Clinically applicable bulk isolation of blood CD34+ cells for autografting in children

The quality of population-based cancer registries has been measured by the indices of the proportion of total incident cases (DCO%) registered by death certificate only (DCO), and the ratio of incidence to mortality (I/D ratio). Recently it has been recommended that DCO% should be used as an index for the reliability of diagnosing cancers and that the proportion of cases first notified via death certificate (DCN, DCN%) be used as an index for the completeness of registration. Parkin introduced a method to estimate the registration rate, the estimated proportion of the "true incidence" that are registered in population-based registries. We recommend a modified method for estimating the registration rate for cancer registries where DCN% is relatively high, as it is in Japan, as Parkin's method may overestimate the registration rate. The method is as follows: the registration rate = (1-DCN% x 1/D ratio)/(1-DCN%). The registration rates at the Osaka Cancer Registry between 1966 and 1992 were estimated using our method. During this period, the yearly registration rate was 74.6-78.4% for males and 69.1-73.3% for females. When the cancer cases were looked at according to site, the yearly registration rate was 74.2-81.6% for stomach cancer, 81.2-89.3% for lung cancer, and 71.3-76.9% for uterine cancer. These results show that the registration rate is high for cancers that have an unfavorable prognosis and low for cancers that have a favorable prognosis. We recommend that all cancer registries in Japan calculate the completeness of registration by utilizing DCN defined as the sum of DCO plus cases not reported as cancer but with supportive clinical information of such obtained through survey of the registry for DCN.     

Cancer incidence in The Netherlands in 1989 and 1990: first results of the nationwide Netherlands cancer registry. Coordinating Committee for Regional Cancer Registries

The first results are presented of the newly established Netherlands Cancer Registry, which covers the whole Dutch population (approximately 15 million people). The registry receives data on incident cancer cases from nine autonomous regional cancer registries. Notification occurs primarily through the national registry of all pathology and haematology departments, with additional reporting by medical records' departments of all hospitals. Data on cancer patients are abstracted directly from the medical records by trained registration clerks. In the years 1989-1990, the most common cancer sites among males were cancers of the lung, prostate and colon. For females, breast cancer ranked first, followed by cancer of the colon and lung. A comparison with age-adjusted (world standard population) incidence rates reported by other western cancer registries showed a relatively high incidence of lung cancer among males (72.9 per 100,000) and breast cancer among females (76.2 per 100,000). Through its near completeness and the high quality of the registered data, the Netherlands Cancer Registry offers excellent opportunities for epidemiological and clinical research.     

Surgical procedures associated with risk of ovarian cancer

BACKGROUND: This historical cohort study was conducted to examine the relationship between gynaecological surgery and ovarian cancer risk. METHODS: Women were included if they had had tubal ligation, hysterectomy, or unilateral ovariectomy in Ontario between March 1979 and April 1993. The cohort was linked to the Ontario Cancer Registry and the Ontario mortality file. Person-years in the cohort were accumulated until death, the removal of both ovaries, a diagnosis of ovarian cancer, or the end of the study period 31 December 1993. Observed cancers were compared to expected based on Ontario age- and calendar period-specific incidence rates. RESULTS: For tubal ligation and hysterectomy, fewer ovarian cancers were observed than were expected by age, calendar year of procedure, and length of follow-up; the observed/expected ratios were generally statistically significant. In contrast, no protective effect was evident for unilateral ovariectomy; in fact statistically significant excess cancers were seen in early follow-up periods. Observed/expected ratios were nearly identical and somewhat protective for the two strata defined by whether or not the ovaries were visualized. Disruption of the ovarian pathway conferred a protective effect, while no disruption significantly increased risk. CONCLUSIONS: The data do not support screening bias although short-term follow-up data indicate the possibility of detection bias. The long-term follow-up data, as well as the data on pathway disruption, are consistent with the hypothesis that the surgical procedures themselves may produce a protective effect against ovarian cancer, through alteration of the hormonal environment and/or by physical destruction of a carcinogen's route to the ovary.     

