Showing papers by "Cancer Epidemiology Unit published in 1992"

Breast Cancer In Men: Risk Factors with Hormonal Implications

Abstract: Cases included in a population-based case-control study of breast cancer in men were recruited from 10 geographic areas of the United States from 1983 to 1986. Controls, matched to cases on age and geographic area, were selected by random digit dialing for men under age 65 years and from Health Care Financing Administration files for older men. Results are based on responses from 227 cases and 300 controls to questions asked in a standardized personal interview. An increased risk of breast cancer was most strongly associated with undescended testes and was also related to orchiectomy, orchitis, testicular injury, late puberty, and infertility; and a decreasing trend in risk was observed with an increasing number of children. Relative risk estimates were also elevated in relation to a history of high blood cholesterol, rapid weight gain, benign breast conditions, and possibly obesity. These findings suggest that breast cancer in men develops in response to androgen deficiency associated with testicular dysfunction and under conditions associated with excess estrogen. Risk was also found to be elevated in men with a history of amphetamine use, diabetes, and cigar smoking and reduced in men with prior head trauma.

Familial testicular cancer: a report of the UK family register, estimation of risk and an HLA class 1 sib-pair analysis.

Abstract: Forty-two families with two or more cases of testicular cancer have been reported to the UK Register for Familial Testicular Cancer, comprising two pairs of identical twins, 27 sets of other brothers (25 pairs, two triples), nine father-son pairs, two pairs of first cousins and two uncle-nephew pairs. In total 91 testicular tumours are described in 86 individuals (42 (46%) pure seminoma, 49 (54%) other germ cell tumours). The median age at diagnosis in these patients was significantly younger than that in a comparable series of non-familial patients (29 c.f. 32.5 years, P less than 0.01). In a case-control comparison of 794 testicular cancer patients, eight patients (1.0%) had a brother and four patients (0.5%) had a father with a previous diagnosis of testicular cancer at the time of their own diagnosis (and these families are all included in this report). Two out of 794 controls (0.3%) had a first degree relative with testicular cancer. The cumulative risk to a brother of a patient for developing testicular cancer by the age of 50 years was estimated to be 2.2% (95% C.I. 0.6-3.8%) which results in a relative risk of 9.8 (95% C.I. 2.8-16.7) in comparison with the general population. HLA Class I typing of 21 affected sib-pairs demonstrated four (19%) sharing two haplotypes, 13 pairs (62%) sharing one and four pairs (19%) sharing none. This did not differ significantly from the expected proportions of 25%/50%/25%. It is unlikely, therefore, that there is a major gene associated with testicular cancer predisposition within or closely linked to the major histocompatibility gene complex on chromosome 6.

Preterm delivery, low birthweight and small-for-gestational-age in liveborn singleton babies resulting from in-vitro fertilization

Abstract: The Medical Research Council In-Vitro Fertilization (IVF) Register report on births resulting from assisted conception in Great Britain demonstrated a high incidence of preterm and low birthweight babies. This incidence remained high even when the analysis was restricted to singleton babies. The present paper investigates possible risk factors for prematurity, low birthweight and small-for-gestational-age (SGA) in singleton IVF births. Thirteen per cent of singleton IVF babies were preterm, 11% low birthweight and 17% small-for-gestational-age. Analysis by multiple regression indicated that hypertension during pregnancy was an independent risk for preterm delivery, low birthweight and SGA, bleeding during pregnancy for preterm delivery, and the number of embryos transferred and the type of infertility for low birthweight.

Alcoholism and cancer risk: a population-based cohort study.

