A polymorphism in the CYP17 gene increases the risk of breast cancer.

We conducted a case-control study to determine whether a polymorphism in the CYP17 gene was associated with risk of breast cancer. We found an increased risk of advanced breast cancer in women carrying an A2 allele. The odds ratio was 2.

A prevalent missense substitution that modulates activity of prostatic steroid 5alpha-reductase.

Prostate cancer is the most common serious cancer diagnosed in men in the United States. This disease is also characterized by a striking racial/ethnic variation in incidence: highest in African-Americans, intermediate in Caucasians, slightly lower in Latinos, and lowest in Asians. Ample biochemical and epidemiological evidence suggests a role for androgens, particularly testosterone and dihydrotestosterone, in prostate cancer etiology.

Strength of linkage disequilibrium between two vitamin D receptor markers in five ethnic groups: implications for association studies.

Markers in the 3' end of the vitamin D receptor gene have recently been associated with prostate cancer risk. To evaluate the adequacy of the commonly used BsmI restriction fragment length polymorphism as a marker of this locus, we genotyped 627 individuals from five ethnic groups for this marker, as well as for a polymorphic site in the 3' untranslated region of this gene. At the latter site, we identified 12 alleles, A13 to A24, of a poly(A) microsatellite.

Family history and risk of colorectal cancer in the multiethnic population of Hawaii.

Increased risk of colorectal cancer in individuals with family history of the disease has been observed consistently in past studies. However, limited attention has been given to the influence of ethnicity, the characteristics of the proband's tumor, and kinship. A population-based case-control study was conducted between 1987 and 1991 in Hawaii among 1,192 incident colorectal cancer cases and 1,192 sex-, age-, and ethnicity-matched population controls.

Tofu and risk of breast cancer in Asian-Americans.

Breast cancer rates among Asian-Americans are lower than those of US whites but considerably higher than rates prevailing in Asia. It is suspected that migration to the US brings about a change in endocrine function among Asian women, although reasons for this change remain obscure. The high intake of soy in Asia and its reduced intake among Asian-Americans has been suggested to partly explain the increase of breast cancer rates in Asian-Americans.

Relative weight, weight change, height, and breast cancer risk in Asian-American women.

Background: Breast cancer incidence rates have historically been four to seven times higher in the United States than in China or Japan, although the reasons remain elusive. When Chinese, Japanese, or Filipino women migrate to the United States, their breast cancer risk rises over several generations and reaches that for white women in the United States, indicating that modifiable exposures are involved. In a previous report on this case-control study of breast cancer in Asian-American women, designed to take advantage of their diversity in risk and lifestyle, we demonstrated a sixfold gradient in risk by migration history, comparable to the international differences in breast cancer incidence rates.

Risk factors for lower urinary tract cancer: the role of total fluid consumption, nitrites and nitrosamines, and selected foods.

Many cases of lower urinary tract cancer cannot be attributed to the known risk factors of cigarette smoking and certain occupational chemical exposures. Data from a case-control study conducted on Oahu, Hawaii, from 1979 to 1986 were used to determine the role of several additional exposures in the etiology of lower urinary tract cancer, such as total fluid intake and dietary nitrites and nitrosamines, as well as intake of selected foods. A total of 195 male and 66 female lower urinary tract cancer cases of Caucasian and Japanese ancestry were matched to two population-based controls on age, sex, and race.

Menstrual and reproductive factors and risk of breast cancer in Asian-Americans.

We conducted a population-based case-control study of breast cancer among Chinese-, Japanese- and Filipino-American women in Los Angeles County Metropolitan Statistical Area (MSA), San Francisco-Oakland MSA and Oahu, Hawaii. One objective of the study was to quantify breast cancer risks in relation to menstrual and reproductive histories in migrant and US-born Asian-Americans and to establish whether the gradient of risk in Asian-Americans can be explained by these factors. Using a common study design and questionnaire in the three study areas, we successfully conducted in-person interviews with 597 Asian-American women diagnosed with incident, primary breast cancer during the period 1983-87 (70% of those eligible) and 966 population-based controls (75% of those eligible).