Cancer incidence and mortality in France in 1975-95

The aims of the European Network of Cancer Registries (ENCR) are to improve the quality, comparability and availability of cancer registry data in Europe. This paper on cancer incidence and mortality in France presents the most recent available data, with short-term projections to 1995, and a commentary based, where possible, on epidemiological research carried out in France. Cancer incidence in men in France increased throughout the study period 1975 to 1995, from 92,000 new cases in 1975 to about 135,000 in 1995. This increase was partly due to the ageing of the French population, but incidence rates have also increased, particularly from 1975 to 1985. The trend appears to be levelling off in the 1990s, with an incidence rate in 1995 of about 482 per 100,000 (this and subsequent rates quoted are standardized to the European Standard Population). Among women, the all-cancer incidence rates also increased during the 1970s and 1980s. Although the rate of increase was less pronounced than in men, the trend is continuing in the 1990s. The estimated age standardized rate in 1995 was 309 per 100,000, representing 104,000 new cases. The main components of these changes in the last decade were, for men, increases in large bowel and prostate cancer, which have been partly compensated for by decreases in oral cavity, larynx and stomach cancer. For women the trend was dominated by the continuing increase in breast cancer with increases also in large bowel and lung cancers. Of the numerically important cancers in women, only stomach cancer has shown a clear decline. The situation in 1995 was that breast cancer remained the predominant cancer affecting women in France, accounting for almost one third of all new cases of cancer diagnosed and one fifth of cancer deaths. The next most frequent cancers in women were those of the large bowel. Regrettably, incidence rates of both breast and bowel cancer are increasing in women. For men in France the most frequent cancers in 1995 were those of the prostate, large bowel and lung, all of which increased in incidence since 1975. Although it is estimated that there will be more newly diagnosed cases of prostate cancer than lung cancer in 1995, the latter will cause many more deaths, particularly of young men.     

Prostate cancer in Denmark: a 50-year population-based study

OBJECTIVES: To review the trends in prostate cancer (PC) incidence and mortality rates in Denmark during a 50-year period. METHODS: A population-based register study was performed of all new cases of PC recorded in the Danish Cancer Registry from 1943 to 1992. RESULTS: The age-standardized incidence rate for PC increased from 11.5/100,000 in 1943 to 1947 to 30.9/100,000 in 1988 to 1992. Age-specific incidence rates increased in all age groups over 50 years of age. Mortality rates increased from 13.5/100,000 in 1953 to 1957 to 17.8/100,000 in 1988 to 1992. No major changes in the distribution of age, stage at the time of diagnosis, or in diagnostic procedures were found, indicating that the observed change in incidence rates was not caused by attempted early detection or changes in diagnostic strategy. CONCLUSIONS: Our data suggest that the increased PC incidence observed during the period of cancer registration in Denmark represents a true increase in the number of patients with clinical PC.     

Cancer patterns in three African populations compared with the United States black population

Cancer incidence rates and patterns in three African populations in the Gambia, Mali and South Africa, have been compared with corresponding data on the Black population in Connecticut, USA. In the African populations, total rates for cancer are much lower than that of US Blacks, even allowing for under-reporting. Chief cancers are those of the oesophagus, liver and cervix. In Mali, stomach cancer is very common. As to trends, among South African Blacks, a population in transition, rates are rising, albeit slowly, of cancers of prosperity--prostate, lung, breast and colon-rectum. Salient questions are: can the number of cancers of underprivilege be lessened, and can cancers linked with rising socioeconomic states be restrained? Discussions of common risk factors, including diet, reproduction, smoking and drinking practices, indicate that for Africans as a whole, continuing poverty will prevent major changes in cancer pattern and rises in occurrence of the disease. However, should prosperity increase for Africans in big cities, rates are ultimately likely to attain those prevailing in the US Black population. Significant avoiding action seems almost impossible.     

