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Biomedical subjects

A S Morrison

Publications and source records attributed to A S Morrison.

At least 55 records · Page 3Linked to original sources
PubMed1980

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.

Adult↗
PubMed1980

Basic issues in population screening for cancer.

The value of population screening as an approach to cancer control is controversial because the objectives, benefits, costs, and potential adverse effects of screening programs are not widely agreed upon, nor are the many difficulties involved in evaluating a cancer screening program well recognized. A review of the issues pertinent to cancer screening and their interrelationships is presented. The characteristics of a particular cancer that should be considered before it becomes the target of a screening program are described; emphasis is placed on the prevalence of the detectable preclinical phase. The features of a good screening test are reviewed and the importance of specificity is indicated. Methods for evaluation of screening programs are considered, and the need for measurement of the effects of screening on the mortality rate is emphasized. The biases inherent in some commonly used evaluation procedures, especially lead time bias and length bias, are discussed. The possible adverse effects of cancer screening are pointed out, especially its capacity to increase morbidity. Several approaches to improving cancer screening programs are presented. Finally, the relevance of knowledge regarding the optimum interscreening interval to cancer control and to research issues is described.

Age Factors↗
PubMed1980

An occupation and exposure linkage system for the study of occupational carcinogenesis.

Studies of the adverse effects of occupational exposures are most informative when jobs can be classified according to the specific chemical or physical agents involved. However, information sufficiently detailed to permit this is not often available. In such instances a study usually will be based on subjects classified according to industry or task, effectively ignoring the specific agents to which exposure occurred. Such crude classification tends to reduce or obscure associations between specific exposures and disease. In response to this problem, the authors have developed an occupation and exposure linkage system with particular reference to carcinogenesis. Occupations were classified by industry and by task within the industry. Lists of suspect carcinogens were developed and each suspect carcinogen was linked to industries and tasks in which it has been used. These links make it possible to place in the same exposure category all study subjects whose employment history suggests contact with a particular agent. Epidemiologic analysis then can be based on chemical and physical exposures, rather than on industries or tasks. The linkage system enhances the value of information on occupation obtained from death certificates, cancer registries, medical records, and questionnaires.

Amines↗
PubMed1979

Use of artificial sweeteners by cancer patients.

Current daily use of artificial sweeteners (AS) and diet drinks was evaluated for 1,862 patients hospitalized for cancer and for 10,874 "control" patients hospitalized for other conditions believed not to be associated with use of these substances. The data were derived from an ongoing survey in seven countries. For cancer of most sites, the age-standardized proportion of users of AS was somewhat less than that for controls. A greater proportion of users among cancer patients than among controls was noted only for cancer of the stomach among women. Little information on urinary tract cancer was available; there were no users of AS among 13 patients with cancer of the bladder, 5 with cancer of the renal pelvis, and 2 with cancer of the ureter. There were 455 cancer patients known to have been interviewed during their initial hospitalization for the disease. Based on these cases, an age-sex-country-standardized estimate of cancer incidence for users of AS, relative to nonusers, was 1.0. Only a very small proportion of patients reported daily use of diet drinks, and the proportion of users did not differ substantially between cancer patients and controls. The present data provide virtually no support for an overall positive association of AS with cancer.

Aged↗
PubMed1979

Lung cancer in young women.

A comparison was made between cigarette smoking histories of 31 women below age 50 years who had a diagnosis of lung cancer on hospital discharge and smoking histories of 124 women below age 50 years who had been hospitalized for other conditions. Of the women with lung cancer, 28 (90%) were current or former cigarette smokers; 72 (58%) of the comparison women were smokers. The relative risk estimate for lung cancer among smokers as compared with nonsmokers is 6.7, with 90% confidence limits of 4.0 and 11. Risk of lung cancer increased with the amount that the women smoked. The smokers with lung cancer had been smoking for longer periods than the smokers with other conditions. Assuming that the association is causal, cigarette smoking was responsible for about 77% of the lung cancer of young women in this survey.

Adult↗
PubMed1977

Oral contraceptives and hepatitis. A report from the Boston Collaborative Drug Surveillance Program, Boston University Medical Center.

History of oral-contraceptive use was compared between 68 women with a hospital-discharge diagnosis of acute hepatitis and 1142 women who had been admitted for other reasons to the same hospitals during the same period. The risk of admission to hospital for hepatitis for users of oral contraceptives was estimated to be 3-3 times that for non-users (95% confidence interval, 1-8--6-3). This overall association was almost entirely attributable to a strong association among women under 25 years of age. Among users of oral contraceptives, duration of use tended to be shorter for hepatitis patients than for controls.

Acute Disease↗
PubMed1977

Life cycle events in 15th century Florence: records of the Monte delle doti.

