Prenatal and perinatal risk factors for testicular cancer

In an attempt to determine the risk factors responsible for the dramatic increases in testicular cancer incidence in young adults, mothers of testicular cancer cases and controls were questioned about in utero exposures, pregnancy-related conditions, and perinatal factors during their pregnancies with the 202 cases and the 206 controls. The strongest risk factor was low birth weight with a greater than 12-fold risk (confidence interval = 2.8 to 78.1) for subjects weighing 5 lb or less at birth compared to those who weighed over 5 lb. A statistically significant 2-fold increase in risk was associated with unusual bleeding or spotting during pregnancy, regardless of whether medication was taken for this condition. Other exposures during pregnancy associated with a statistically significant increase in risk were: use of "sedatives"; alcohol consumption; and exposure to X-rays. No excess risk was associated with the use of hormones during pregnancy. The findings for birth weight and abnormal uterine bleeding suggest that significant compromise of the normal maternal-fetal environment may be associated with subsequent increase in risk of testicular cancer. However, this increase in risk is not great enough to explain the dramatic increases in testicular cancer that have occurred in young adults.     

Subsite-specific risk factors for colorectal cancer: a hospital-based case-control study in Japan

To investigate the subsite-specific risk factors for colorectal cancer, we conducted a case-control study, using a common questionnaire which inquired about general lifestyles over the past five years (1988–92), at the Aichi Cancer Center Hospital, Nagoya, Japan. This study compared 432 patients with histopathologically diagnosed colorectal cancer (94 proximal colon [cecum, ascending colon, transverse colon]; 137 distal colon [descending colon, sigmoid colon]; 201 rectum [rectosigmoid, rectum]); and 31,782 first-visit outpatient controls who were free from cancer. In both genders, habitual smoking selectively increased the risk for rectum cancer. Soft or loose feces increased the risk for all subsites of colorectal cancer, particularly in female cancer (odds ratio [OR]=4.5). Among female dietary habits, Japanese-style foods decreased the risk factors for distal colon cancer, but increased the risk for proximal colon cancer. These results suggested that the risk factors for colorectal cancer differ by subsite among such a low-risk population as the Japanese. It is suggested also that irritable bowel (soft or loose feces) might be associated with distal subsites of colorectal cancer, independently or combined with habitual smoking. Cancer Causes and Control 1995, 6, 14–22.Drs Inoue and Tajima, Ms Hirose, and Drs Hamajima and Takezaki are with the Division of Epidemiology, Aichi Cancer Center Research Institute, Nagoya, Japan. Authors are also affiliated with the Department of Gastroenterological Surgery, Aichi Cancer Center Hospital, Nagoya, Japan (Drs Hirai and Kato), and the Department of Preventive Medicine, Nagoya University School of Medicine, Nagoya, Japan (Drs Inoue and Ohno). Address correspondence to Dr Inoue, Division of Epidemiology, Aichi Cancer Center Research Institute, 1-1 Kanokoden, Chikusa-ku, Nagoya, Japan, 464. This study was funded in part by a Grant-in-Aid for Cancer Research (4-2) and the Comprehensive 10-year Strategy for Cancer Control from the Ministry of Health and Welfare, Japan.     

Risk factors for breast cancer in Turkish women: a hospital-based case-control study

The aim of this study was to investigate the association between risk factors and breast cancer in Turkish women. In a hospital-based case-control study in Istanbul, 405 patients with histologically confirmed breast cancer were compared with 1050 controls, who were admitted to different departments of the same hospital. Unadjusted odds ratios (ORs) and 95% confidence intervals (CIs) for each risk factor were obtained from logistic regression analyses. Risk factors for breast cancer were found to be early menarche age (OR 3.87, 95% CI 2.46-6.08), use of alcohol (OR 3.87, 95% CI 1.79-8.37), history of diabetes (OR 3.31, 95% CI 2.36-4.64) or hypertension (OR 3.44, 95% CI 2.07-5.71), oral contraceptive use (OR 1.98, 95% CI 1.38-2.85) and hormone replacement therapy (HRT) use (OR 1.94, 95% CI 1.15-3.29). The findings of the present study indicated that history of diabetes or hypertension, use of alcohol, oral contraceptive and HRT, never having breastfed and delayed age at first birth associated with changing of lifestyle led to an increased risk of breast cancer in Turkish women.     