Abstract: The incidence of cancer was studied in a population-based cohort of 9,353 individuals (8,340 men and 1,013 women) with a discharge diagnosis of alcoholism in 1965-83, followed up for 19 years (mean 77) After exclusion of cancers in the first year of follow-up, 491 cancers were observed cf 3432 expected through 1984 (standardized incidence ratio [SIR] = 14, 95 percent confidence interval [CI] = 13-16) A similar excess risk of cancer was seen among men (SIR = 14, CI = 13-16) and among women (SIR = 15, CI = 11-20) We observed the established associations with cancers of the oral cavity and pharynx (SIR = 41, CI = 29-57), esophagus (SIR = 68, CI = 45-99), larynx (SIR = 33, CI = 17-60), and lung (SIR = 21, CI = 17-26), although confounding by smoking likely increased these risk estimates While there was evidence of increased risk for pancreatic cancer (SIR = 15, CI = 09-23), alcoholism did not elevate the incidence of cancer of the stomach (SIR = 09, CI = 6-14), large bowel (SIR = 11, CI = 08-15), prostate (SIR = 10, CI = 08-13), urinary bladder (SIR = 10, CI = 06-15), or of malignant melanoma (SIR = 09, CI = 03-19) Among women, the number of breast cancers observed was close to expected (SIR = 12, CI = 06-22), although a significant excess number of cervical cancers occurred (SIR = 42, CI = 15-91)(ABSTRACT TRUNCATED AT 250 WORDS)

Alcoholism and liver cirrhosis in the etiology of primary liver cancer.

Abstract: The aim of this study was to determine the risk of developing primary liver cancer in patients with a diagnosis of alcoholism, liver cirrhosis, or both. Three population-based, mutually exclusive cohorts were defined on the basis of hospital discharge diagnoses between 1965 and 1983. Complete follow-up through 1984—excluding the first year of follow-up—showed that among 8,517 patients with a diagnosis of alcoholism, 13 cancers occurred, vs. 4.2 expected (standardized incidence ratio (SIR) = 3.1; 95% confidence interval (CI) = 1.6 to 5.3); among 3389 patients with liver cirrhosis, 59 cancers occurred, vs. 1.7 expected (SIR = 35.1; 95% CI = 26.7 to 45.3), and among 836 patients with both diagnoses, 11 cancers occurred, vs. 0.3 expected (SIR = 34.3; 95% CI = 17.1 to 61.3). Thus, alcoholism alone entailed a moderately increased risk and alcoholism with liver cirrhosis did not increase the high relative risk for liver cancer more than cirrhosis alone. We conclude that alcohol intake may be a liver carcinogen only by being causally involved in the development of cirrhosis; and further, that the risk of developing liver cancer following cirrhosis in this population is similar to or higher than that after chronic hepatitis-B-virus infection in other Western countries.

Trends in childhood leukaemia in the Nordic countries in relation to fallout from atmospheric nuclear weapons testing.

Abstract: OBJECTIVE--To obtain further information about the risks of childhood leukaemia after exposure to ionising radiation at low doses and low dose rates before or after birth or to the father9s testes shortly before conception. DESIGN--Observational study of trends in incidence of childhood leukaemia in relation to estimated radiation exposures due to fallout from atmospheric nuclear weapons testing during the 1950s and 1960s. SETTING--Nordic countries. SUBJECTS--Children aged under 15 years. MAIN OUTCOME MEASURES--Incidence rates of leukaemia by age at diagnosis, sex, country, and calendar year of diagnosis or year of birth; exposure category; relation between leukaemia and exposure for children aged 0-14 and 0-4 separately. RESULTS--During the high fallout period the average estimated dose equivalent to the fetal red bone marrow was around 140 mu Sv and the average annual testicular dose 140 mu Sv. There was little evidence of increased incidence of leukaemia among children born in these years. Doses to the red bone marrow of a child after birth were higher, and during the high exposure period children would have been subjected to an additional dose equivalent of around 1500 mu Sv, similar to doses received by children in several parts of central and eastern Europe owing to the Chernobyl accident and about 50% greater than the annual dose equivalent to the red bone marrow of a child from natural radiation. leukaemia incidence and red marrow dose was not related overall, but rates of leukaemia in the high exposure period were slightly higher than in the surrounding medium exposure period (relative risk for ages 0-14: 1.07, 95% confidence interval 1.00 to 1.14; for ages 0-4: 1.11, 1.00 to 1.24). CONCLUSIONS--Current predicted risks of childhood leukaemia after exposure to radiation are not greatly underestimated for low dose rate exposures.