Nutrition and prostate cancer.

Epidemiologic evidence on the relation between nutrition and prostate cancer is reviewed. Little is known about the etiology of prostate cancer, despite its prominence as the leading cancer among men in the United States. Rational mechanisms for dietary influences on prostate carcinogenesis, including effects on production or metabolism of androgenic hormones, have been proposed, but because few suitable animal models have been developed, the laboratory literature on diet and prostate cancer is sparse.

Serum androgens and sex hormone-binding globulins in relation to lifestyle factors in older African-American, white, and Asian men in the United States and Canada.

Differences in endogenous androgen levels have been hypothesized to explain ethnic differences in prostate cancer risk. To examine this hypothesis, we gathered data on serum concentrations of androgens and sex hormone-binding globulin (SHBG) in healthy older men from four ethnic groups at different levels of prostate cancer risk. As part of a population-based case-control study of prostate cancer we conducted in California, Hawaii, and Vancouver, Canada, 1127 African-American, white, Chinese-American, and Japanese-American control men, mostly ages 60 years or older (mean age, 69.

An ecological study of diet and lung cancer in the South Pacific.

Incidence rates of lung cancer have been markedly lower for Fiji than for other South Pacific countries, despite similar rates of smoking. We conducted population-based surveys in several island nations of the South Pacific (Cook Islands, Fiji, Tahiti and New Caledonia) and used data from Caucasian, Japanese, Hawaiian, Filipino and Chinese controls in a case-control study of lung cancer in Hawaii to investigate the role of diet in explaining differences in lung cancer incidence among 20 ethnic-sex groups. In a stepwise linear regression of lung cancer rates on smoking, diet and other variables, smoking, as expected, explained the majority (61%) of the variability in incidence.

Cost-efficient design of a diet validation study.

Validation studies of food frequency questionnaires (FFQs) describe the extent to which the FFQ reflects true diet and the relation between measured and true diet (calibration). Calibration data can be used to estimate the relation between disease and diet that would have been observed in the absence of error due to the FFQ. In this paper, the authors consider the optimal design of a validation study when the goal is precise calibration of an FFQ.

Evidence of an X-linked or recessive genetic component to prostate cancer risk.

We used data from a population-based cohort study of blacks, Hispanics, Japanese and whites to examine the frequency of prevalent prostate and breast cancer by family history status of first-degree relatives (parents and siblings). Independent of race, the age-adjusted relative risk for prevalent prostate cancer in subjects with affected brothers was approximately two times that in subjects with affected fathers (P < 0.00005).

Prostate cancer in relation to diet, physical activity, and body size in blacks, whites, and Asians in the United States and Canada.

Background: International and interethnic differences in prostate cancer incidence suggest an environmental, potentially modifiable etiology for the disease.

Purpose: We conducted a population-based case-control study of prostate cancer among blacks (very high risk), whites (high risk), and Asian-Americans (low risk) in Los Angeles, San Francisco, Hawaii, Vancouver, and Toronto. Our aim was to evaluate the roles of diet, physical activity patterns, body size, and migration characteristics on risk in these ethnic groups and to assess how much of the interethnic differences in risk might be attributed to interethnic differences in such lifestyle characteristics.

Vasectomy and prostate cancer: results from a multiethnic case-control study.

Background: Vasectomy, a widely used form of contraception, has been associated in some studies with increased prostate cancer risk.

Purpose: We assessed this association on the basis of data collected in a large multiethnic case-control study of prostate cancer that was conducted in the United States (Los Angeles, San Francisco, and Hawaii) and Canada (Toronto and Vancouver).

Methods: In home interviews conducted with newly diagnosed prostate cancer case patients and population control subjects, we obtained information on the participants' medical history, including a history of vasectomy and the age at which the procedure was performed, as well as other potential risk factors.

