Trends in survival rates of cancer in Cuba

Reports of population-based survival rates of cancer from developing countries are infrequent. In Latin America, only the Cancer Registry of Puerto Rico has published population-based survival data. The National Cancer Registry of Cuba has achieved three survival studies with cases incident in 1976, 1982 and 1988–1989. This article deals with the global observed and relative survival rates estimated in the latter study. Survival time trends are analysed. In the period 1988–1989, 12,985 primary cancer cases were included from the most common cancer sites, with the exclusion of cancer in situ cases and 8900 cases reported by death certificate only (DCO) (35.8%). The vital status of cases was checked up to 31 December 1994 using a mixed follow-up system with the exclusion of 2900 cases lost to follow-up (11.2%). DCO proportions are shown for the major sites and compared to those of 1982. Observed survival rates were estimated by Kaplan–Meier method using the SPSS Statistical Software. The relative rates were estimated by the Hakulinen's Computer Program Package for Cancer Survival Studies (1988) using life tables from Cuban population. Statistical comparisons of survival curves by year of diagnosis were achieved by using the Log–Rank and Pearson statistic tests. Global results are shown by year of follow-up and a comparative analysis is done in time and with internationals values. Survival rates decreased in the period 1982/1988–1989 for colon, prostate and lung cancer. Prostate cancer shows a low five years relative survival rate when compared with the USA, but its observed rate is comparable with Puerto Rico's. Figures for mouth and lung cancer were comparable with the corresponding figures of the USA and Europe. Breast and cervix cancers rates are comparable with the European mean and the blacks in USA.     

The Cuban National Cancer Registry: 1986–1990

In Cuba, the illness that produces most deaths among 1–64–year-olds is cancer. Over 65, it is the second cause of death after heart diseases. A National Cancer Registry was created 1964. Its main goals are to register all malignant neoplasms diagnosed in the country, to study this disease from the statistical and epidemiological point of view and to aid in the health control and planning of cancer fighting resources. This paper presents the results based on cases registered from 1986 to 1990. More than 50% of incidence and mortality caused by cancer is confined to the five major primary sites: lung, prostate, colon, breast and cervix. World population standardised rates by 100,000 inhabitants for the period 1986–1990 were 218.2 in males and 183.7 in females for incidence and 138.4 in males and 95.1 in females for mortality. Cancer incidence distribution by provinces shows two major regions: western-central, where higher risks of lung, breast, prostate and colon cancers are found, and eastern where very high risk of cervix cancer is observed. Although an improvement of the information quality indexes has been reported by the National Cancer registry in the studied period of time, quality of the data remained very poor according to the international standards. However, the results obtained by the National Cancer Registry seem to be a valuable tool to evaluate the cancer burden and, in particular, to control and eventually modify the tasks of the National Cancer Control Program in Cuba.     

Changes of the incidence and survival in pediatric malignant tumors between 1988-1997, according to the data of the Hungarian Pediatric Cancer Registry]

This paper reports the results of the epidemiological surveillance of childhood malignancies in Hungary from 1988 through 1997, according to the database of the Hungarian Paediatric Cancer Registry. The number of analysed cases was 2146. The crude incidence of all childhood malignancies was 132 per one million person-years. The number of new cases diagnosed in Hungary varied between 240 to 280 per year. This number did not change significantly over the observed period in spite of the decreasing number of children in Hungary, therefore, the incidence showed a significant increase of 3.3% per year. The authors also present data about the geographical distribution of childhood cancer in Hungary and survival rates for different tumour types. The 10-year overall survival rate of all malignant diseases diagnosed in Hungary during the analysed ten-year period was 62.6%.     

