer Service Hospitals for 2012

In Nepal, while no population based cancer registry program exists to assess the incidence, prevalence, morbidity and mortality of cancer, at the national level a number of hospital based cancer registries are cooperating to provide relevant data. Seven major cancer diagnosis and treatment hospitals are involved, including the BP Koirala Memorial Cancer hospital, supported by WHO-Nepal since 2003. The present retrospective analysis of cancer patients of all age groups was conducted to assess the frequencies of different types of cancer presenting from January 1st to December 31st 2012. A total of 7,212 cancer cases were registered, the mean age of the patients being 51.9 years. The most prevalent age group in males was 60-64 yrs (13.6%), while in females it was 50-54 yrs (12.8%). The commonest forms of cancer in males were bronchus and lung (17.6%) followed by stomach (7.3%), larynx (5.2%) and non Hodgkins lymphoma (4.5%). In females, cervix uteri (19.1%) and breast (16.3%), were the top ranking cancer sites followed by bronchus and lung (10.2%), ovary (6.1%) and stomach (3.8%). The present data provide an update of the cancer burden in Nepal and highlight the relatively young age of breast and cervical cancer patients.     

中国部分市县1998～2002年恶性肿瘤的发病与死亡

[目的]探讨中国人群肿瘤发病、死亡的流行特征.[方法]分析中国30个肿瘤登记处1998～2002年的肿瘤登记资料.[结果]全国30个肿瘤登记处覆盖人口37813997人,覆盖3.04%的全国人口.1998～2002年新病例386 910例,死亡病例266 033例.世界年龄结构调整恶性肿瘤发病率在78.4/10万～623.8/10万间;世界人口调整死亡率在78.9/10万～260.1/10万之间.[结论]中国最常见的恶性肿瘤,男性为肺癌、胃癌、肝癌和食管癌;女性为乳腺癌、食管癌、胃癌、肺癌、肝癌和子宫颈癌.     

Cancer prevalence in European registry areas.

BACKGROUND: Information on cancer prevalence is of major importance for health planning and resource allocation. However, systematic information on cancer prevalence is largely unavailable. MATERIALS AND METHODS: Thirty-eight population-based cancer registries from 17 European countries, participating in EUROPREVAL, provided data on almost 3 million cancer patients diagnosed from 1970 to 1992. Standardised data collection and validation procedures were used and the whole data set was analysed using proven methodology. The prevalence of stomach, colon, rectum, lung, breast, cervix uteri, corpus uteri and prostate cancer, as well as of melanoma of skin, Hodgkin's disease, leukaemia and all malignant neoplasms combined, were estimated for the end of 1992. RESULTS: There were large differences between countries in the prevalence of all cancers combined; estimates ranged from 1170 per 100000 in the Polish cancer registration areas to 3050 per 100000 in southern Sweden. For most cancers, the Swedish, Swiss, German and Italian areas had high prevalence, and the Polish, Estonian, Slovakian and Slovenian areas had low prevalence. Of the total prevalent cases, 61% were women and 57% were 65 years of age or older. Cases diagnosed within 2 years of the reference date formed 22% of all prevalent cases. Breast cancer accounted for 34% of all prevalent cancers in females and colorectal cancer for 15% in males. Prevalence tended to be high where cancer incidence was high, but the prevalence was highest in countries where survival was also high. Prevalence was low where general mortality was high (correlation between general mortality and the prevalence of all cancers = -0.64) and high where gross domestic product was high (correlation = +0.79). Thus, the richer areas of Europe had higher prevalence, suggesting that prevalence will increase with economic development. CONCLUSIONS: EUROPREVAL is the largest project on prevalence conducted to date. It has provided complete and accurate estimates of cancer prevalence in Europe, constituting essential information for cancer management. The expected increases in prevalence with economic development will require more resources; allocation to primary prevention should therefore be prioritised.     