Accuracy and completeness of the registration of childhood leukaemia in The Netherlands, 1989-1992

In the Netherlands, childhood leukaemia is recorded by the Dutch Childhood Leukaemia Study Group (DCLSG, set up in 1972) and by nine regional cancer registries which together form the Netherlands Cancer Registry (NCR, set up in 1989). The data files from the incidence years 1989-1992 of the two registries were linked in order to evaluate accuracy and completeness and to calculate and equalise the incidence rates for childhood leukaemia in The Netherlands. Unlinked records or records with disagreements (birth date, sex, type of leukaemia and incidence date) were checked by the DCLSG and by the regional cancer registries. The DCLSG recorded 431 cases of childhood leukaemia, while the NCR recorded 434 cases. After record linkage and review of the cases, it was concluded the 445 records should have been recorded as childhood leukaemia. The NCR had recorded 425 of the 445 correct cases (95.5%), but had missed 20 cases (4.5%). The DCLSG had recorded 431 of the 445 correct cases (96.9%) and had missed 14 cases (3.1%). In addition, the NCR had recorded 9 cases incorrectly as childhood leukaemia. Part of the disagreement was caused by differences in coding rules (definition of non-Hodgkin's lymphoma (NHL) and the myelodysplastic syndrome versus leukaemia). It could be concluded that the quality and completeness of the two registries was very high. Regular comparison of the recorded data will help to reveal the inherently problematic disagreement between definitions and coding.     

The National Cancer Data Base report on completeness of American Joint Committee on Cancer staging in United States cancer facilities. The American College of Surgeons Commission on Cancer and the American Cancer Society

BACKGROUND: American Joint Committee on Cancer (AJCC) staging is increasingly accepted as a prognostic standard for cancer management. The Commission on Cancer requires approved cancer programs to use AJCC staging for all cancers. Previous studies document increasing use of AJCC staging by hospitals with cancer programs. This review examines programmatic and clinical factors affecting AJCC staging completeness. METHODS: The data are registry records submitted to the National Cancer Data Base (NCDB) for cases diagnosed during 1993 or, for comparison, 1988. RESULTS: The mean facility staging rate was 87% in 1993, up from 65% in 1988. Approximately 64% of facilities staged greater than 90% of their stageable cases; 3% staged less than 5%. Even facilities with "complete" staging implementation were unable to stage substantial portions of some sites. Accessibility of tumor and overall prognosis affected the choice between pathologic and clinical staging. Staging completeness and the mix of pathologic and clinical staging also differed by state of the reporting facility. CONCLUSIONS: AJCC staging use is high among common tumors for which treatment is dependent upon stage of disease. However, if accurate staging is not expected to affect the treatment or outcome of the case or the overall outcome is poor, staging is less frequently recorded.     

Treatment of aggression and irritability after head injury

Epidemiological characteristics of colorectal cancer may differ by particular anatomical subsite, suggesting that the subsite-specific colorectal cancers may represent different disease entities. This study explored the time trends over a 23-year period in colorectal cancer incidence at various subsites by sex and age group. Data on the incidence of colorectal cancer were obtained from a population-based cancer registry in Shanghai, People's Republic of China. Between 1972 and 1994, 30,693 patients with colorectal cancer were registered at the Shanghai Cancer Registry. The overall age-adjusted colorectal cancer incidence rates increased > 50%, or 2% per year from 1972-1977 to 1990-1994, from 14 to 22 per 100,000 among men and from 12 to 19 per 100,000 among women. The increases in rates were considerably more rapid for colon cancer, with rates approximately doubling, than they were for rectal cancer. Proximal colon cancer was more common than distal colon cancer over the whole study period, whereas rates for both cancers rose with similar annual percentage changes (> 5% per year) and across virtually all age groups. The estimated annual increases rose from 2% at ages 35-44 years to 7% at ages 75-84 years for proximal colon cancer, but they were more uniform for distal colon cancer (5-6% per year). Age-adjusted and age-specific rectal cancer rates changed little. The male:female age-adjusted rate ratio for colorectal cancer was 1.19 in 1990-1994. The ratios increased over time and varied by subsites, with ratios increasing from the proximal colon to the distal colon and to the rectum. Furthermore, men had higher rates than women for distal colon and rectal cancers at ages 55 and older, whereas women had higher rates than men at younger ages for these two cancers. Male:female rate ratios for proximal colon cancer did not vary substantially with age. The findings from this study indicate that subsite-specific incidence rates of colorectal cancer differ by sex and age and in their time trends. Cancers arising in the proximal colon, distal colon, and rectum may have somewhat different disease etiologies.     