Trends in incidence of and mortality from invasive cancer of the uterine cervix in Scotland (1975–1994)

Objective: I. To identify major trends in the incidence of and mortality from invasive cancer of the cervix uteri in Scotland during the twenty year period 1975–1994; II. to consider the extent to which these trends may have been shaped by the introduction of systematic cervical screening.Design: Analysis of annual age standardised and age specific rates for incidence and mortality, based on data collected by the Scottish Cancer Registry and the General Register Office for Scotland.Setting: Scotland.Subjects: Women registered with the Scottish Cancer Registry as having developed invasive cancer of the cervix during the period of interest.Results: Annual all ages incidence rates of invasive cervical cancer show little overall change over the period 1975–1989, but exhibit a pronounced decline from 1990 onwards. All-ages mortality rates show clear evidence of decline during the period 1975–1994, the rate for 1994 being some 30% lower than that for 1975. Annual age-specific incidence rates show different patterns by age group, with clear evidence of decreasing trends in the age range 50–64 years but different patterns in younger and older age groups. Most age groups show steep declines in incidence from 1990 onwards. Age specific mortality rates for 1975–1994 exhibit the most pronounced decreasing trends in the age range 50–64 years. The trends identified are broadly similar to those experienced in England and Wales over an approximately comparable period.Conclusions: The overall (all ages) incidence of invasive cervical cancer in Scotland changed little during the period 1975–1989, but declined sharply from 1990 onwards. The most pronounced decline in incidence across the period 1975–1994 appears to have taken place in the age range 50–64 years. This decline has been accompanied by a commensurate fall in mortality in the same age range. These reductions in incidence and mortality may be attributable in part to increased coverage of cervical screening programmes during the period of interest. Evidence from other studies suggest that, without the increased coverage of cervical screening achieved during this period incidence rates in Scotland might have been seen to increase.     

Long term survival of upper aerodigestive tract cancer in male patients in the Umbria region (Italy)

The aim of this work was to make a study of the whole population of a central Italian region, the Umbria region – cancer survival rates for the upper aerodigestive tract, which includes cancers of the head and neck (tongue, oral cavity, pharynx), oesophagus and larynx. In Italy cancer survival rates do not cover entire regions but single municipalities or provinces. Cases of incidence were derived from an ad hoc survey carried out during the period 1978–1982. Starting from the nominative data, we studied up to 15 years 245 head and neck, 87 oesophagus and 321 larynx cases of cancer in males. Data for female cases were not considered because of the small number. Cancer cases were followed up mainly by verification at the Registry Office of several municipalities, the Regional Death Registry and the list of persons under the Regional Health Service. Observed survival rates for head and neck cancer were 0.63, 0.29, 0.17 and 0.12 at 1, 5, 10 and 15 years of follow-up respectively; rates for cancers of the oesophagus and larynx were 0.30, 0.08, 0.06, 0.03 and 0.79, 0.54, 0.41, 0.30 respectively. Relative survival rates were 0.65, 0.34, 0.24, 0.23 for cancer of the head and neck, 0.31, 0.10, 0.09, 0.08 for cancer of the oesophagus, and 0.81, 0.63, 0.59, 0.56 for cancer of the larynx, at 1, 5, 10 and 15 years of follow-up. The worst survival rates were observed for oesophagus and hypopharynx. Overall survival values for Umbrian patients were relatively good, being higher than survival data reported for a similar period by Italian Cancer Registries. They were also strikingly similar to survival rates for England and Scotland.     

Epidemiological characteristics of gastric cancer in Vojvodina

Epidemiological characteristics of gastric cancer in the province of Vojvodina were analyzed on the basis of official data of the Cancer Registry of Vojvodina and the records of the Bureau of Census of Vojvodina for the years 1982–1991. In the year 1991, the cases of gastric cancer accounted for 7.8% of all malignant neoplasms in males, ranking thus third, whereas in females, with 5%, it was in seventh place. At the same time, in the structure of deaths from malignant neoplasms, gastric cancer was on the second place both in males (9.1%) and females (7.8%). The male/female gastric cancer mortality ratio was 1.7:1. Incidence and mortality rates showed the tendency of a slow but steady decrease in both sexes during the observation period. The age-standardized incidence rate (world population) was 25.9 per 100,000 for men and 9.4 for women in average. In comparison with the corresponding data of the registries of Europe and of the world, Vojvodina falls in the range of moderately high rates. The age-specific incidence and mortality rates show a strong increase after the age of 55, reaching the highest values in the ages 75– 79. Thus it can be said that gastric cancer is a disease of the elderly. Total five-year survival is low, which is a common observation for this kind of neoplasm.     