Time Trend in Breast and Cervix Cancer of Women in India, (1990-2003)

The Indian Council of Medical Research (ICMR) started a National Cancer Registry Programme (NCRP)in the year 1982 with the main objective of generating reliable data on the magnitude and pattern of cancer inIndia. There are about 20 Population Based Cancer Registries (PBCR) which are currently functioning underthe network of NCRP. The present paper aims to provide the time trends in the incidence of breast and cervixcancer among females of India. The incidence data collected by Bangalore, Barshi, Bhopal, Chennai, Delhi andMumbai over the period 1990 to 2003 formed the sources of data. In the year 1990, cervix was the leading site ofcancer followed by breast cancer in the registries of Bangalore (23.0% vs. 15.9%), Bhopal (23.2% vs. 21.4%),Chennai (28.9% vs. 17.7%) and Delhi (21.6% vs. 20.3%), while in Mumbai breast was the leading site of cancer(24.1% vs. 16.0%). By the years 2000-3, the scenario had changed and breast had overtaken as the leading siteof cancer in all the registries except in Barshi (16.9% vs. 36.8%). The time trend analysis for these sites suggesteda significant decreasing trend in the case of cervix in Bangalore and Delhi registries, while the registries ofBhopal, Chennai and Mumbai did not show any significant changes. However, in the case of breast cancer, asignificant increasing trend was observed in Bhopal, Chennai and Delhi registries with Bangalore and Mumbairegistries demonstrating no such significant changes. Histopathologic confirmation for both malignancies wasfound to be more than 80% in these registries. It is concluded that in India the cervix cancer rates are decreasingwhile breast cancer is on the increase.     

Cancer survival in Incheon, Republic of Korea, 1997-2001

The Incheon cancer registry was established in 1997. Cancer is not a notifiable disease, hence registration of cases is done by active methods. The registry contributed survival data for 42 cancer sites or types registered during 1997-2001. The follow-up information has been obtained predominantly by passive methods, with median follow-up ranging between 1-44 months for various cancers. The proportion with histologically verified diagnosis for different cancers ranged between 16-100%; death certificates only (DCOs) comprised 0-51%; 49-100% of total registered cases were included for the survival analysis. The top-ranking cancers on 5-year age-standardized relative survival rates were testis (98%), thyroid (90%), ureter (87%), adrenal gland (86%), nonmelanoma skin (83%), corpus uteri (82%), Hodgkin lymphoma (81%), breast and cervix (74%). Five-year relative survival by age group showed a decreasing trend with increasing age groups for cancers of the stomach, small intestine, colon, gall bladder, larynx, lung, breast, cervix and ovary, and was fluctuating for other cancers.     

Cancer Prevalence in Aichi,Japan for 2012: Estimates Based on Incidence and Survival Data from Population-Based Cancer Registry

Background: Cancer is the leading cause of death among both men and women in Japan. Monitoring cancer prevalence is important because prevalence data play a critical role in the development and implementation of health policy. We estimated cancer prevalence in 2012 based on cancer incidence and 5-year survival rate in Aichi Prefecture using data from a population-based cancer registry, the Aichi Cancer Registry, which covers 7.4 million people. Methods: The annual number of incident cases between 2008 and 2012 was used. Survival data of patients diagnosed in 2006–2008 and followed up until the end of 2012 were selected for survival analysis. Cancer prevalence was estimated from incidence and year-specific survival probabilities. Cancer prevalence was stratified by sex, cancer site (25 major cancers), and age group at diagnosis. Results: The estimated prevalence for all cancers in 2012 was 68,013 cases among men, 52,490 cases among women, with 120,503 cases for both sexes. Colorectal cancer was the most incident cancer with 6,654 cases, accounting for 16.0% of overall incident cases, followed by stomach cancer with 5,749 cases (13.8%) and lung cancer with 5,593 cases (13.4%). Prostate cancer was the most prevalent among men, accounting for 21.5%, followed by colorectal and stomach cancers. Breast cancer was the most prevalent among women, accounting for 28.6%, followed by colorectal, stomach, and uterine cancers. Conclusion: This study provides cancer prevalence data that could serve as useful essential information for local governments in cancer management, to carry out more practical and reasonable countermeasures for cancer.     

Cancer prevalence in Central Europe: the EUROPREVAL Study.