Risk factors for testicular cancer: a case-control study in twins.

Early life and anthropometric risk factors for testicular cancer were examined in a case-control study in England and Wales in which affected male twins were compared with their unaffected male co-twins. Questionnaire data was obtained for 60 twin pairs. Significantly raised risk of testicular cancer occurred in twins who had longer arms and legs than their co-twin. There was a significant excess of testicular cancer reported in non-twin brothers, as well as in twin brothers, of cases. Risk was also significantly raised in relation to cryptorchidism. The results on limb length suggest that factors, perhaps nutritional, affecting growth before puberty, may be causes of testicular cancer. The results on risk in brothers add to evidence of a large genetic component in aetiology of the tumour. The risk associated with cryptorchidism in the twins accords with the hypothesis that cryptorchidism is causally associated with testicular cancer because it is a cause of the malignancy, rather than because the same maternal factors experienced in utero cause both conditions.     

Non-occupational risk factors for bladder cancer: a case-control study

AIMS: The aim of this study was to determine non-occupational risk factors for bladder cancer in Serbia. METHODS AND DESIGN: A hospital-based, case-control study included 130 newly diagnosed bladder cancer patients and the same number of individually matched controls with respect to sex, age (+/- 2 years) and type of residence (rural or urban), from the Clinical Center of Serbia in Belgrade and from the Clinical Center in Kragujevac in central Serbia. The study took place from June 1997 to March 1999. RESULTS: According to multivariate logistic regression analysis, there was an association between: frequency of daily urination (OR = 0.18; 95% CI = 0.08-0.39); consumption of liver (OR = 13.81; 95% CI = 2.49-76.69), canned meat (OR = 8.38; 95% CI = 1.74-40.36), fruit juices (OR = 0.08; 95% CI = 0.01-0.56); the highest tertile of pork (OR = 4.55; 95% CI = 1.30-15.93), cabbage (OR = 0.25; 95% CI = 0.06-1.01) and vinegar (OR = 4.41; 95% CI = 1.18-16.50) intake and risk for bladder cancer. CONCLUSIONS: Consumption of liver, canned meat, pork (h vs l tertile) and vinegar (m vs l tertile) was indicated as a risk factor for bladder cancer, whereas frequent daily urination, consumption of fruit juices and cabbage (h vs l tertile) were indicated as protective factors.     

Prenatal and perinatal risk factors for neuroblastoma

Neuroblastoma is a rare embryonal tumor of childhood for which risk factors are not well known. Using a nested case-control design, we investigated prenatal, perinatal and neonatal risk factors in detail by linking 245 pediatric neuroblastoma cases identified in the Swedish Cancer Register diagnosed in the year 1973-1995 with the Swedish Medical Birth Register. Five living controls per case were randomly selected from the birth registry, matched by gender and age. Increased risks were associated with maternal anemia during pregnancy (odds ratio (OR) = 2.95, 95% confidence interval (CI): 1.53, 5.69), neonatal respiratory distress (OR = 3.61, 95% CI: 1.41, 9.24) and low (below or equal to 7) 1-min Apgar score (OR = 2.23, 95% CI: 1.41, 3.52). Increased risks were limited to cases diagnosed before 1 year of age. Markers of prenatal, perinatal and neonatal distress may be associated with neuroblastoma in infancy, but not with diagnoses at 1 year or above.     

A hospital-based case-control study of breast-cancer risk factors by estrogen and progesterone receptor status

It has been proposed that breast cancers may differ in their pathogenesis and etiology according to their estrogen receptor (ER) and progesterone receptor (PR) status. This hospital-based case-control study in Japan assessed the relationship between known and suspected breast-cancer risk factors and ER and PR status. Information on risk factors was collected from histologically confirmed breast-cancer cases (n=519) and from cancer-free controls (n=9,506). Of 160 cases with known ER status, 58 percent were ER-positive; 38 percent of 157 cases with known PR status were PR-positive. No statistically significant differences were found between ER-positive cf ER-negative cases. However, statistically significant differences between PR-positive cf PR-negative cases were observed for number of full-term pregnancies (P=0.01), menstrual regularity as a teenager (P=0.024), and occupation as housewife (P=0.036). Borderline differences were observed for age at menopause (P=0.074), and age at menarche (P=0.083). This study provides some evidence that etiologic distinctions may be greater between PR-positive and PR-negative breast cancers than between ER-positive and ER-negative breast cancers.Dr Yoo is with the Seoul National University College of Medicine, Korea. Drs Tajima, Miura, Yoshida, Murai, and Kuroishi are with the Aichi Cancer Center, Nagoya, Japan. Dr Lee is with the College of Natural Science, Hallym University, Chuncheon, Korea. Drs Risch and Dubrow are with Yale University School of Medicine, New Haven, CT, USA. Address correspondence to Dr Yoo, Department of Preventive Medicine, Seoul National University College of Medicine, 28 Yongon-dong, Chongo-gu, Seoul 110-460, Korea. Keun-Young Yoo was a recipient of a grant from the Exchange Scientist Program of the US National Institutes of Health (G-5-0111). Robert Dubrow received support from a US National Cancer Institute Preventive Oncology Academic Award (K07-CA01463).     