Twin Membership and Breast Cancer Risk

Abstract: Pregnancy estrogens are substantially elevated in twin pregnancies and are likely to be more so in the case of dizygotic twins. If levels of pregnancy estrogens were positively related to breast cancer risk in the offspring, female twin members would be expected to be at slightly higher risk. Data from an international case-control study were utilized to assess this hypothesis. The analysis was based on 870 cases with breast cancer and 2,641 hospital controls from two sites: Glamorgan, Wales (1965-1967), and Boston, Massachusetts (1965-1966). Seventeen cases were members of twin pairs, and 8 of them had a twin brother; 33 controls were members of twin pairs and 14 had a twin brother. Among all women, the odds ratios for breast cancer were as follows: for twins with brothers, 1.54 (95% confidence interval (CI) 0.64-3.71); for twins with sisters, 1.30 (95% CI 0.58-2.92); and for all twins, 1.40 (95% CI 0.77-2.55). The odds ratios were higher among premenopausal women. These findings are not conclusive, but they are compatible with the hypothesis that pregnancy estrogens may affect the risk of breast cancer in the offspring.

Variation and Covariates of the Number of Benign Nevi in Adolescents

Abstract: Melanocytic nevi of diameter greater than or equal to 2 mm were counted on most of the skin surface of 349 adolescents aged 14-15 years of European race or ethnicity in Dunedin, New Zealand. Total counts are described by means of a form of Poisson-error log-linear modeling suitable for data showing unexplained variation (NE Breslow, Appl Statist 1984;33:38-44). There were marked interpersonal variation in the number of nevi; only some was attributable to observed factors. The mean and median counts were 23.8 and 18 nevi, respectively. The estimated ratio of the number of nevi for females compared with males was 0.7 (95% confidence interval (CI) 0.6-0.8). Greater amounts of sunbathing were associated with greater numbers of nevi. Hair and eye color, socioeconomic status, and sunburn history did not show statistically significant effects. Time since menarche and shaving status also showed no effects. Lack of suntan was associated with lower counts. Freckling was positively correlated with higher counts; the severe freckling group had an estimated ratio of 1.9 (95% CI 1.3-2.8) compared with those with no or very few freckles. The results are consistent with the hypothesis that ultraviolet radiation exposure from recreational sun exposure positively influences the total burden of nevi in normal subjects. Comparison with other epidemiologic studies suggests that the typical ultraviolet radiation dose-nevus yield curve might be steeper in males than females. Unexplained variation of nevus count may reflect heterogeneity of constitutional factors not yet measured in epidemiologic studies.

Effects of Different Designs and Extension of a Food Frequency Questionnaire on Response Rate, Completeness of Data and Food Frequency Responses

Abstract: The authors studied how the introduction of several modifications to a basic food frequency questionnaire can influence the results of dietary surveys. Modifications covered eight combinations based on three levels: increasing versus decreasing order of frequency categories; questionnaires without versus with questions about portion sizes, and questionnaires without versus with extra non-dietary questions. The sample included 6783 women between the ages of 40 and 70 years who took part in mammography screening. The women were randomly assigned to one of the eight study groups. All of the women in each group received one of the eight differently modified questionnaires. The forms extended in length by extra non-dietary questions and portion size categories resulted in a 20% higher total non-response compared to the shorter basic form. Partial non-response was significantly lower for all four questionnaire types that included portion sizes. When portion sizes were included in the questionnaire, the reported mean frequency of consumption was significantly reduced for fat (-10 times per month), milk (-6), bread (-5), vegetables (-2) and fish (-0.4). The decreasing order of responses to the frequency categories was associated with a statistically significant increase in the frequency responses for bread (2.6 times per month), vegetables (2) and fish (0.6). These data provide evidence that the design and extension of food frequency questionnaires influence the results of dietary studies.

Adolescence and sun protection.