Colorectal cancer incidence and survival among Alaska Natives, 1969-1993

BACKGROUND: Although colorectal cancer rates are low among most groups of Native Americans in North America, rates for Alaska Natives have been substantially elevated compared with US rates for all races combined. METHODS: To better describe the epidemiology of colorectal cancer incidence and survival among Alaska Natives, stratified by gender and tribal/ethnic affiliation, we examined data collected by the Alaska Native Cancer Registry 1969-1993. We calculated age-adjusted and age-specific incidence as well as actuarial survival rates, and examined histological type, site, stage at diagnosis, and treatment. We compared these data to colorectal cancer data from whites living in western Washington. RESULTS: In all, 587 colorectal cancer cases were identified among Alaska Natives over the 25-year period, for an age-adjusted annual incidence rate of 71.4/100000 in women, and 69.3/100000 in men. Compared to Alaska Indians, colon cancer rates were significantly higher in Aleuts (relative risk [RR] = 1.6, 95% CI: 1.2-2.2) and in Eskimos (RR = 1.5, 95% CI: 1.2-1.8), while rectal cancer rates did not differ by race/ethnicity. Alaska Natives experienced a 50% higher incidence rate of colorectal cancer overall compared to western Washington whites (RR = 1.5, 95% CI: 1.3-1.6), although rectal cancer rates were similar in the two populations. The highest RR were seen among Alaska Native women; Aleuts and Eskimos had colon cancer rates more than twice that of western Washington white women. No unusual qualitative features were found in the cancers occurring in Alaska Natives. Actuarial colorectal cancer survival rates for Alaska Natives overall were 74% at one year and 42% at 5 years; these rates were very similar to those observed for the western Washington population. Both one and 5-year survival rates showed a significant trend towards improvement over time. CONCLUSIONS: Alaska Natives had substantially higher colorectal cancer incidence rates compared to western Washington whites. Rates were particularly high for Aleut and Eskimo women. These data suggest a need for intensified secondary prevention strategies for this high-risk population, while further research is needed to identify modifiable risk factors.     

Descriptive epidemiology of vulvar and vaginal cancers in Vaud, Switzerland, 1974-1994

BACKGROUND: To analyse trends in incidence, survival and risk of second neoplasms following vaginal and vulvar cancers using data collected by the Swiss Cancer Registry of Vaud over the 21-year period 1974-1994. MATERIALS AND METHODS: Subjects were 257 vulvo-vaginal cancers. Of these, 69 were vaginal, 153 vulvar cancers, and 35 non-specified lower genital tract neoplasms; 94 in situ neoplasms were also registered (85 for the vulva). RESULTS: Invasive vaginal cancer incidence decreased from 0.8 in 1974-1984 to 0.4/100,000 women in 1985-1994, while invasive vulvar cancer incidence remained approximately stable around 1.2/100,000 (world standard); incidence of in situ vulvar cancer increased from 0.8 to 1.3/100,000, the rise being larger in younger women. Significant excesses for second primary neoplasms were observed for pro-pharyngeal and lung cancer, and for non-melanomatous skin neoplasms, as well as for invasive vulvar cancers following in situ cancers. CONCLUSIONS: This population-based dataset confirms that the incidence of in situ vulvar (but not invasive vulvar or vaginal cancer) has been increasing over the last 20 years. The excess second primary neoplasms supports the hypotheses that human papillomavirus and cigarette smoking are related to vulvo-vaginal neoplasms.     