Declines in lung cancer rates--California, 1988-1997

Cigarette smoking is the leading cause of lung and bronchus cancer (1). During 1988-1997, per capita cigarette smoking in California declined more than twice as rapidly compared with the rest of the country (2). To characterize lung cancer incidence in California, data from the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) program were compared with data from the population-based California Cancer Registry (CCR). This report summarizes the results of that analysis, which indicated that during 1988-1997, age-adjusted lung cancer incidence rates in California declined significantly compared with stable incidence rates for the combined SEER area of five states and three metropolitan areas.     

Increasing risk of asthma without other atopic diseases in school children: A repeated cross-sectional study after 13 years

Some children develop asthma and other atopic diseases, others asthma without atopic diseases. To better understand secular trends, we estimated the relative increase in asthma in children with (atopy related asthma) and without (non-atopy related asthma) other atopic diseases (eczema or hay fever) in two samples of school children born, 1965–1975 (n = 1674) and 1978–1988 (n = 2188). By analysing the samples as historical cohorts, age-specific prevalence rates were estimated and incidence rates were calculated (number of new cases by 1000 personyears under risk). Cox regression was used to estimate the relative risk (RR) of asthma by year of birth. The point prevalence of asthma was 1.9% (95% CI: 1.4–2.4) in the 1965–1975 cohort and 4.6% (95% CI: 3.8–5.4) in the 1978–1988 cohort for three-year old children, and remained fairly constant throughout childhood. The age-specific prevalence of non-atopy related asthma increased relatively more from 1965–1975 to 1978–1988 compared to atopy related asthma. The age-specific incidence rates of asthma showed that the RRs comparing the two cohorts tended at all ages to be highest for non-atopy related asthma. The relative risks of non-atopy related asthma by gender and birth cohort, showed that the effect of cohort was higher for non-atopy related asthma, aRR: 4.0 (95% CI: 2.5–6.5), than for atopy-related asthma aRR: 2.0 (95% CI: 1.3–3.2). Children without other atopic diseases have a higher relative risk of being diagnosed with asthma than children with other atopic diseases across all ages comparing two samples of school children born 1965–1975 and 1978–1988.     

Cancer incidence among finnish rubber workers

Summary A follow-up study was carried out among workers in the processing and tire and tube fabrication departments of a Finnish rubber plant. A total of 1,331 workers were followed up for cancer through the files of the Finnish Cancer Registry from 1953 to 1976 (11,709 person years). The expected number of cancer cases was calculated on the basis of the age and sex-specific incidence rates for the urban population of the surrounding province. Twenty-one cancer cases were found against 18.9 expected (RR 1.1, 95% confidence interval 0.7–1.7). The risk of cancer of the digestive organs, respiratory organs, and urinary bladder was higher than expected, and the risk increased with the length of the follow-up time. However, the differences were not statistically significant.     

Population-based study of cutaneous malignant melanoma in the Granada province (Spain), 1985-1992

Cutaneous melanoma has received substantial attention during the last years because of the increase in its incidence which has been registered in many countries. This paper aims at describing the incidence and characteristics of all new cutaneous malignant melanoma cases during 1985–1992 reported to the Granada Cancer Registry (Spain) in the context of Mediterranean populations. A population-based study with 247 cutaneous melanoma cases was carried out. The variables used were: sex, age, anatomic site, hystological type, level of invasion and tumour thickness. The Age-Standardised incidence Rate per World population (ASRW) was 2.9 for males and 3.7 for females in the whole period. An increasing incidence trend for both males and females was found. The ASRW in 1985–1987, 1988–1990 and 1991–1992 was respectively 2.2, 2.9 and 3.2 for males and 3, 3.4, 4.7 for females. The most frequent location was trunk for males (36%) and lower extremities for females (44%). The most frequent hystological type for both males and females was superficial spreading melanoma. Seventy-six percent of males and 60% of females were diagnosed Clark's level III or over. Average tumour thickness was 3.3 mm for males and 2.4 mm for females. The results of this study can be a guidance for the setting up of health policies which would contribute to the prevention of the disease and to an improvement in care. Because of the increase in incidence rates and the high percentage of cases which were diagnosed at advanced stages, it is advised that prevention campaigns are addressed to the Granada population.     