Rectal cancer and occupational risk factors: a hypothesis-generating, exposure-based case-control study

In 1979, a hypothesis-generating, population-based case-control study was undertaken in Montreal, Canada, to explore the association between occupational exposure to 294 substances, 130 occupations and industries, and various cancers. Interviews were carried out with 3, 630 histologically confirmed cancer cases, of whom 257 had rectal cancer, and with 533 population controls, to obtain detailed job history and data on potential confounders. The job history of each subject was evaluated by a team of chemists and hygienists and translated into occupational exposures. Logistic regression analyses adjusted for age, education, cigarette smoking, beer consumption, body mass index, and respondent status were performed using population controls and cancer controls, e.g., 1,295 subjects with cancers at sites other than the rectum, lung, colon, rectosigmoid junction, small intestine, and peritoneum. We present here the results based on cancer controls. The following substances showed some association with rectal cancer: rubber dust, rubber pyrolysis products, cotton dust, wool fibers, rayon fibers, a group of solvents (carbon tetrachloride, methylene chloride, trichloroethylene, acetone, aliphatic ketones, aliphatic esters, toluene, styrene), polychloroprene, glass fibers, formaldehyde, extenders, and ionizing radiation. The independent effect of many of these substances could not be disentangled as many were highly correlated with each other.     

Lung cancer risk in never-smokers: a population-based case-control study of epidemiologic risk factors

Background  

We conducted a case-control study in the greater Toronto area to evaluate potential lung cancer risk factors including environmental tobacco smoke (ETS) exposure, family history of cancer, indoor air pollution, workplace exposures and history of previous respiratory diseases with special consideration given to never smokers.     

Gastric cancer risk factors: a case-control study based on medical records

Four hundred and sixty gastric cancer patients who had undergone operation at the National Cancer Center Hospital and an equal number of age-matched controls were analyzed in order to estimate the influence of gastric cancer family inheritance and cigarette smoking habit. Relative risks for cigarette smoking habit, for gastric cancer family inheritance and for both were 2.88, 1.67 and 4.12, respectively. Earlier age of onset of gastric cancer was observed in the gastric cancer cases with both risk factors as compared with the other patients.     

Breast cancer risk factors in Italian women: a multicentric case-control study

To evaluate the importance of several risk factors for breast cancer in the Italian female population, a large multicentric case-control study was conducted in 10 breast clinics in Italy. The study included 1,556 women affected by breast cancer, histologically and/or cytologically confirmed. Controls were 1,505 women admitted to a hospital in the same town, matched with cases for residence and with the same age distribution of the Italian female population. The risk factors considered in this study were family history of breast cancer, reproductive history, height and weight, use of oral contraceptives, other hormonal therapies and smoking history. The results of this study confirm the significant role of a positive family history of breast cancer (RR = 2.37); the relative risk was even higher when a first-degree relative was affected or the breast cancer was bilateral. The analysis of the reproductive history showed a significant trend of increasing risk with increasing age at first birth and, although less evident, with increasing number of children. Quetelet's index (kg/m-2) was positively correlated with breast cancer risk, mostly in postmenopausal women. Among other studied factors, only late age at menopause confirmed an increased risk for breast cancer, whereas age at menarche, use of oral contraceptives and smoking histories did not show any significant correlation with breast cancer risk. These results are in substantial agreement with other international studies, but represent an interesting contribution to studies about the Italian female population.     

