The relationship of hepatitis history and pathological diagnosis of primary liver cancer.

During the analysis of risk factors in relation to primary liver cancer, we noticed an association between the confirmed (as opposed to probable) pathologic diagnosis of liver cancer and a positive history of hepatitis. This report pursues the observation using data from the Selected Cancers Study. Study subjects included 168 men who lived in areas covered by eight cancer registries in the U.S., and were pathologically diagnosed with confirmed or probable primary liver cancer during 1984-1988. The results showed that men with confirmed primary liver cancer were six times more likely to have a hepatitis diagnosed within 3 years before liver cancer detection, compared with those with probable primary liver cancer. Further analyses showed that men with a confirmed primary liver cancer or with a recent hepatitis more likely had a tissue specimen obtained from a surgery, and less likely had one from an aspiration. Upon adjustment for type of specimen, the association between pathological confirmation of primary liver cancer and recent hepatitis persisted. The results raised questions whether recent hepatitis and its pathologic changes influence choice of tissue-collecting procedure and ultimate pathological diagnosis of primary liver cancer. Other factors that might be related to the findings also need to be examined in future studies.

Risk factors for non-Hodgkin's lymphoma according to family history of haematolymphoproliferative malignancies.

BACKGROUND: Aetiological profiles of non-Hodgkin's lymphoma (NHL) may differ depending upon whether the disease is inheritance-related or sporadic. Because familial risk (a probable surrogate of inheritance-relatedness) of NHL is influenced by haematolymphoproliferative malignancies (HLPM), we evaluated whether non-familial risk factors differ between NHL with and without a family history of HLPM, using the Selected Cancers Study data. METHODS: Cases were 1511 men aged 31-59 and diagnosed with NHL during 1984-1988. Controls were men without NHL, frequency-matched to cases by age range and cancer registry (n = 1910). These groups were compared: cases with a family history of HLPM and without, and controls without such a family history. RESULTS: Polytomous logistic regression analyses showed that the odds ratio (OR) estimates of homosexual behaviour were 18.2 (95% confidence interval (CI) : 4.8-69.4) and 5.6 (95% CI : 3.3-9.5) for NHL with and without a family history of HLPM, respectively. The corresponding estimates were 3.9 (95% CI : 1.7-8.9) and 2.2 (95% CI : 1.5-3.1) for history of enlarged lymph nodes. Variables only related to NHL with a family history were use of heroin (OR = 15.6, 95% CI : 3.4-70.4), exposure to a chlorinated hydrocarbon pesticide (OR = 2.3, 95% CI : 1.0-5.0), occupational exposure to plywood, fibreboard or particleboard (OR = 2.0, 95% CI : 1.2-3.4) and history of liver diseases (other than hepatitis or cirrhosis) (OR = 6.5, 95% CI : 1.2-36.2). The association between homosexual behaviour and NHL among men with a family history was stronger for those aged 31-44, especially for B-cell type of the disease. CONCLUSIONS: This study suggests differences in the risk factor profiles between NHL with and without a family history of HLPM. The higher risks of NHL for homosexual behaviour and heroin use, surrogates of HIV infection, in men with a family history of HLPM imply that genetic susceptibility may be influential on the occurrence of HIV-related NHL.

Occupational chlorophenol exposure and non-Hodgkin's lymphoma.

Occupational exposure to chlorophenols is suspected to increase non-Hodgkin's lymphoma (NHL) risk. This association was examined using data on 995 NHL cases and 1783 controls from the Selected Cancers Study, a population-based case-control study of men aged 32 to 60 years from eight population-based cancer registries conducted from 1984 to 1988. Potential chlorophenol exposure was characterized by an industrial hygienist using intensity estimates and confidence ratings, based upon review of verbatim job histories. Cases with substantial chlorophenol exposure had a significantly greater number of years of chlorophenol exposure (median years: cases, 4.0; controls, 2.0; P = 0.046); however, in conditional logistic regression models, the odds ratio for more than 8 years of substantial exposure was 1.51 (95% CI, 0.88 to 2.59). Overall, the findings do not provide strong support for an association with NHL risk. Chlorophenol exposure in this study is not based upon measured values and, therefore, may fail to characterize actual chlorophenol exposures accurately. Because of the large presence of machinists in the potentially chlorophenol-exposed group, these results may be underestimated by exposure misclassification if these subjects were not exposed to chlorophenolic biocides. However, these results are consistent with other findings, which suggest that chlorophenol exposure is not likely to be a strong risk factor for NHL.

