Alan S. Morrison

An International Study of Smoking and Bladder Cancer

The effects of smoking cigarettes and other forms of tobacco on the development of cancer of the lower urinary tract (bladder cancer) were evaluated in Boston, Massachusetts, Manchester, United Kingdom and Nagoya, Japan. Population-based series of incident cases and controls were identified and interviewed in each area. The present analyses were based on 592 cases and 533 controls in Boston, 553 cases and 731 controls in Manchester, and 290 cases and 588 controls in Nagoya. Smokers of cigarettes had about twice the incidence of bladder cancer as nonsmokers. In men the strength of the association between cigarette smoking and bladder cancer was similar in the 3 study areas. The strength of the association varied somewhat from area to area among women. Bladder cancer risk increased with frequency of cigarette smoking and with deep inhaling. In Boston men who smoked 2 or more packs of cigarettes per day and inhaled deeply had nearly 7 times the risk of nonsmokers. Ex-smokers had a level of risk between that of current smokers and nonsmokers. However, there was no clear relationship between risk and age at which cigarette smoking began, time since discontinuation among ex-smokers and use of filters. Over-all, there was little difference in bladder cancer risk between men who had and who had not smoked pipes but pipe smoking did appear to be associated with risk among men who had never smoked cigarettes. Cigar smoking was unrelated to bladder cancer.

Artificial Sweeteners and Cancer of the Lower Urinary Tract

We evaluated the relation between cancer of the lower urinary tract and the use of artificial sweeteners in a case-control study of 592 patients with lower-urinary-tract cancer (94 per cent of whom had a bladder tumor) and 536 controls chosen from the general population of the study area. A history of use or artificial sweeteners and exposure to other known or suspected risk factors was determined by interview. In those who had used dietetic beverages and in those who had used sugar substitutes, the relative risk of lower-urinary-tract cancer was estimated as 0.9 (0.7 to 1.2, 95 per cent confidence interval), as compared with 1 in nonusers of artificial sweeteners. Among men, the relative risk was 0.8 (0.6 to 1.1) in those who had used dietetic beverages and 0.8 (0.5 to 1.1) in those who had used sugar substitutes. Among women, the corresponding relative risks were 1.6 (0.9 to 2.7) and 1.5 (0.9 to 2.6). Increasing frequency of duration of use of artificial sweeteners was not consistently associated with increasing relative risk. This study suggests that, as a group, users of artificial sweeteners have little or no excess risks of cancer of the lower urinary tract.

Relationship between mammographic and histologic features of breast tissue in women with benign biopsies

Mammograms and histologic slides of a group of 320 women who had breast symptoms and a biopsy without cancer being found were reviewed. The mammographic features assessed were the parenchymal pattern and extent of nodular and homogeneous densities. In addition to the pathologic diagnosis, the histologic features assessed included epithelial hyperplasia and atypia, intralobular fibrosis, and extra‐lobular fibrosis. Among premenopausal women, those with marked intralobular fibrosis were more likely to have large (3+ mm) nodular densities on the mammogram. Among postmenopausal women, epithelial hyperplasia or atypia was related to having nodular densities in at least 40% of the breast volume. In both groups, marked extralobular fibrosis was related to the presence of homogeneous density on the mammogram. We conclude that mammographic nodular densities may be an expression of lobular characteristics, whereas homogeneous density may reflect extralobular connective tissue changes.

Incidence risk factors and survival in breast cancer: Report on five years of follow-up observation

Abstract In a previous report three year survival rates in breast cancer were related to geography, socio-economic status and age at first pregnancy. Here, results from 5 years of follow-up observations are summarized with respect to incidence risk factors. Age-adjusted 5 year survival rates were 57·3% in Boston, Massachusetts, 49·5% in Glamorgan, Wales, 41·9% in Slovenia, Yugoslavia, and 74·9% in Tokyo, Japan; corresponding age-adjusted annual incidence rates per 100,000 were 55·0, 38·8, 24·4 and 12·9 . Although survival rates varied markedly among these areas, there was not a consistent relationship between incidence rate and probability of survival. Differences in survival rates between Boston, Glamorgan and Slovenia were reduced when examined according to extent of disease at diagnosis, but the relatively high survival rate in Tokyo was not explained. Survival rates tended to increase, although inconsistently, with increasing socioeconomic status as measured by duration of schooling. Probability of survival was not related to childbearing or, for parous patients, to age at first full-term birth.

Histologic and mammographic specificity of risk factors for benign breast disease

This study evaluates the effects of potential risk factors for benign breast disease (BBD) with special attention to the histologic and mammographic specificity of the effects. Cases were 172 women with BBD that underwent biopsy; controls were 134 women free of breast signs or symptoms. All cases and controls had undergone mammography. For all types of BBD combined, parity, use of oral contraceptives, and use of exogenous estrogen after menopause were strongly protective, whereas obesity and early menarche were weakly protective. Family history of breast cancer was virtually unrelated to BBD. The protective effect of parity was stronger for BBD with intralobular or extralobular fibrosis, and with mammographic homogeneous density or large nodular densities, than it was for BBD without these characteristics. Similar relations with the histologic and mammographic features were observed for obesity. These findings suggest that some risk factors for BBD have effects that are related to specific features of its morphology.

Epidemiology and environmental factors in urologic cancer.

Urologic cancers include malignancies of the genital and the urinary organs of men, and the urinary organs of women. For men in the United States, urologic cancers account for about 25% of all new cases of cancer and about 15% of cancer deaths. For women, cancers of the urinary organs account for 4% of all new cases of cancer and 3% of cancer deaths. Of urologic cancers, bladder cancer has been the most intensively studied epidemiologically. Cigarette smoking is the most important known preventable cause of the disease. Occupational exposures continue to come under suspicion. It appears that neither coffee drinking nor use of artificial sweeteners are important risk factors. Current questions in the etiology of prostate cancer concern its relationships to benign prostatic hypertrophy, to components of the diet and to hormone metabolism. Little is known of the etiology of kidney cancer other than probable associations of the disease with cigarette smoking and exposure to asbestos. Testicular cancer is associated with undescended testis and possibly other urogenital anomalies. The relationships of testicular cancer to pesticide exposure, in utero estrogen exposure, and infection are current research issues.

Geographic and time trends of coffee imports and bladder cancer

Abstract Bladder cancer incidence rates were related to per capita coffee imports for ten countries and time trends in these variables were analyzed for the United States and Denmark. Among the ten countries, there was a weak positive association between coffee and bladder cancer for both men and women. There was a weak positive correlation of the time trends of coffee imports and bladder cancer incidence for men, but not women, in the United States. The trend of coffee imports for Denmark was dissimilar to both male and female trends in bladder cancer incidence. Because the relationships observed are neither strong nor consistent in direction, these results provide little support for an association of coffee drinking with the development of bladder cancer.