Family history and prostate cancer risk in black, white, and Asian men in the United States and Canada.

Increased risk of prostate cancer in men with a family history of the disease has been observed consistently in epidemiologic studies. However, most studies have been confined to white men; little is known about familial aggregation of prostate cancer in populations with unusually high incidence, such as African Americans, or in populations with low incidence, such as Asian-Americans. The authors report results from a population-based case-control study of prostate cancer among blacks, whites, and Asian-Americans in the United States and Canada.

Maternal exposure to N-nitrosatable drugs as a risk factor for childhood brain tumours.

Background: Animal models suggest that compounds containing a nitrosyl group (N-nitroso compounds (NNO)) can act as potent transplacental carcinogens. Many common drug formulations have the potential to undergo nitrosation in vivo. The association between maternal use of nitrosatable drugs during pregnancy and development of brain tumours in the offspring was examined in a SEER-based case-control study.

The rise of cancer among the elderly in Hawaii.

The purpose of this study was to determine if time trends in cancer incidence among the elderly in Hawaii were similar to the trends observed in the mainland United States and to determine if the trends were comparable among the various ethnic groups living in Hawaii. Average annual incidence rates per 100,000 persons, age 65 or older, were determined by sex and ethnicity for the time periods 1973 to 1977 and 1983 to 1986 through the Hawaii Tumor Registry, a population-based central cancer registry. The incidence of all cancers combined increased 27% among men and 26% among women between the 2 time periods.

A case-control study of mesothelioma and employment in the Hawaii sugarcane industry.

We conducted a case-control study of 93 mesothelioma cases and 281 cancer controls to determine whether sugarcane workers exposed to biogenic silica fibers were at increased risk of mesothelioma. We found no important excess risk of mesothelioma in sugarcane workers [odds ratio (OR) = 1.3; 95% confidence interval (CI) = 0.

Animal fat consumption and prostate cancer: a prospective study in Hawaii.

Whereas case-control studies have been very consistent in suggesting a positive association between intake of dietary fat, especially animal fat, and prostate cancer, the results from past cohort studies have been mostly inconclusive. In this study, we evaluated consumption of high-fat animal products, raw vegetables, and fresh fruits, as well as obesity, smoking, and drinking, in relation to subsequent occurrence of prostate cancer. We studied a cohort of 20,316 men of various ethnicities interviewed between 1975 and 1980 in Hawaii.

A pilot study on the use of plasma carotenoids and ascorbic acid as markers of compliance to a high fruit and vegetable dietary intervention.

The authors examined the feasibility of using plasma carotenoids and ascorbic acid as markers of compliance for dietary intervention trials aimed at increasing the quantity and variety of the fruit and vegetable intake of free-living individuals. Nineteen former cancer patients who had been successfully treated for a stage I or II squamous cell carcinoma of the mouth, pharynx, larynx, or lung were recruited. Subjects served as their own controls.

Relationship of serum uric acid to cancer occurrence in a prospective male cohort.

Uric acid is a potent antioxidant and thus might protect against cancer. To test this hypothesis, we examined the relationship of serum uric acid to subsequent cancer incidence in a cohort of Japanese men in Hawaii. The study population consisted of 7889 men identified in the years 1965-1968 and followed by active hospital surveillance through November 1991.

The role of family history in risk of childhood brain tumors.

Background: Although brain tumors are the second most frequent malignancy in children, relatively little is known about the role of family history in risk of these tumors.

Methods: Children under the age of 18 years (n = 361) in whom primary brain tumors were diagnosed were identified from eight United States population-based Surveillance, Epidemiology, and End Results registries and compared to matched controls (n = 1083) identified by random-digit dialing. Information regarding family history of birth defects or tumors was obtained, along with data on other potential risk factors, from interviews with the mothers and fathers of the index children.