A multivariate analysis of interstate variation in fertility of teenage girls.

A multiple regression model was used to determine the correlates of state-to-state variation in fertility of teenage girls. The independent variables were the abortion-t0-live birth ratio, contraception/conception ratio, racial composition, adult personal income, per cent urban population, and adult educational attainment. The model explained 69 per cent of the interstate variation in 1974 fertility. Both the racial composition and the abortion ratio were significantly (p less than .01) correlated with fertility. With 1970--1974 change in fertility as the dependent variable, the model explained 80 per cent of the variation, with income as the most strongly correlated variable. The contraception/conception ratio was also significant (p less than .01), as was racial composition (p less than .05). Factor analysis of the independent variables showed that the six variables were well accounted for by three factors representing culture/education status, abortion availability, and contraception availability. The analysis showed that utilization of both contraception and abortion was important in determining the fertility of a state's teenagers. Increased availability of publicly subsidized contraception in low income areas and increased availability of abortion in low income and rural areas might be expected to result in decreased fertility of teenage girls.

Proxy respondents and the validity of occupational and other exposure data. The Selected Cancers Cooperative Study Group.

As part of a multicenter cancer case-control study conducted in 1984-1988, a proxy interview was attempted for all cases who were initially interviewed for the study but who died during the 4-year data collection period. To assess the validity of using wives, other relatives, or other informants to obtain information about a subject, the authors compared occupational and other exposure data obtained from 270 male cancer cases and their proxy respondents. The primary focus of the case-control study was on Vietnam military service and exposure to phenoxy herbicides, but cases and their proxy respondents were also asked about occupational and other exposures relevant to the cancers. The accuracy of reporting for specific occupational exposures (e.g., asbestos and formaldehyde) and specific occupations (e.g., dry cleaning and meat packing or processing) was poor, although the latter improved somewhat when only case-spouse pairs were examined. Similarly, there was poor sensitivity in the reporting of herbicide exposure information in farming and other related occupations. In contrast, the reporting of certain demographic characteristics, childhood history characteristics, and use of alcohol and cigarettes was relatively good, and was even better when only case-spouse pairs were examined. The poor quality of proxy information for detailed exposure information suggests the need for careful use and interpretation of proxy information in epidemiologic studies.

Abortion utilization: does travel distance matter?

The further a woman must travel in order to obtain an abortion, the less likely she is to get one. Distance is especially disadvantageous to blacks, and most so to black teenagers. Distance discourages use among rural as well as urban women. Opening new clinics increases abortion use in nearby communities.

Cigarette smoking and nasopharyngeal cancer: an analysis of the relationship according to age at starting smoking and age at diagnosis.

To examine whether the association between smoking and nasopharyngeal cancer varies according to age at starting smoking and age at diagnosis of the disease, we compared 113 men with nasopharyngeal cancer diagnosed between 31 and 59 years old who lived within eight cancer registry areas to 1,910 controls selected by random-digit telephone dialing. Compared to smoking which began at the age of 22 years or older, the risk estimates were 0.4 (95% confidence interval (CI) 0.2-0.9) and 0.8 (95%CI 0.4-1.5) for smoking begun at the ages of 18-21 and 17 years or younger, when adjusted for pack-years smoked and other potential confounders (p for trend > 0.8). In contrast, the risk estimates adjusted for age at starting smoking and other variables were 1.3 (95%CI 0.7-2.6), 1.9(95%CI 0.9-4.0) and 3.0(95%CI 1.4-6.2) for 15-29.9, 30-44.9 and 45 or over, relative to 15 or less pack-years smoked (p for trend < 0.005). The analyses were repeated for subgroups in terms of age at diagnosis. The relative risks of ever-smoking and the dose-effect relation between pack-years and the risk of the disease were not significantly different between men whose cancer was diagnosed at the age 49 or younger and those whose tumor was diagnosed between the ages 50 and 59. This study suggests that the magnitude of the risk for nasopharyngeal cancer may not vary significantly with the age at which smoking begins, and age at which the disease is diagnosed.