Abstract: AIM to examine adolescents' sun behaviours and use of sun protection measures, attitudes to tanning, and awareness of melanoma, in the light of the Cancer Society's Sun-smart campaign in the summer of 1990-1. METHODS a sample of 345 fourth formers from schools in Auckland, Wellington and Christchurch was surveyed regarding their experiences and beliefs about tanning, and their use of sun protection measures including sunblock lotions, hats and clothing; their knowledge of melanoma and risks for melanoma; and their exposure to the educational campaign and its message. RESULTS despite relatively high awareness of melanoma as a dangerous form of cancer, a significant proportion of the sample showed high positive attitudes towards tanning and high levels of sun exposure without adequate sun protection. On the positive side, reports of exposure to sources of information about melanoma were correlated with melanoma awareness, which in turn predicted use of sun protection measures. CONCLUSION the findings suggest that campaigns such as those of the Cancer Society have an important role to play in reducing high levels of sun exposure among adolescents. Continued efforts need to be directed at adolescents to increase the acceptability and use of sun protection measures.

Erythrocyte sedimentation rate as a tumor marker in human prostatic cancer. An analysis of prognostic factors in 300 population-based consecutive cases

Abstract: Background. The natural history of prostatic cancer is variable. Our knowledge of prognostic factors is limited; therefore, research is needed. Methods. The cases of 300 population-based consecutive patients with a diagnosis of cancer of the prostate were analyzed regarding different prognostic factors (but with special reference to the erythrocyte sedimentation rate [ESR]). Results. After a mean observation time of 100 months, M category, ESR, grade, performance status, hemoglobin level, and T category were found to correlate with disease-specific death using multivariate analysis. The variables correlating with progression in the multivariate model were M category, ESR, T category, grade, treatment, and age. Patients treated with estrogen had a significantly lower risk (relative hazard, 0.3) of relapse. ESR was highly statistically significant (P < 0.0001) as a prognostic factor. With the variable in linear form, a 20-mm/h higher level suggested a 29% increased risk, on average, for dying of prostatic cancer (using a best-fit multivariate model). However, the relationship was not linear. After correcting for the effect of other factors, the risk for dying of prostatic cancer was lowest when the ESR was 40–50 mm/h and highest when its values were highest. Conclusions. ESR is an indicator of increased risk of progression and death in prostatic cancer. Other prognostic factors such as M and T categories, grade, performance status, hemoglobin level, and age currently are more important when planning treatment. It is possible that the ESR reflects aspects of tumor-host relationship and that both a low and high ESR are markers for patients with receding host defence mechanism.

Occupation and bladder cancer: a death-certificate study.

Abstract: Occupational statements on death certificates of 2,457 males aged 25-64 who died from bladder cancer in selected coastal and estaurine regions of England and Wales during 1965-1980 were studied. Excess mortality was found for deck and engine room crew of ships, railway workers, electrical and electronic workers, shoemakers and repairers, and tobacco workers. An excess of cases also occurred among food workers, particularly those employed in the bread and flour confectionary industry or involved in the extraction of animal and vegetable oils and fats. Use of a job-exposure matrix revealed elevated risk for occupations in which most workers were exposed to paints and pigments, benzene and cutting oils.

Maternal and perinatal risk factors for Wilms' tumor : a nationwide nested case-control study in Sweden

Abstract: This report describes maternal and perinatal risk factors for Wilms' tumor analyzed in a case-control study nested in a nationwide cohort in Sweden. The Swedish National Cancer Registry ascertained ...

Trends in childhood and adolescent cancer survival in Sweden 1960 through 1984.

Abstract: The temporal changes in childhood and adolescent cancer survival in Sweden 1960–1984 were analyzed. Complete follow-up through 1986 of 6 262 patients younger than 20 years at diagnosis revealed that the overall 5-year survival rates increased from 36.1 to 65.7% in males and from 43.6 to 73.6% in females. The temporal trends differed markedly between age groups and tumour sites and types. Over the study period, 5-years, survival for testicular cancer increased from 46.9 to 87.2%, kidney cancer, predominantly Wilms' tumour from 35.5 to 77.1% (with a higher rate of 89.1% in 1975–1979), Hodgkin's disease from 61.2 to 91.9%, non-Hodgkin's lymphoma from 32.5 to 76.6%, and all leukemias from 8.9 to 58.7%. Only a moderate improvement was noted for tumours of the bone, muscle and connective tissue, and survival rates for tumours of the nervous system remained largely unchanged. Our data reflect the remarkable therapeutic improvements that have occurred for cancer in the young and indicate that these improvements h...

