Search

Background: Knowledge of family cancer history is essential for estimating an individual's cancer risk and making clinical recommendations regarding screening and referral to a specialty cancer genetics clinic. However, it is not clear if reported family cancer history is sufficiently accurate for this purpose., Methods: In the population-based 2001 Connecticut Family Health Study, 1019 participants reported on 20 578 first-degree relatives (FDR) and second-degree relatives (SDR). Of those, 2605 relatives were sampled for confirmation of cancer reports on breast, colorectal, prostate, and lung cancer. Confirmation sources included state cancer registries, Medicare databases, the National Death Index, death certificates, and health-care facility records. Sensitivity, specificity, positive predictive value, and negative predictive value were calculated for reports on lung, colorectal, breast, and prostate cancer and after stratification by sex, age, education, and degree of relatedness and used to estimate report accuracy. Pairwise t tests were used to evaluate differences between the two strata in each stratified analysis. All statistical tests were two-sided., Results: Overall, sensitivity and positive predictive value were low to moderate and varied by cancer type: 60.2% and 40.0%, respectively, for lung cancer reports, 27.3% and 53.5% for colorectal cancer reports, 61.1% and 61.3% for breast cancer reports, and 32.0% and 53.4% for prostate cancer reports. Specificity and negative predictive value were more than 95% for all four cancer types. Cancer history reports on FDR were more accurate than reports on SDR, with reports on FDR having statistically significantly higher sensitivity for prostate cancer than reports on SDR (58.9% vs 21.5%, P = .002) and higher positive predictive value for lung (78.1% vs 31.7%, P < .001), colorectal (85.8% vs 43.5%, P = .004), and breast cancer (79.9% vs 53.6%, P = .02)., Conclusions: General population reports on family history for the four major adult cancers were not highly accurate. Efforts to improve accuracy are needed in primary care and other health-care settings in which family history is collected to ensure appropriate risk assessment and clinical care recommendations.

Background: Blood transfusions may influence the recipients' cancer risks both through transmission of biologic agents and by modulation of the immune system. However, cancer occurrence in transfusion recipients remains poorly characterized., Methods: We used computerized files from Scandinavian blood banks to identify a cohort of 888,843 cancer-free recipients transfused after 1968. The recipients were followed from first registered transfusion until the date of death, emigration, cancer diagnosis, or December 31, 2002, whichever came first. Relative risks were expressed as ratios of the observed to the expected numbers of cancers, that is, standardized incidence ratios (SIRs), using incidence rates for the general Danish and Swedish populations as a reference. All statistical tests were two-sided., Results: During 5,652,918 person-years of follow-up, 80,990 cancers occurred in the transfusion recipients, corresponding to a SIR of 1.45 (95% confidence interval [CI] = 1.44 to 1.46). The SIR for cancer overall decreased from 5.36 (95% CI = 5.29 to 5.43) during the first 6 months after transfusion to 1.10 or less for follow-up periods more than 2 years after the transfusion. However, the standardized incidence ratios for cancers of the tongue, mouth, pharynx, esophagus, liver, and respiratory and urinary tracts and for squamous cell skin carcinoma remained elevated beyond 10 years after the transfusion., Conclusions: The marked increase in cancer risk shortly after a blood transfusion may reflect the presence of undiagnosed occult cancers with symptoms that necessitated the blood transfusion. The continued increased risk of tobacco- and alcohol-related cancers suggests that lifestyle and other risk factors related to conditions prompting transfusion rather than transfusion-related exposures per se are important to the observed cancer occurrence in the recipients.

Growing knowledge about gene-disease associations will lead to new opportunities for genetic testing. Many experts predict that genetic testing will become increasingly important as a guide to prevention, clinical management, and drug treatment based on genetic susceptibilities. As part of a Human Genetic Epidemiology workshop convened by the Centers for Disease Control and Prevention, a group of experts evaluated the evidence needed when considering the appropriate use of new genetic tests. Because new tests are likely to vary in their predictive value, their potential to direct prevention or treatment efforts, and their personal and social consequences, the task of determining appropriate use will require careful consideration of a variety of factors, including the analytic validity, clinical validity, clinical utility, and ethical, legal, and social implications of the test. Standardized formats are needed to summarize what is known and not known about new genetic tests with respect to each of these features. Following criteria for the objective assessment of test properties, reports should be structured to enable policy makers, clinicians, and the public to identify the available evidence, so that uncertainties can be taken into account when considering test use and planning future research.