Cutaneous gangrene secondary to metastatic calcification in end stage renal failure--a case report

The belief that oestrogens are involved in the pathogenesis both of testicular cancer in young men and of cancers of the endometrium and female breast has become widespread. In a search for possible hormonal links between these cancers, we investigated the cancer pattern in a cohort of women who had given birth to sons who developed testicular cancer. Particular focus, was given to oestrogen-related cancers. The present retrospective population-based cohort study is based on data from the Danish Cancer Registry. Mothers of 2,204 testicular-cancer patients were followed for the occurrence of cancer over a total of 70,063 person years. The ratio of observed cancers in the cohort over the expected numbers based on cancer incidence in the underlying female population served as measure of the relative risk (RR). The RR of developing breast cancer among mothers of testicular-cancer patients was 0.8 (95% confidence interval 0.6-1.1), the relative risk of endometrial cancer 0.6 (0.3-1.0) and of ovarian cancer 1.0 (0.6-1.6). Mothers of testicular-cancer patients are not at increased risk of developing oestrogen-related cancers.     

Risk of malignant neoplasms in patients with pulmonary sarcoidosis

BACKGROUND: For over 20 years the association between sarcoidosis and malignancy, particularly lymphoma and lung cancer, has been disputed with misclassification being the major concern. The aim of the present study was to analyse the incidence of malignancies in a cohort of patients with sarcoidosis by linkage to a nationwide population based cancer register. METHODS: The cohort comprised 254 patients followed for a median of 25 years until death, emigration, or 31 December 1992, whichever came first. The expected number of cancer cases was calculated using the annual age and sex specific cancer rates from the Danish Cancer Registry. RESULTS: Thirty six cancers were registered, three of which were misclassified as sarcoidosis, leaving 33 cancers compared with 23 expected (standardised incidence ratio (SIR) = 1.4; 95% CI 0.99 to 2.0). Five lung cancers were observed compared with 2.5 expected, yielding an SIR of 2.0 (95% CI 0.7 to 4.7). There was no incidence of lymphoma and only one case of leukaemia. There was a significant excess number of pharyngeal cancers based on two cases (SIR = 15.4; 95% CI 1.7 to 56). CONCLUSIONS: This study does not support the theory of an association between sarcoidosis and malignancy, and the main reason other studies have shown such an association is most likely to have been due to selection bias and misclassification.     

Genetic implications of double primary cancers of the colorectum and endometrium

Hereditary non-polyposis colorectal cancer (HNPCC) is an autosomal dominant condition predisposing to cancers of the colorectum and endometrium. Endometrial cancer is the most commonly occurring extracolonic cancer in HNPCC. Estimates of the cumulative incidence of endometrial cancer in women with mutations in the HNPCC genes range from 22-43%. In order to determine how frequently double primary cancers of the colorectum and endometrium are the result of a hereditary factor, we conducted a registry based study in Ontario and Quebec, Canada. We obtained pedigrees on 80 women diagnosed with double primary cancers of the colorectum and endometrium at less than 70 years of age. Family histories of cancer were obtained for all first degree relatives of these women and cancer rates were compared with age standardised provincial incidence rates in order to estimate the relative risks. There was a total of 82 cancers observed in relatives below the age of 55, compared with 31.2 expected, giving a relative risk of 2.6 (95% confidence interval (CI) 2.1-3.3). The relative risk for colorectal cancer below 55 was 16.1 (95% CI 11.6-21.8). This risk decreased with increasing age of onset of cancers in probands. For probands with both colorectal and endometrial cancer diagnosed under the age of 55, the relative risk of colorectal cancer in relatives below the age of 55 was 30.5 (95% CI 18.8-46.6). Similar patterns were observed for endometrial and pancreatic cancer. There were non-significant increases in rates of cancer of the oesophagus, stomach, small intestine, and bladder. There was no increased risk of breast cancer. The risk of lung cancer was decreased, especially in older relatives. Our findings indicate the presence of a significant genetic component of cancer in women with double primary cancers of the colorectum and endometrium.     