Trends in cancer mortality of the digestive tract in Belgrade,Yugoslavia, 1975–1989

During the period of 1975–1989, in the Belgrade population increasing mortality trends were established for colon and rectal cancer, cancer of the pancreas and gallbladder and bile ducts cancer, for both sexes, and for esophageal cancer in males. Stomach and liver cancer mortality decreased in females. In males, stomach cancer mortality after a prolonged steady decrease suddenly rose in the years 1988 and 1989. Mortality rates series for esophageal cancer in females and for liver cancer in males did not fit any usual trend function.     

Lung cancer in the Netherlands in the period 1989-1997: the epidemic is not over yet

OBJECTIVE: To describe and interpret changes in incidence, mortality and survival of lung cancer in the Netherlands in the period 1989-1997. DESIGN: Secondary data analysis. METHODS: Data on the incidence of lung cancer were collected from the Dutch Cancer Registration (1989-1997), on mortality from Statistics Netherlands (CBS; 1989-1994), on the incidence of lung cancer in other European countries from EUROCIM (1990-1994), on survival of Dutch lung cancer patients from the Comprehensive Cancer Centre Amsterdam (1988-1997) and the Comprehensive Cancer Centre South (1988-1992) and on survival of other European lung cancer patients from EUROCARE (1985-1989). Incidence rates were calculated per 100,000 person years and standardized by age according to the European population structure. Survival was calculated as the ratio of observed survival among the lung cancer patients and the expected survival of the general population. RESULTS: The incidence of lung cancer among men decreased from 109 to 93, whereas that among women increased from 18 to 23. The incidence of lung cancer among Dutch men was high in comparison to other European countries, whereas that among women was average. The trends in lung cancer incidence were probably related to the trends in past smoking behaviour. Mortality decreased among men from 106 to 91 and increased among women from 15 to 20. Survival was better for younger patients, a localised tumour, and better for squamous cell carcinoma or adenocarcinoma than for large-cell undifferentiated or small-cell carcinoma. The relative 5-year survival was 12%, the relative 1-year survival 39%; these were good in comparison with other European countries. CONCLUSION: The incidence and mortality of lung cancer among Dutch men decreased, but still in 1997 almost 20 men in the Netherlands died each day of lung cancer. Among women the end of the increase is not in sight and in 1997 over 5 women died each day of lung cancer.     

Evaluation of service screening for breast cancer by clinical breast examination using regional cancer registry data

MATERIALS: (1) Screening test: The study utilized data from a regional cancer-screening center from April 1, 1997, to December 31, 1998. A total of 51,700 women underwent screening at this center during this period. All incident cases of breast cancer in these women were derived from the files of the Yamagata Prefectural Cancer registry and sensitivity, specificity and positive predictive value were then estimated. False negative cases were defined as occurring in women who tested negative but were registered as having breast cancer in the cancer registry within 12 months after screening. (2) Effectiveness of screening: The target population comprised female cases with breast cancer registered in the Yamagata Prefectural Cancer Registry from January 1, 1989 to December 31, 1998. During this period, a total of 2,746 cases were registered. Survival probabilities for breast cancer cases were estimated according to method of detection using Kaplan-Meier method. Overall survival probability of the screen-detected group was compared with the not screen-detected group using the log-rank test. Point estimates of 5- and 9-year survival rates between groups were compared using z statistics. RESULTS: (1) Screening detected 27 breast cancer cases, while 31 false negative cases were identified. Sensitivity, specificity and positive predictive value were 46.6% (95% confidence interval (95% CI), 33.3-60.1%), 97.3% (95% CI, 97.2-97.5%) and 1.9% (95% CI, 1.3-2.8%), respectively. (2) Overall survival rate for the screen-detected group was significantly higher than that for the not screen-detected group (P<0.001), with 11.6% (95% CI, 8.0-15.2%) and 13.1% (95% CI: 5.3-20.8%) differences in 5-year and 9-year survival probabilities, respectively. CONCLUSION: Cancer screening by clinical breast examination in Yamagata has improved survival from breast cancer for females. However, the screening sensitivity is insufficient for effective mass screening purposes.     