Raised thyroid stimulating hormone associated with kelp intake in British vegan men

Abstract: To explore the hypothesis that the iodine intake of vegans might be inadequate, thyroid stimulating hormone concentrations were measured in plasma samples from 101 British men, of whom 48 were vegans and 53 were omnivores. The geometric mean thyroid stimulating hormone concentration, adjusted for age and body mass index, was 47% higher in the vegans than in the omnivores (P= 0.001). Five vegans but none of the omnivores had a thyroid stimulating hormone concentration above the reference upper limit of 5 mU/1 (P=0.022). High concentrations of thyroid stimulating hormone are usually indicative of marginal iodine status, but can also result from excessive iodine intake. The three vegans with the highest values of thyroid stimulating hormone reported regular use of kelp tablets or kelp powder. None of the other vegans, and none of the omnivores, reported taking kelp. After exclusion of the three vegans who took kelp, the remaining vegans had an adjusted geometric mean thyroid stimulating hormone concentration 29% higher than that of the omnivores (P=0.012). It was concluded that use of kelp can be associated with raised thyroid stimulating hormone, and that the iodine status of vegans who do not use kelp requires further investigation.

Reduced risk of hip fracture in women with endometrial cancer.

Abstract: The effect of excessive endogenous oestrogens on the risk of hip fracture was investigated in a population-based cohort of 2111 women with endometrial carcinoma who were followed up from age 50 years regarding the occurrence of a first hip fracture. Overall, 77 cases of hip fracture were observed, as against 120.8 expected, which meant a significantly reduced relative risk, standardized incidence ratio (SIR) = 0.6, 95% confidence interval (CI): 0.5-0.8. This possible protective effect was significant for cervical fractures, SIR = 0.6 (95% CI: 0.4-0.8), but not for trochanteric, SIR = 0.8 (95% CI: 0.5-1.1). Age at endometrial cancer diagnosis was not a determinant of the risk of hip fracture. A lowered relative risk was present regardless of age at diagnosis and persisted during the entire follow-up period and into advanced ages. A case-control analysis within the cohort, and based on medical record data, indicated that a higher weight might be associated with a greater protective effect, as compared with a lower weight. Exposure to exogenous oestrogens was infrequent and could not have explained the present results. We conclude that persistent influence of oestrogens, notably of endogenous origin, can reduce the risk of hip fractures, and that this protective effect may be long-lasting and extend to advanced ages.

Sex hormones and cancer.

Abstract: There are few instances in which a clear effect of hormones on cancer risk is known and in which the effects of those hormones on the cells concerned are also known. The best examples are the relationships between sex hormones and cancer in women. The effects of sex hormones both on the risk for endometrial cancer and on the cells of the endometrium are well understood, and the evidence strongly suggests that hormones act by altering the rate of cell division. The same mechanism may explain the relationships between sex hormones and the risk for breast cancer, but our understanding of cancers at this site is incomplete. Less still is known about the mechanisms of the effects of sex hormones on other hormone-related cancers, such as those of the ovary and cervix. Most sex hormones are not genotoxic.

Long-term consequences of estrogen and estrogen-progestin replacement.

Abstract: Except for the control of smoking, hormone replacement therapy (HRT) is potentially one of the most useful means of preventing major causes of morbidity and mortality in older women, who are likely to spend more than one-third of their lives in a postmenopausal (estrogen-deficient) stage. A full assessment of the overall long-term effects of noncontraceptive estrogens—with and without cyclically added progestins—therefore is needed urgently. This paper briefly reviews the available epidemiologic findings to date, with emphasis on a prospective study in Uppsala, Sweden. An increase in the risk of endometrial cancer which is substantially dependent on dose and duration of the exposure has been established, whereas a biologically plausible protective effect of progestins has been documented in only a few studies. A moderate, perhaps twofold, increase in the incidence of breast cancer has been found in several recent studies, notably among long-term and/or current users of potent estrogens; there is no evidence that progestins counteract this adverse effect. The risk of osteoporotic hip fractures can be reduced substantially, at least during ongoing treatment starting early after menopause. A 25 to 50 percent reduction in cardiovascular morbidity and mortality has been shown consistently and might outweigh any conceivable adverse effect of HRT. Notwithstanding these largely encouraging epidemiologic data—including evidence of lower all-cause mortality in users than in nonusers of HRT—it is argued here that randomized control trials are needed to provide the necessary basis for wide-spread preventive use of HRT. Critical assessment of observational studies is hampered by our deficient knowledge of the differences in risk at baseline between women with and without climacteric symptoms, and by the fact that healthy women, e.g. without cardiovascular disease, are more likely to be prescribed HRT. Systematic errors therefore might both conceal and exaggerate risks and benefits. Several contexts in which randomized control trials might be informative, ethical, and feasible are suggested.