Survival rates for four forms of cancer in the United States and Ontario

OBJECTIVES: In this study, cancer survival rates for patients diagnosed in Ontario and selected areas within the United States were compared. METHODS: Relative survival rates were computed for patients aged 15 through 84 years diagnosed with any of four forms of cancer (breast, colon, lung, and Hodgkin's disease). The cohorts represented those diagnosed over the years 1978 through 1986 in the Canadian province of Ontario and in nine regions covered by the US National Cancer Institute's Surveillance Epidemiology and End Results program. Patients were followed through the end of 1990. RESULTS: The cumulative relative survival rates were similar for American and Canadian patients. The largest difference was observed for breast cancer, where patients in the United States enjoyed a survival advantage throughout the follow-up period. CONCLUSIONS: Patients in the United States and Ontario with the diseases studied, except for breast cancer, experience very similar survival. The greater use of mammographic screening in the United States could account for that country's higher breast cancer survival rate by promoting earlier and therefore more efficacious treatment, by introducing bias, or by a combination of both treatment and bias factors.     

Noncancer deaths in white adult cancer patients

BACKGROUND: The cancer-specific death rate is a commonly used indicator in the assessment of progress against cancer. However, since the cause of death is often not substantiated and complete medical information is lacking, the validity of cancer-specific mortality rates is being questioned. PURPOSE: We investigated the validity of the cancer-specific death rate by examining noncancer deaths of cancer patients in a large patient population. METHODS: Data were obtained from the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) Program on cancer patients diagnosed between 1973 and 1987, with follow-up complete through December 1987. The SEER database consists of 1.2 million records from nine population-based registries covering nine geographic regions of the United States. Rates of noncancer deaths in the U.S. population were obtained from the National Center for Health Statistics. Cancer mortality rates were subtracted from overall mortality rates to obtain noncancer death rates by sex and the 5-year age group for each calendar year. Excluded from the study were patients of races other than White and those diagnosed at age 85 years or more due to absence of noncancer death rate comparisons. Also excluded were cancer cases discovered at autopsy and in persons less than 20 years of age. The statistical analysis employed a log-linear model. RESULTS: The ratio of patient-to-general-population noncancer death rates, as calculated by dividing the number of patient noncancer deaths per year by the number found in the matched U.S. population data and referred to as the noncancer relative hazard, is considered significant with values greater than 1 for those with all cancers combined and for the common solid tumors examined. Of the 12 leading causes of death other than cancer in the patient population, the most common causes were circulatory and respiratory failures. The noncancer relative risk of death decreased rapidly after diagnosis and also decreased with the patient's age at diagnosis. It increased slightly with the calendar year of diagnosis. CONCLUSIONS: Because more noncancer deaths occurred shortly after diagnosis, it appears that this excess was caused by treatment of the cancer. Generally, cancer-specific death rates underestimate the mortality associated with a diagnosis of cancer. Therefore, because the degree of underestimation changes with time, an examination solely of cancer-caused mortality in assessing progress against the disease is incomplete.     