A population-based case-control study of the relationship between cigarette smoking and nasopharyngeal cancer (United States).

This case-control investigation, based on the Selected Cancers Study, assesses the association between cigarette smoking and nasopharyngeal cancer, a relatively rare neoplasm in the United States. Men who were diagnosed pathologically with nasopharyngeal cancer during 1984-88 were included as cases in the analysis if they were 15 to 39 years old in 1968, and lived in the areas covered by eight cancer registries in the US (n = 113). Control men were selected by random-digit telephone dialing (n = 1,910). Using logistic regression analysis with adjustment for potential confounding factors, it was found that relative to nonsmokers, the risks of nasopharyngeal cancer were 2.3 (95 percent confidence interval [CI] = 1.3-4.0) and 1.4 (CI = 0.8-2.6) for former and current smokers, respectively. Using pack-years as a measure, adjusted odds ratio (OR) estimates were 1.3, 1.8, 2.5, and 3.9 for smoking for less than 15, 15-29, 30-44, and 45 or more pack-years, respectively. When squamous cell carcinoma was used as an outcome, the smoking/nasopharyngeal-cancer association became stronger. The analysis did not show interactions between smoking and alcohol consumption, or prior nasal diseases. The results of this study suggest that cigarette smoking may be related to the occurrence of nasopharyngeal cancer (especially squamous cell carcinoma) among US men.

Relation of cigarette smoking to non-Hodgkin's lymphoma among middle-aged men.

Because of previous inconsistencies in the observed relation of cigarette smoking to non-Hodgkin's lymphoma, this association was investigated in the Selected Cancers Study, a population-based case-control study of 1,193 non-Hodgkin's lymphoma cases and 1,903 controls, conducted between 1984 and 1988. Study subjects were men, and the median age of non-Hodgkin's lymphoma cases was 50 years (range, 32-60 years). As compared with the risk among men who had never smoked cigarettes, the risk among ever smokers was not increased (odds ratio (OR) = 1.05, p approximately 0.50), but the risk was significantly elevated among men who reported smoking > or = 2 1/2 packs per day and among men who had smoked for 30-39 years (OR = 1.45 in each group, p < 0.05). The estimated odds ratio among the 350 heavy smokers (> or = 50 pack-years) was 1.41 (95% confidence interval 1.08-1.85) after controlling for educational achievement, various occupational and medical exposures, and other potential confounders. The observed associations, however, tended to vary by age, with the odds ratio among heavy smokers decreasing from 2.8 among 32- to 44-year-olds to 1.1 among men over 55 years of age. These age-related differences, which may account for some of the inconsistencies seen in previous studies of cigarette smoking and non-Hodgkin's lymphoma, should be considered in future investigations.

Occupational exposure to chlorophenol and the risk of nasal and nasopharyngeal cancers among U.S. men aged 30 to 60.

BACKGROUND: Elevated rates of nasal and nasopharyngeal cancers have been associated with wood-related occupational exposures, including chlorophenols, formaldehyde, and wood dust. METHODS: Occupational information was obtained from 43 nasal carcinoma cases, 92 nasopharyngeal carcinoma cases, and 1909 controls, by interview. Exact conditional logistic regression was used to evaluate the association of these cancers with chlorophenol exposure, estimated from a review of verbatim responses. RESULTS: Both nasal and nasopharyngeal cancers were significantly associated with estimated duration of chlorophenol exposure. For nasopharyngeal cancer, elevated risk was observed among those who held jobs assigned medium or high intensity chlorophenol exposure (n(exposed)=18, OR=1.94, 95% CI=1.03-3.50) and among those with 10+ years in jobs assigned high intensity with high certainty (n(exposed)=3, OR=9.07, 95% CI=1.41-42. 9). Controlling for estimated formaldehyde and wood dust exposure did not alter these findings, as much of the estimated chlorophenol exposure was among machinists. CONCLUSIONS: These findings support the hypothesis that occupational exposure to chlorophenol is a risk factor for nasal and nasopharyngeal cancer, although the role of machining-related exposures warrants further assessment.

Non-Hodgkin's lymphoma and family history of malignant tumors in a case-control study (United States).