BACKGROUND: Information on cancer prevalence is either absent or largely unavailable for central European countries. MATERIALS AND METHODS: Austria, Germany, The Netherlands, Poland, Slovakia, Slovenia and Switzerland cover a population of 13 million inhabitants. Cancer registries in these countries supplied incidence and survival data for 465 000 cases of cancer. The prevalence of stomach, colon, rectum, lung, breast, cervix uteri, corpus uteri and prostate cancer, as well as skin melanoma, Hodgkin's disease, leukaemia and all malignant neoplasms combined was estimated for the end of 1992. RESULTS: A large heterogeneity was observed within central European countries. For all cancers combined, estimates ranged from 730 per 100 000 in Poland (men) to 3350 per 100 000 in Germany (women). Overall cancer prevalence was the highest in Germany and Switzerland, and the lowest in Poland and Slovenia. In Slovakia, prevalence was higher than average for men and lower than average for women. This was observed for almost all ages. As shown by incidence data, breast cancer was the most frequent malignancy among women in all countries. Among men, prostate cancer was the leading malignancy in Germany, Austria and Switzerland, and lung cancer was the major cancer in Slovenia, Slovakia and Poland. The Netherlands had a high prevalence of both prostate and lung cancer. Time-related magnitude of prevalence within each country and the variability of such proportions across the countries has been estimated and cancer prevalence is given by time since diagnosis (1 year, 1-5 years, 5-10 years, >10 years) for each site. The weight of 1-year prevalence (248 per 100 000 among men and 253 per 100 000 among women) was <15% of total prevalence. Prevalent cases between 1 and 5 years since diagnosis represented between 22% and 34% of the total prevalence. Prevalent cases diagnosed from 5 to 10 years before (335 per 100 000 for men and 505 per 100 000 for women) represented between 17% and 23% of prevalent cancers. Finally, long-term cancer prevalence (diagnosed >10 years before), reflecting long-term survival, and number of people considered as cured from cancer were 490 per 100 000 for men and 1028 per 100 000 for women, with a range between 26% (The Netherlands, men) and 50% (Slovakia, women). CONCLUSION: It is clear from observing countries in Central Europe, that high cancer prevalence is associated with well-developed economies. This burden of cancer could be interpreted as a paradoxical effect of better treatments and thereby survival. It could also be taken as a sign for not being satisfied with the advances in treating patients diagnosed with cancer, and for supporting more primary prevention.     

Cancer survival in Kampala, Uganda, 1993-1997

The Kampala cancer registry was established in 1954 as a population-based cancer registry, and registration of cases is done by active methods. The registry contributed data on survival for 15 cancer sites or types registered in 1993-1997. For Kaposi sarcoma, only a random sample of the total incident cases was provided for survival study. Follow-up has been carried out predominantly by active methods, with median follow-up ranging from 4-26 months. The proportion with histologically verified diagnosis for various cancers ranged between 36-83%; death certificate only (DCO) cases were negligible; 58-92% of total registered cases were included for survival analysis. Complete follow-up at five years ranged between 47-87% for different cancers. Five-year age-standardized relative survival rates for selected cancers were Kaposi sarcoma (22%), cervix (19%), oesophagus (5%), non-Hodgkin lymphoma (26%), breast (36%) and prostate (46%). None survived beyond 5 years for cancers of the stomach and lung. Five-year relative survival by age group was fluctuating with no definite pattern or trend emerging and no survivors in many age intervals.     

Cancer Occurrence in Iran in 2002, an International Perspective

For almost 30 years no population-based cancer statistics have been available with which to estimate the cancer ‍burden in Iran. In 2002 and 2003 two separate reports of population based cancer registries were published from ‍Iran and the cancer incidence rates from these sources have permitted informed estimates of cancer incidence and ‍mortality to be prepared. They suggest that more than 51,000 cases of cancer are diagnosed and 35,000 deaths due to ‍cancer occur each year. The 5 most common cancers in males (by ASR) are stomach (26.1 per 105), esophagus (17.6 ‍), colon-rectum (8.3), bladder (8.0) and leukemia (4.8), and in females are breast (17.1), esophagus (14.4), stomach ‍(11.1), colon-rectum (6.5) and cervix uteri (4.5). The incidence rates of esophageal and stomach cancer in Iran are ‍high, well above the world average, while the incidence of lung cancer is very low. Breast cancer, although the most ‍common cancer of females in Iran, has rates that are low by world standards, especially those observed in Europe ‍and USA. Similarly, the incidence of cervix cancer in Iran is very low, even lower than such low risk countries as ‍China, Kuwait and Spain. Comparing these rates with the data of 30 years ago, the incidence of esophageal cancer ‍has decreased dramatically, but gastric cancer has increased about two fold.     