Never smokers and lung cancer risk: a case-control study of epidemiological factors

We performed an analysis of potential epidemiological risk factors for lung cancer using data from 280 cases and 242 hospital-based controls, all lifetime never smokers (those who had smoked <100 cigarettes in their lifetimes) and frequency matched on age, gender and ethnicity. The data on demographic characteristics, medical history of respiratory diseases (asthma, emphysema, pneumonia and hay fever), weight and height, family history, female characteristics and environmental tobacco smoke (ETS) and dust exposure were derived from personal interviews. We performed a logistic regression analysis of these variables adjusting for age, gender, ethnicity, income and years of education. Exposure to ETS (OR = 2.08, 95% CI [1.25-3.43]) and dusts (OR = 2.43, 95% CI [1.53-3.88]) were associated with significantly increased risk. In the analysis for joint effects, exposure to both ETS and dusts conferred a higher risk (OR = 3.25, 95% CI [1.58-6.70]) than exposure to either alone. Family history of any cancer with onset before age 50 in at least 1 first degree relative was a significant risk predictor (OR = 1.70, 95% CI [1.10-2.64]). Individuals with a self-reported physician-diagnosed history of hay fever, but not asthma, had a decreased lung cancer risk (OR = 0.57, 95% CI [0.35-0.92]). In the multivariate analysis, exposure to ETS and dusts, and family history of cancer with onset before age 50 were significant risk factors, while a history of hay fever (occurring without asthma) was significantly protective.     

Physical activity, water intake and risk of colorectal cancer in Taiwan: a hospital-based case-control study.

The age-adjusted mortality rates of colorectal cancer have been rising in Taiwan over the past 2 decades, and colorectal cancer is now the third leading cause of cancer mortality in the country. We conducted a hospital-based case-control study to clarify the nature of the association between physical activity, water intake and colorectal-cancer risk in Taiwan. A total of 163 subjects (aged 33-80 years) with histologically confirmed primary colorectal cancer and 163 hospital controls were enrolled during 1992. Dietary intake, physical activity and other lifestyle activities were assessed using a comprehensive food-frequency and lifestyle-activity questionnaire. Adjusted odds ratios (OR) and 95% confidence intervals (CI) were estimated using conditional logistic-regression analysis. A strong inverse dose-response relation between increased water intake and rectal cancer was found among men after adjustment for other risk factors (p for trend = 0.0005). The OR for rectal cancer among men in the highest tertile of water intake was 0.08 (95% CI, 0.02-0.35) compared with that among men in the lowest tertile (OR = 1). Similar but not significant trends were seen among women (p = 0.29). The OR for colon cancer among men with active leisure-time physical activity was 0.19 (95% CI, 0.05-0.77) times that among sedentary men (p for trend = 0.03). However, physical activity was not associated with colon-cancer risk among women (p = 0.48). No differences in the amount of water intake were found related to level of physical activity. These findings add to the evidence that leisure-time activity may reduce colon-cancer risk, not only in high-risk but also in low-risk populations, and support the potential beneficial effect of increased water intake in reducing colorectal-cancer risk.     

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

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 110 cases from among successive birth cohorts from 1973 through 1984, identified by the Swedish Medical Birth Registry, the latter based on medical records. From the Birth Registry, we matched 5 controls without cancer to each case by sex and date of birth. Wilms'-tumor children were more likely to have mothers who had been exposed to penthrane (methoxyflurane) anesthesia during delivery than mothers of controls (odds ratio (OR) = 2.4; 95% confidence interval (CI) 1.1 to 5.1); this excess risk was higher in females than males and increased with age at diagnosis. Wilms'-tumor cases were also more likely to have had physiologic jaundice (OR = 2.3; 95% CI 1.1 to 5.0). Higher parity of the mother decreased the risk of Wilms' tumor among females (OR = 0.7; 95% CI 0.5 to 1.0). We were unable to confirm the reported increased risks of Wilms' tumor for those with high birth weights or with a maternal history of hypertension or fluid retention during pregnancy, nor did we find any association with mother's age at delivery, previous stillbirth, previous live birth, gestational length or height of the child.     

Urinary bladder cancer risk factors in men: a Spanish case-control study.