Using data from a case-control study in the United States (the Selected Cancers Study), we examined the relationship between non-Hodgkin's lymphoma (NHL) and family history of different cancers. Cases were 1,511 men aged 31 to 59 years and diagnosed pathologically with non-Hodgkin's lymphoma during 1984-88. Controls were men, frequency-matched to cases by age range and cancer registry (n = 1,910). All study subjects with acquired immunodeficiency syndrome were excluded from analyses. Our results showed that the risk of NHL is associated with a history of lymphoma (odds ratio [OR] = 3.0, 95 percent confidence interval [CI] = 1.7-5.2) and hematologic cancer (OR = 2.0, CI = 1.2-3.4) in first-degree relatives after adjustment for age, ethnic background, and educational level. Further analyses were performed for the subgroups defined by age at diagnosis (younger than 45 years cf 45 years or older). The association of NHL with a family history of lymphoma and hematologic cancer was found primarily among men aged 45 and older (OR = 4.1, CI = 1.9-8.8 for lymphoma and OR = 2.3, CI = 1.3-4.0 for hematologic cancer). The association among men aged 45 and older did not vary by whether or not there were any familial patients diagnosed at the age of 45 or older. No significant associations could be found for a family history of lung cancer, breast cancer, prostate cancer, colon cancer, skin cancer, liver cancer, stomach cancer, brain cancer, thyroid cancer, or myeloma. This study suggests that the familial risk of NHL is influenced primarily by hematolymphoproliferative malignancies rather than other cancers. The familial effects of hematolymphoproliferative malignancies may be stronger for men aged 45 to 59, compared with those aged 31 to 44.

Occupational risk factors for sarcoma subtypes.

Herbicides, chlorophenols, and other occupational exposures are suspected risk factors for soft-tissue sarcoma, but the epidemiologic evidence is inconsistent. Given that soft-tissue sarcomas represent a heterogeneous mix of cancer subtypes and that these subtypes have different disease patterns by race, sex, and age at diagnosis, studying all soft-tissue sarcomas combined may mask subtype-specific associations. Using the Selected Cancers Study, a large population-based case-control study of sarcoma conducted among U.S. men aged 30 to 60 in 1984 to 1988, we explored the occupational risk factors for soft-tissue sarcoma subtypes and skeletal sarcoma. The analysis included 251 living sarcoma cases (48 dermatofibrosarcoma protuberans, 32 malignant fibrohistiocytic sarcoma, 67 leiomyosarcoma, 53 liposarcoma, and 51 skeletal sarcoma) and 1908 living controls. Exact conditional logistic regression models suggested patterns of subtype specificity for occupational exposures. Self-reported herbicide use was associated with malignant fibrohistiocytic sarcoma (OR = 2.9, 95% CI = 1.1-7.3). We found elevated risks for chlorophenol exposure and cutting oil exposure and malignant fibrohistiocytic sarcoma and leiomyosarcoma. We found no occupational risk factor for liposarcoma. Polytomous regression models identified different odds ratios across subtypes for plywood exposure and exposure to wood and saw dust. Although exploratory, this analysis suggests that occupational risk factors for sarcoma are not uniform across subtypes.

Occupational chlorophenol exposure and soft tissue sarcoma risk among men aged 30-60 years.

To evaluate the association of chlorophenol exposure with soft tissue sarcoma risk independent of phenoxyherbicide exposure, the authors analyzed data from the Selected Cancers Study, a population-based case-control study that included 295 male soft tissue sarcoma cases, aged 32-60 years, from eight population-based cancer registries and 1,908 male controls. Chlorophenol exposure was assigned using both an intensity and a confidence estimate by an industrial hygienist based on verbatim job descriptions. Seventeen percent of the jobs rated as high intensity involved wood preservation, while 82% involved cutting oils. Soft tissue sarcoma risk, modeled using conditional logistic regression, was significantly associated with ever having high-intensity chlorophenol exposure (odds ratio = 1.79, 95% confidence interval 1.10-2.88). A duration-response trend was evident among more highly exposed subjects (p for trend < 0.0001). For subjects with 10 or more years of substantial exposure, the odds ratio was 7.78 (95% confidence interval 2.46-24.65). These results suggest that chlorophenol exposure independent of phenoxyherbicides may increase the risk of soft tissue sarcoma. Because of the large number of machinists in the exposed group and the complex composition of cutting fluids, it is possible that another exposure involved in machining is responsible for the observed excess risk.