Records of a dowry investment fund operated by the city of Florence, Italy from 1425-1545 contain information on life cycle events of about 32,000 girls. This information includes date of birth, date and amount of investment, and date of dowry payment or death. In the present study, the first of 19 volumes of these records were used to compute death rates and payment rates (an approximation of marriage rates) and to analyze these rates according to age, time, and socioeconomic status. Usable records were obtained for 1631 girls. There were 315 deaths; death rates per 1000 person-years were 38, 17, 11, 16, and 19 for ages less than 5, 5-9, 10-14, 15-19, and 20+, respectively. Compared to previous and succeeding years, death rates increased 5-10 times in 1437-1438 and 1449-1450, years in which epidemics have been recorded. During these periods of epidemics, death rates were relatively low in the winter months. Death rate were made for 1274 girls. About three-fourths of these payments were made by age 20. Rate of payment increased with amount of investment. Proportionally, births were least frequent during December and January, indicating a deficit of conceptions around the time of Lent.

Adolescent↗
PubMed1976

Histologic specificity of the effect of age at birth of first child on breast cancer risk.

Slides of 531 breast cancers from Glamorgan, Wales, were classified according to the presence or absence of each of three histologic characteristics: stromal infiltration by linear strands of tumor cells, areas of intraductal carcinoma, and areas of lobular carcinoma in situ. The proportion of tumors with each of these characteristics was positively associated with age at first child-birth. Increasing age at first birth had a strong positive effect on the incidence risk of tumors with any of these features, but only a small effect on risk of tumors with none. For parous women, the rate of breast cancer with or without linear strands, with or without areas of intraductal cancer, and without areas of lobular carcinoma in situ was lower than for nulliparous women. Parity appeared not to reduce the risk of tumors with areas of lobular carcinoma in situ.

Adult↗
PubMed1976

Some international differences in treatment and survival in breast cancer.

In a recent study, 5-year survival rates for breast cancer patients in Boston (Massachusetts), Glamorgan (Wales), Slovenia (Yugoslavia) and Tokyo (Japan) were 57.3%, 49.5%, 41.9% and 74.9%, respectively. In this report, data are presented on the types of treatment used in the four areas and on the relationship of differences in treatment practices to the differences in survival rates. Generally, surgically treated patients who also had radiotherapy had lower survival rates than patients in the same area who had similar operations without radiotherapy. In each area, the survival rate was higher for patients who had radical mastectomy than for those who had simple mastectomy. The Japanese patients had the highest survival rate within nearly every treatment and extent-treatment category. Thus, the high survival rate of these patients was not explained by the variables considered. Survival differences between Boston, Glamorgan and Slovenia were largely explained by differences in extent of disease and type of treatment. As the nature of the treatment--survival trends was consistent with the interpretation that treatment tended to be selected according to apparent prognosis, the degree to which treatment customs were determinants of the differences in survival rate among the three areas is uncertain.

Boston↗
PubMed1976

Cryptorchidism, hernia, and cancer of the testis.

Risk of cancer of the testis was related to nondescent and hernia in a comparison of 596 testicular cancer patients and 602 unaffected men who had been in active service in the U.S. Army between 1950 and 1970. Medical histories were obtained from routine service records. Undescended testis was associated with a testicular cancer risk 8.8 times that of normal. Among cancer patients with a history of undescended testis, seminomas were nearly twice as frequent as in the remaining patients. Of 14 patients with unilateral undescended testis, 12 had the tumor on the side of the defect. Testicular cancer risk was estimated to be 2.9 times higher in men who had reported having had an inguinal hernia than in those who had not. Side of hernia and side of tumor were not associated; histologic type was not related to history of hernia.

Cryptorchidism↗
PubMed1976

Some social and medical characteristics of Army men with testicular cancer.

Risk of developing cancer of the testis was related to social and medical characteristics in a case-control study of men on active duty in the US Army, 1950-1970. Service records were obtained for 702 newly-diagnosed patients and 624 members of a systematic sample of unaffected servicemen. Risk ratios were computed for seminomas, tumors of other histologic types, and for all tumors combined. Respectively, these risk ratios were 0.3, 0.1 and 0.2 for blacks compared to whites, 1.5, 1.1 and 1.3 for Protestants compared to Catholics, and 1.5, 1.0 and 1.2 for the ever married compared to the never married. Risk increased regularly with duration of schooling for seminomas but not other types of tumors. Risk appeared relatively low for men from large sibships. Men from the North Central or Western parts of the country were at higher risk than those from the South or Northeast, a trend that was stronger for tumors other than seminomas. Observed changes in risk with respect to history of mumps and ABO blood group were small.

Adult↗