Was Breast Conserving Surgery Underutilized for Early Stage Breast Cancer? Instrumental Variables Evidence for Stage II Patients from Iowa

Objective. To estimate the average survival effects of breast conserving surgery plus irradiation relative to mastectomy for marginal stage II breast cancer patients in Iowa from 1989–1994.
Data Sources/Data Setting. Secondary linked Iowa SEER Cancer Registry—Iowa Hospital Association discharge abstract data for women in Iowa with stage II breast cancer from 1989–1994.
Study Design. Observational instrumental variables (IV) analysis.
Data Collection/Extraction Methods. Women with stage II breast cancer from the Iowa SEER Cancer Registry 1989–1994 who received all of their inpatient care in Iowa were linked with their respective hospital discharge abstracts.
Principal Findings. Breast conserving surgery plus irradiation decreased survival relative to mastectomy for marginal stage II breast cancer patients in Iowa during the early 1990s. In this study marginal patients were those whose surgery choices were affected by differences in area treatment rates and access to radiation facilities.
Conclusions. If marginal patients are representative of patients whose treatment choices would be affected by changes in treatment rates, an increase in the breast conserving surgery plus irradiation rate for stage II early stage breast cancer patients would have decreased survival in Iowa during the early 1990s. Further research with newer data and broader samples is needed to make more current and specific assessments.     

Cervical cancer rates by population size of towns: Implications for cancer control programs

Incidence rates and standardized incidence ratios (SIRs) for invasive and in situ cervical cancers diagnosed in 1982–87 were analyzed according to total population size of 148 towns, using data from the population-based Connecticut Tumor Registry. Previous studies have not considered socioeconomic or sociodemographic variables in analyzing cervical cancer rates in urban-rural or population density groups. In multiple regression analyses, increases in SIRs for invasive and in situ cancers from medium-sized to large towns were explained by differences in poverty prevalence or other sociodemographic variables. Nevertheless, cancer screening programs (aimed at preventing invasive cancer through early detection) could be targeted to some extent on the basis of town size category, because larger towns include large numbers of poorer and minority women with higher rates of invasive cervical cancer. SIRs for in situ cancer were significantly elevated in the largest towns (100,000+ total population), and primary prevention programs could target these larger towns with a higher prevalence of poverty.Anthony P. Polednak is Senior Research Scientist; Dwight T. Janerich is Professor; both in the Department of Epidemiology and Public Health, Yale School of Medicine, New Haven, CT 06510.John T. Flannery is Director, Connecticut Tumor Registry, Connecticut Department of Health Services, 150 Washington Street, Hartford, CT 06106This work was supported in part by a grant from the National Cancer Institute (CA-42101), as part of the Cancer Prevention Research Unit at the Yale School of Medicine.     

Breast and cervical cancer survival: making sense of ‘league tables’

During 1998, the Department of Health proposed to use survival rates of cervical and breast cancer in the 1989/90 incidence cohort as indicators of care. Valid interpretation was of concern within Trent and the Trent Cancer Registry responded by performing additional analyses. Trent Cancer Registry registrations for 1989/90 were re-analysed and the stability of districts' ranks for that cohort was investigated using random simulation techniques. Stability of ranks across more recent cohorts was investigated and attempts made to use all available information.The Department of Health's analyses were confirmed by our re-analysis of the 1989/90 cohort: Rotherham residents appeared to have the "worst" survival for cervical cancer, and Sheffield residents for breast cancer, although not statistically significantly so. Random simulations indicated that ranks based on a single cohort are not stable: for example Sheffield (ranked tenth for 1-y breast cancer survival) was ranked third or better in 6% of randomisations. Ranks were also unstable across cohorts: for example Rotherham 1-y cervical cancer survival was ranked tenth for 1989/90, fifth for 1991/92 and tenth for 1993/94. Analysis of 3-y running averages provided better information than the league table approach. Most districts improved over time, to different degrees, and similar sized gaps remained between the "best" and the "worst" districts. This analysis illustrates the need to be circumspect when interpreting "league tables" based on a single year or cohort analysis. League tables are based on ranks: clearly a large difference in rank may reflect only trivial (ie medically unimportant) differences in actual outcome. Lack of a statistically significant difference in survival between two districts does not mean their survival is equivalent. Even for a common cancer, like breast cancer, rankings were unstable from cohort to cohort. At the Registry we propose to perform these trend analyses routinely in future, adjusting, when possible, for the effects of deprivation and stage at diagnosis.