A descriptive study of occupation and bladder cancer in England and Wales.

Abstract: Bladder cancer is the seventh most common cancer death amongst men in England and Wales. In 1980, there were 2,961 male deaths from bladder cancer, representing 4.3% of all cancer deaths. The two leading known causes of bladder cancer in developed countries are cigarette smoking and occupational exposure to certain aromatic amines. To help confirm previous observations and to provide further etiological clues to occupational causes of bladder cancer in England and Wales, an ecological study was undertaken to generate hypotheses. The percentage of workers in each occupation for areas with high bladder cancer mortality were compared to the average for England and Wales. The numbers of deaths from bladder and lung cancer among males and females aged 25-64 and population data for 400 districts in England and Wales for the periods 1969-73 and 1974-80 were obtained from the Office of Population Censuses and Surveys (OPCS). Because of the 1974 reorganisation of local government boundaries, the method of Cook-Mozaffari (1989) was used to combine data from before and after the boundary changes into a single 1969-80 data set. Bladder and lung cancer standardised mortality ratios (SMRs) for males and females were calculated for each district based on the age-specific mortality rates for England and Wales. High risk areas were identified using the following criteria: the bladder cancer SMR was significantly elevated and at least 10% higher than the lung cancer SMR. This provided ten areas of high risk for males and twelve areas for females, in which the bladder cancer risk was more likely to be due to occupational or other factors than to cigarette smoking. While this study and the Registrar General's decennial analyses of occupation mortality (OPCS, 1978; OPCS, 1986) have no direct data about possible confounding from cigarette smoking, the method used here has minimise this problem by concentrating on areas in which the bladder cancer risk is more likely to be due to occupational or other factors than to cigarette smoking. The sex-specific occupational makeup of each district was determined from 1971 census information provided by the OPCS Longitudinal Study Group. While it would have been preferable to allow for latency by using occupational data from an earlier period, only 1971 census data were routinely available at the district level. The percentage of workers in 220 separate occupations in the high risk areas was compared to the corresponding percentages for England and Wales. Ninety-five per cent confidence interval calulations were based on the upper and lower Poisson expectations of the observed number of workers in each occupation in the high risk areas. As shown in Table I, the high risk areas for males had a significantly higher percentage of workers in 23 occupations

Screening for cervical cancer: is there a place for incorporating tests for the human papillomavirus?

Abstract: Well organized screening programmes for cervical cancer, based on exfoliative cervical cytology, are known to be effective at reducing the incidence of invasive cervical cancer and mortality from the disease. HPV testing should not replace cervical cytology as the first-line approach in screening for cervical cancer, as HPV testing is not sufficiently reliable and some cancers are not associated with HPV infection. Even though there are many unanswered questions about the validity of HPV tests, it is timely to consider whether HPV testing might improve the management of the substantial number of women whose smears are neither clearly normal nor abnormal, but are described as atypical, suspicious or mildly dyskaryotic. The efficacy and costs of incorporating HPV testing into a cervical cancer screening programme need to be evaluated in controlled trials.

The difficulties and costs of ethical assessment of a national research project.

Abstract: In 1990 we applied to the 14 area health board ethical committees for approval of a national study of childhood cancer. All the committees approved the study, but the process was time consuming and costly. The times taken for the committees to grant approval, ranged from two to 36 weeks. The committees had differing requirements. We recommend that a single ethical committee should take responsibility for dealing with each multicentre study in New Zealand. This would ensure uniformity of approach, and minimise delays and costs.