Multiple primary cancers in families with Li-Fraumeni syndrome

BACKGROUND: Li-Fraumeni syndrome is a dominantly inherited disorder characterized by early-onset breast cancer, sarcomas, and other cancers in children and young adults. Members of families with this syndrome also develop multiple primary cancers, but the frequency is unknown. To approach this issue, we quantified the incidence of second and third primary cancers in individuals from 24 Li-Fraumeni kindreds originally diagnosed with cancer during the period from 1968 through 1986. METHODS: The relative risk (RR) of subsequent cancers and 95% confidence intervals (CIs) were calculated by use of population-based incidence data from the Connecticut Cancer Registry. Kaplan-Meier analysis was used to determine the cumulative probability (+/- standard error) of subsequent cancers. RESULTS: Among 200 Li-Fraumeni syndrome family members diagnosed with cancer, 30 (15%) developed a second cancer. Eight individuals (4%) had a third cancer, while four (2%) eventually developed a fourth cancer. Overall, the RR of occurrence of a second cancer was 5.3 (95% CI = 2.8-7.8), with a cumulative probability of second cancer occurrence of 57% (+/- 10%) at 30 years after diagnosis of a first cancer. RRs of second cancers occurring in families with this syndrome were 83.0 (95% CI = 36.9-187.6), 9.7 (95% CI = 4.9-19.2), and 1.5 (95% CI = 0.5-4.2) for individuals with a first cancer at ages 0-19 years, 20-44 years, and 45 years or more, respectively. Thirty (71%) of 42 subsequent cancers in this group were component cancers of Li-Fraumeni syndrome. CONCLUSIONS: Compared with the general population, members of Li-Fraumeni syndrome families have an exceptionally high risk of developing multiple primary cancers. The excess risk of additional primary cancers is mainly for cancers that are characteristic of Li-Fraumeni syndrome, with the highest risk observed for survivors of childhood cancers. Cancer survivors in these families should be closely monitored for early manifestations of new cancers.     

Cancer incidence, mortality and survival: trends in four leading sites

Cancer mortality rates in the United States have stabilized in the past few years after rising for more than 50 years. Incidence and mortality rates for all cancers tend to be higher among men than women, among blacks than whites and among those over age 65. In 1994 cancer of the lung, prostate, breast, and colon/rectum (colorectal) will account for an estimated 57 percent of all new cancer cases and 55 percent of cancer deaths. Analysis of incidence, mortality and survival rates of these four major cancers indicate some encouraging trends. That is, even though age-adjusted incidence rates continue to increase, it appears that educational and screening efforts are having a positive influence on mortality rates. Lung cancer incidence has declined in recent years following a decrease in smoking among men that began some 20 years ago; evidence also indicates a start of a declining trend in their mortality from this disease, as well. Lung cancer incidence and mortality rates among women, however, continue to rise. In 1986 lung cancer became the leading cause of cancer deaths among women. Increased use and improved techniques of cancer detection for prostate, breast and colorectal cancers are resulting in larger numbers of these cancers being detected at early stages when they are more readily treatable. It is hoped that such activities will ultimately reduce mortality for these three major cancer sites.     

Aerosols: a re-emerging treatment

OBJECTIVE: To describe the variation in the use of radiotherapy (RT) in women in Ontario within 1 year of diagnosis of breast cancer, from 1982 to 1991, and to identify factors associated with these variations. DESIGN: Retrospective, population-based cohort study. SETTING: Ontario. POPULATION: All women registered by the Ontario Cancer Registry (OCR) with a diagnosis of invasive breast cancer between Jan. 1, 1982, and Dec. 31, 1991. INTERVENTIONS: RT to any anatomic site within 1 year of the diagnosis of breast cancer. OUTCOME MEASURES: Odds of receiving RT within 1 year of diagnosis (from RT files from all radiotherapy departments in Ontario) associated with year and with geographic, age-related and socioeconomic factors. RESULTS: Use of RT within 1 year of diagnosis increased from 21.1% (95% confidence interval [CI] 19.8-22.4) in 1982 to 44.7% (95% CI 43.4-46.0) in 1991 (p < 0.0001). Among the regions of Ontario, the use of RT varied from 24.5% (95% CI 23.5-25.6) to 44.4% (95% CI 43.0-45.9) (p < 0.0001). Increasing age was associated with decreasing likelihood of receiving RT (test for trend p < 0.0001), as was decreasing income (test for trend p < 0.0001). CONCLUSIONS: The use of RT within 1 year of the diagnosis of breast cancer in women in Ontario varies by region, age and income. Despite universal and comprehensive health insurance coverage, women with breast cancer in some populous regions of Ontario were less likely to receive RT within 1 year of their diagnosis than women in other populous regions.