The rising incidence of urinary bladder cancer is alarming and potential relationships with different risk factors have been postulated. The purpose of this study was to examine the possible relationship between different environmental risk factors and urinary bladder cancer. All men with urinary bladder cancer who were admitted to the Department of Urology of Reina Sofia University Hospital of Cordoba, Spain over 1 year were included in our study. Men were administered an interview questionnaire, which included data on history of known urinary bladder cancer risk factors. Comparisons between men with urinary bladder cancer (cases) and those with nonmalignant urological disease (controls) were made. The study included 74 cases and 89 controls. The variables associated with malignant lesions on univariate analysis were age, smoking and drinking alcohol. Meanwhile, fish, poultry and beef consumption were proved to be protective factors. The risk factors identified by the logistic regression analysis were age, smoking and fluid intake. The independent protective factors on the multivariate analysis were fish and poultry consumptions. Smoking was found to be the principal independent risk factors for urinary bladder cancer. Our results call for further investigation of urinary bladder cancer risk factors; future studies should preferably be performed on large prospective cohorts, to increase their validity.     

Nutritional factors in colorectal cancer risk: a case-control study in Majorca.

The relationship between energy intake, selected nutrients and colorectal cancer was investigated in the population of Majorca, a Spanish island in the Mediterranean basin. A population-based case-control study using food frequency questionnaires was conducted during the period 1984-1988 and included 286 cases of colorectal cancer, 295 population controls and 203 hospital controls. Food composition tables and ad-hoc estimates of portion sizes were used to derive intake estimates of 29 nutrients and of total calories. Relative risks were calculated for quartiles of consumption of each specific nutrient after adjustment for total calorie intake. Colorectal cancer was found associated with dietary intake of total calories (RRs = 1.0, 1.6, 1.6, 2.6) and cholesterol (RRs = 1.0, 0.9, 1.7, 1.7) and a protective effect was associated with the intake of fibre from legumes (pulses) and folic acid. The associations and the trends were statistically significant. Among the main energy-supplying nutrients, after adjustment for calories from other sources, increased risks were found for protein (RRs = 1.0, 1.1, 1.7, 2.5), notably animal protein, and carbohydrates (RRs = 1.0, 1.5, 1.4, 2.2), whereas no effects were found for increased consumption of lipids or saturated fats.     

The risk factors of prostate cancer: a multicentric case-control study in Iran.

Prostate cancer (PC), in Iran, is the third most frequently diagnosed visceral cancer among men and the seventh most common underlying cause of cancer mortality. We evaluated the relation between speculated factors and PC risk using data from a multicentric case-control study conducted in Iran from 2005 to 2007 on 130 cases of incident, clinicopathologically confirmed PC, and 75 controls admitted to the same network of hospitals without any malignant disease. Odds ratios (OR) and corresponding 95% confidence intervals (CIs) were estimated using conditional logistic regression models. The risk of PC was increased with aging (OR: 5.35, 95% CI: 2.17-13.19; P<0.0001), and with the number of sexual intercourse >or=2 times/week (OR: 3.14, 95% CI: 1.2-8.2; P=0.02). One unit elevation in serum estradiol and testosterone concentration was related to increase (OR: 1.04, 95% CI: 1.01-1.06; P=0.006) and decrease (OR: 0.79; 95% CI: 0.64-0.96; P=0.02) of PC risk, respectively. Cases were less likely to have a history of diabetes (OR: 0.34, 95% CI: 0.12-0.98; P=0.04). Increasing in dietary consumption of lycopene and fat was associated with declined (OR: 0.45, 95% CI: 0.09-2.12) and increased (OR: 2.38, 95% CI: 0.29-19.4) PC development, respectively. Other factors including educational level, marriage status, dietary meat consumption, vasectomy and smoking have not been shown to affect PC risk in the Iranian population. Our study adds further information on the potential risk factors of PC and is the first epidemiologic report from Iran. However, justification of these results requires more well-designed studies with a larger number of participants.     

Dietary factors and risk of pancreatic cancer: results of a Canadian population-based case-control study

Dietary information from a case-control study of pancreatic cancer conducted in Metropolitan Toronto between 1983 and 1986 is reported. A total of 249 cases and 505 population-based controls completed quantitative diet histories from which total caloric intake and the intake of a number of nutrients were estimated. A positive association with total caloric intake was observed with a relative risk of 2.39, 95% confidence interval 1.18-4.83 (highest versus lowest quartile), due primarily to the intake of carbohydrates. Inverse associations were seen with fibre from fruit, vegetable and cereal sources, with a relative of risk of 0.42, 0.22-0.78 (highest versus lowest quartile), for total fibre intake.