Serum IgG antibodies to human papillomavirus (HPV) types 16, 18, 31, and 45 virus-like particles were measured in a nested case-control study of cervical squamous intraepithelial lesions. HPV-16 seroreactivity was strongly associated with HPV-16 DNA detection (odds ratio, 9.0; 95% confidence interval, 4.4-19.4), and similar type specificity was observed for HPV-31 and -45. In contrast, seroreactivity to any type was associated with elevated seroreactivity to all others. Among cases and controls, HPV-16 showed the highest seroprevalence, with 23.8% of 80 cases and 10.5% of 258 controls seroreactive to HPV-16 alone, and another 27.5% and 5.4%, respectively, seroreactive to HPV-16 plus other types. Overall, 24 (30.0%) cases and 17 (6.6%) controls were seroreactive to multiple types. These data suggest that seroreactivity to a given type reflects mainly type-specific HPV infection as measured by DNA detection and may also signal past exposure to other types that are now only serologically detected.

Background: Diabetes has been associated with an increased risk of several cancers, notably cancers of the pancreas, liver, endometrium, and kidney. Since most previous studies have involved a limited sample size or focused on specific cancer sites, we conducted a comprehensive assessment of the risk of cancer in a nationwide cohort of diabetics in Denmark., Methods: Discharge records of 109581 individuals hospitalized with a diagnosis of diabetes from 1977 through 1989 were linked with national cancer registry records through 1993. Standardized incidence ratios (SIRs) were calculated for specific cancer sites., Results: The SIRs for primary liver cancer were 4.0 (95% confidence interval [CI] = 3.5-4.6) in males and 2.1 (95% CI = 1.6-2.7) in females. These SIRs remained elevated with increasing years of follow-up and after exclusion of patients with reported risk factors (e.g., cirrhosis and hepatitis) or patients whose cancers were diagnosed at autopsy. Kidney cancer risk was also elevated, with SIRs of 1.4 (95% CI = 1.2-1.6) in males and 1.7 (95% CI = 1.4-1.9) in females. For both sexes combined, the SIR for pancreatic cancer was 2.1 (95% CI = 1.9-2.4), with a follow-up time of 1-4 years; this SIR declined to 1.3 (95% CI = 1.1-1.6) after 5-9 years of follow-up. Excess risks were also observed for biliary tract and endometrial cancers. The SIRs for kidney and endometrial cancers declined somewhat after exclusion of diabetics with reported obesity., Conclusions: Patients hospitalized with a diagnosis of diabetes appear to be at higher risk of developing cancers of the liver, biliary tract, pancreas, endometrium, and kidney. The elevated risks of endometrial and kidney cancers, however, may be confounded by obesity.

The epidemiologic determinants of seroreactivity to human papillomavirus (HPV) type 16 L1/L2 virus-like particles (VLPs) were assessed separately in HPV-16 DNA-positive and -negative women participating in a nested case-control study of incident cervical neoplasia. Seventy-four women with cervical HPV-16 DNA and 656 cytologically normal HPV-16 DNA-negative subjects were interviewed and tested at two time points for viral DNA and once (at the later time) for VLP seroreactivity. Among subjects who were currently HPV-16 DNA-negative, seroreactivity odds ratios increased from 2.9 for 2-5 male sex partners (vs. 0 or 1) to 5.4 for 6-9 partners and 14.0 for > or = 10. Thus, prior cervical infection may be a major determinant of seroreactivity in HPV-16 DNA-negative women. This trend was not observed in HPV-16 DNA-positive subjects. Seroreactivity was independently associated with oral contraceptive use, particularly in HPV-16 DNA-negative subjects with use for > or = 10 years. Consequently, a possible role for virus-steroid hormone interactions in seroconversion is suggested.

An ELISA to detect serum IgG antibody response to human papillomavirus (HPV) type 16 virus-like particles (VLPs) was evaluated in a case-control study of cervical neoplasia, nested within a prospective cohort study. Subjects included 688 controls with continued normal cytology and 152 cases with confirmed incident squamous intraepithelial lesions who were tested for DNA for a broad spectrum of HPV types at cohort and follow-up of controls, 16.6% were seropositive compared with 30.8% and 52.4% of cases with low- and high-grade lesions, respectively. Of HPV-16 DNA-negative subjects, 16.5% were seropositive. Seropositivity increased from 22.2% in subjects who were HPV-16 DNA-positive by polymerase chain reaction once only (enrollment or follow-up) to 83.3% in those who were HPV-16 DNA-positive at both time points. These data imply that serum antibody to HPV-16 VLPs is a relatively sensitive indicator of persisting cervical HPV-16 infection.