Geographical patterns in morbidity for carcinoma of the trachea, bronchus, and lung in Canada during the period 1976–1980

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tality data are not enough to measure the dimensions of this cancer due to improper recording and diagnosis. The present study uses pathological material as a source of information. The first part of the study covers the years 1968-1972 during which 7585 biopsies were performed with 996 proving to be malignant, i.e., 13.13% with 56.22% of the total malignancies or 7.38% of the total biopsies occurring in males and 43.77% of the total malignancies or 5.75% of the total biopsies in females. Bronchogenic carcinoma formed 1.41% of the total malignancies or 0.18% of the total biopsies. The second part covers the years 1973-1977 during which 20863 biopsies were performed. 1940 proved to be malignant, i.e. 9.30% with 54.02% of the total malignancies or 5.02% of the total biopsies occurring in males and 49.98% of the total malignancies and 4.28% of the total biopsies in females. Bronchogenic carcinoma formed 5.46% of the total malignancies or 0.51% of the total biopsies. The third part covers the years 1978-1982 during which 16530 biopsies were performed. 2301 proved to be malignant, i.e. 1392% with 60.76% fo the total malignancies or 8.46% of the total biopsies occurring in males and 39.24% of the total malignancies or 5.46% of the total biopsies in females. Bronchogenic carcinoma formed 5.0% of the total malignancies or 0.7% of the total biopsies. Bronchogenic carcinoma occurred more frequently in males with a mean ratio of 8.4:1. Epidermoid carcinoma was the com2aonest histological type encountered. Other interesting data are discussed in the text including age, sex, habits, socioeconomic status, diagnostic methods etc. Geographical Patterns in ~ r b i d i t y for Carcinoma of the Trachea, Bronchus, and Lung in Canada During the Period 19761980. Ayiomamitis, A., Badawi, I. Department of Preventive Medicine and Biostatistics, Faculty of Medicine, University of Toronto, Toronto. Lung cancer is the number one cause of death in Canadian males aged 35-84 (for all five-year age groups) and the second or third leading cause of death in Canadian women aged 35-74 (for all five-year age groups). In order to assess the geographical variability in morbidity from this disease, incidence figures for carcinoma of the trachea, bronchus and lung were collected from the publications of Statistics Canada for the period 19761980 for nine of the ten Canadian provinces (Ontario was excluded as data is not currently available). All rates were standardized to the 1971 Canadian population for

age and sex using the direct method. Standard errors of age-standardized morbidity rates (ASMR) were computed using Chiang's method (1961). Male rates in the Eastern (Nova Scotia, Prince Edward Island, Newfoundland) and Western (Saskatchewan, Alberta, British Columbia) regions of the country are the lowest, ranging from 32-58 and 32-57 new cases per year per i00,000 population, respectively, while those in the central region (Manitoba, Quebec, New Brunswick) are the highest at 50-69 new cases per year per i00,000 population. Rates for females were comparable across all three regions (4-16, 11-23, and 9-21 new cases per year per i00,000 population). Significant differences in geography, climate, and population characteristica between these regions may account for these drastic differences. Secular Trends in Lung Cancer Morbidity in Canada for the Period 1970-1980. Ayiomamitis, A., Badawi, I. Department of Preventive Medicine and Biostatistics, Faculty of Medicine, University of Toronto, Toronto. Lung cancer is the number one cause of death in Canadian males aged 35-84 (for all five-year age groups) and the second or third leading cause of death in Canadian women aged 35-74 (for all fiveyear age groups). In order to assess the longterm morbidity of this disease, incidence figures for carcinoma of the trachea, bronchus and lung were collected from thepublications of Statistics Canada for the period 1970-1980. All rates were standardized to the 1971 Canadian population for age and sex using the direct method. Standard errors of age-standardized morbidity rates (ASMR) were computed using Chiang's method (1961). Morbidity from lung cancer has been increasing at a drastic pace for both males and females during this period - the ASMR has risen by 46% and 151% for males and females, respectively, since 1970. As dramatic is the divergent difference between male and female ASMR's - the male ASMR was 5.8 times that of the female ASMR in 1970 and, by 1980, the difference had declined by 40% to a ratio of 3.4. It appears that factors other than changes in the classification and reporting practices are responsible for the substantial increase in lung cancer morbidity during this relatively short period, particularly as it relates to women. Recent trends towards increased consumption of tobacco products may account for the drastic increase in the female rates. Geographical Patterns in Mortality from Carcinoma o£ the Trachea, Bronchus, and Lung in Canada During the Period 1976-1980. Ayiomamitis, A., Badawi, I. Department of Preventive Medicine and Biostatistics, Faculty of Medicine, University of Toronto, Toronto, Canada M5S IA8. Lung cancer is the number one cause of death in Canadian males aged 35-84 (for all five-year age groups) and the second or third leading cause of death in Canadian women aged 35-74 (for all five-