中国肿瘤登记地区2008年恶性肿瘤发病和死亡分析

[目的]利用全国肿瘤登记中心2011年收集的各登记处肿瘤登记资料,分析2008年全国肿瘤登记覆盖地区癌症的发病与死亡水平。[方法]通过对全国56个登记处上报的2008年肿瘤登记数据进行全面审核与评价,选取其中41个登记处的数据进行合并,按地级以上城市和县(县级市)划分城市和农村,分别计算发病(死亡)率、年龄别发病(死亡)率、标化发病(死亡)率、构成比、累积发病(死亡)率。[结果]2008年中国肿瘤登记地区的41个登记处合计覆盖登记人口66 138 784人(城市52 158 495人,农村13 980 289人),共报告新发病例197 833例,死亡病例122 136例,病理诊断比例为69.33%,只有死亡证明书比例为2.23%,死亡/发病比为0.62。中国肿瘤登记地区恶性肿瘤发病率为299.12/10万(男性330.16/10万,女性267.56/10万),中标发病率148.75/10万,世标发病率194.99/10万,累积发病率(0~74岁)为22.27%。城市地区发病率为307.04/10万,中标发病率148.64/10万,农村地区发病率为269.57/10万,中标发病率151.02/10万。恶性肿瘤死亡率为184.67/10万(男性228.14/10万,女性140.48/10万),中标死亡率84.36/10万,世标死亡率114.32/10万,累积死亡率(0~74岁)为12.89%。城市地区恶性肿瘤死亡率为181.54/10万,中标死亡率79.21/10万。农村地区恶性肿瘤死亡率为196.34/10万,中标死亡率106.05/10万。中国肿瘤登记地区无论城市还是农村,恶性肿瘤发病占前几位的主要是肺癌、胃癌、结直肠癌、肝癌、食管癌、胰腺癌、脑瘤、淋巴瘤、女性乳腺癌和宫颈癌等,占全部恶性肿瘤发病的75%左右。恶性肿瘤死亡前几位的主要是肺癌、胃癌、肝癌、食管癌、结直肠癌、胰腺癌、乳腺癌、脑瘤、白血病和淋巴瘤,约占全部恶性肿瘤死亡的80%左右。农村地区发病、死亡是以食管癌、胃癌为主的消化系统恶性肿瘤较高,其次为肺癌、肝癌、结直肠癌,而城市地区发病、死亡以肺癌位居第一位,女性以乳腺癌位居女性发病第一位,其次是肝癌、胃癌、结直肠癌较高。[结论]肺癌、胃癌、结直肠癌、肝癌、食管癌、女性乳腺癌为威胁我国居民健康的主要恶性肿瘤,为我国今后恶性肿瘤的防控重点,同时,肿瘤的防控工作还应考虑癌谱在地区和性别上的差异。     

The epidemiology of cancer in Chile

Despite the fact that cancer is underreported in most of Latin America, available data suggest that it is a major cause of death throughout the area. The most frequent sites among males are the stomach, lung, and prostate; among females, the cervix, stomach, and breast are affected most often. Only Cuba has a nationwide registry; Brazil, Colombia, and Peru have registries limited to areas. Within this context, Chile ranks second in the world in age-adjusted mortality rates from stomach cancer. Other leading sites are the lung, cervix, and breast. Stomach cancer exhibits high- and low-risk areas in Chile, with distinct epidemiologic characteristics. A case-control and nitrate ecology study funded by the United States National Cancer Institute is underway, and the Japanese International Cooperation Agency is launching a 3-year mass screening program.     

Cancer survival in the Gambia, 1993-1997

The national cancer registry of the Gambia was established in 1986 as part of the Gambia Hepatitis Intervention Study in collaboration with IARC, France; Medical Research Council (MRC) Laboratories of the UK; and the Government of the Gambia at MRC, Banjul. Registration of incident cancer cases is done by active and passive methods. For this study, the registry contributed data on survival for six cancer sites or types registered during 1993-1997. Follow-up has been carried out predominantly by active methods with median follow-up ranging between 1-6 months. The proportion of histologically verified diagnosis for various cancers ranged between 1-45%, and 54-82% of total registered cases were included for survival analysis. Complete follow-up at five years from the incidence date ranged between 81-98% for different cancers. The 5-year age-standardized relative survival for selected cancers were cervix (23%), non-Hodgkin lymphoma (22%), breast (10%), stomach (4%) and liver (3%). The 5-year relative survival by age group showed fluctuations with no definite pattern or trend emerging, and with no survivors in many age intervals.