Biomedical subjects

J A Baron

Publications and source records attributed to J A Baron.

At least 73 records · Page 4Linked to original sources

PubMed1998

Venous thromboembolism and cancer.

BACKGROUND: Although cancer has been clearly associated with venous thromboembolism (VTE), many aspects of this relation are poorly understood, including the cancer sites most affected and the cancer risk during long-term follow-up. To clarify these relations, we carried out a large, population-based analysis of VTE and cancer risk. METHODS: Using the Swedish Inpatient Register and linkage to the nationwide Cancer Registry, we assessed cancer incidence during 1989 among 61,998 patients without a previous cancer diagnosis admitted to hospital between 1965 and 1983 for VTE. To measure possible increases in cancer risk, we computed standardised incidence ratios (SIRs) using Swedish national cancer rates for the period of the study. FINDINGS: At the time of thromboembolic admission or during the first year of follow-up, 2509 cancers were diagnosed (SIR 4.4, 95% CI 4.2-4.6) [corrected]. The SIR for polycythaemia vera was 12.9 (8.6-18.7), and the SIRs for cancers of the liver, pancreas, ovary, and brain, and for Hodgkin lymphoma also exceeded 5.0. Patients aged less than 65 years had higher SIRs than those who were older. In subsequent years, 6081 cancers were diagnosed (1.3, 1.3-1.3). Even 10 years or more after admission to hospital with VTE, cancer incidence had increased (1.3, 1.3-1.4). INTERPRETATION: At the time of VTE or in the first year afterwards, we found a large increase in the risk for diagnosis of virtually all cancers. In subsequent years, a persistent 30% increase in risk remains. Either premalignant change promotes thrombosis, or cancer and thrombosis share common risk factors.

Cohort Studies↗

PubMed1998

Folate intake, alcohol consumption, cigarette smoking, and risk of colorectal adenomas.

BACKGROUND: Recent evidence suggests that folic acid (and derivatives) could contribute to the protective effect of fruits and vegetables against the risk of large-bowel cancer. Other evidence indicates that alcohol drinking and cigarette smoking may impair the biologic actions of folate. We used data from an adenoma prevention trial to investigate the occurrence of colorectal adenomas (possible precursors of colorectal cancer) in association with folate intake, alcohol consumption, and cigarette smoking. METHODS: Patients with at least one recent large-bowel adenoma were followed with colonoscopy 1 year and 4 years after their qualifying colon examinations. Adenomas detected after the year 1 examination were used as end points. A food-frequency questionnaire was administered at study entry and at study completion; nutrient intake at study entry was used in this analysis. All statistical tests were two-sided. RESULTS: After adjustment for caloric intake, dietary folate had a significant protective association with the risk of recurrence of large-bowel adenoma (P for trend = .04). However, this inverse association was attenuated by further adjustment for intake of dietary fiber and fat. Use of folate supplements was not associated with a reduction in risk. Alcohol intake (seven or more drinks/week) was associated with increased risk (odds ratio = 2.04; 95% confidence interval = 1.28-3.26). Cigarette smoking, even smoking for long duration, was not related to adenoma recurrence. CONCLUSIONS: These data provide only modest support for previous findings suggesting beneficial effects of folate on colorectal adenoma risk. We find no evidence that cigarette smoking increases risk. These findings do suggest a substantial increase in risk with alcohol consumption.

Adenoma↗

PubMed1998

Variation in the efficacy of hormone replacement therapy in the prevention of hip fracture. Swedish Hip Fracture Study Group.

Use of postmenopausal hormone replacement therapy (HRT) has been associated with a reduced risk of osteoporotic fractures. However, it is uncertain whether this risk reduction is modified by other risk factors for hip fracture. In a population-based case-control study in Sweden, we investigated the association between HRT and hip fracture risk within categories of age, body measures and lifestyle factors in postmenopausal women, 50-81 years of age. Mailed questionnaires and telephone interviews were used to collect data. Of those eligible, 1328 incident cases with hip fracture (82.5%) and 3312 randomly selected controls (81.6%) answered the questionnaire. Ever use of HRT in women less than 75 years old was associated with an odds ratio (OR) of 0.66 (95% confidence interval: 95% CI 0.50-0.87) for hip fracture compared with OR 0.40 (95% CI 0.21-0.77) in women 75 years or older. We found a significant interaction between HRT and both weight and physical activity (p < 0.05). The protective effect of HRT was particularly pronounced in lean women: compared with never HRT users, ever users weighing under 60 kg had an OR of 0.44 (95% CI 0.30-0.66) whereas women weighing more than 70 kg had an OR of 0.91 (95% CI 0.53-1.56). Women with low recent leisure physical activity (less than 1 h/week) similarly benefited more from HRT for hip fracture prevention than women with a higher degree of recreational physical activity. The observed interactions with weight and physical activity suggest that HRT has the best protective effect against hip fracture among high-risk women.

Age Factors↗

PubMed1998

Utilization of rheumatology physician services by the elderly.

PURPOSE: To examine rheumatology subspecialty practice patterns, determinants of referral to rheumatologists, and utilization of aspiration and injection procedures in a population-based sample of elderly individuals. SUBJECTS AND METHODS: We obtained Medicare physician claims for all visits to rheumatologists among beneficiaries aged 65 years and older in Colorado, Massachusetts, and Virginia in 1993, and for visits to all providers by patients with coded diagnoses of rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). We examined variations in visit frequency and aspiration/injection procedures, and we analyzed determinants of referral to a rheumatologist for RA or SLE. RESULTS: In 1 year, 144,797 visits were made to rheumatologists by 38,443 patients in the three states. An inflammatory disorder was coded in 45% of visits and a noninflammatory disorder in 50%. Half of patients with RA were seen three or fewer times in the year. For RA and SLE, African Americans were about 60% as likely to be seen by a rheumatologist as whites. Utilization of rheumatologist services for rheumatoid arthritis and systemic lupus erythematosus was highest in the state (Virginia) with the lowest per capita supply of rheumatologists. Among patients with bursitis, tendinitis, and osteoarthritis, African-American women were more likely to receive an injection or aspiration procedure than whites or African-American men. CONCLUSION: Elderly patients with rheumatologic disorders were seen by specialists less frequently than recommended by a recent rheumatology manpower survey. African-Americans with RA and SLE had fewer rheumatology visits than whites.

Aged↗

PubMed1998

Adenoma characteristics at first colonoscopy as predictors of adenoma recurrence and characteristics at follow-up. The Polyp Prevention Study Group.

BACKGROUND & AIMS: All patients with colorectal adenomas may not require identical follow-up. We aimed to determine if adenoma characteristics at initial colonoscopy could predict adenoma recurrence or characteristics at follow-up. METHODS: The number of adenomas and the size, type, and degree of atypia in 479 patients in a polyp prevention trial were evaluated as predictors of the same characteristics at follow-up using odds ratios (ORs) with 95% confidence intervals (CIs). Multiple logistic regression analysis was performed to determine if several baseline characteristics were simultaneously associated with outcome. RESULTS: Although several characteristics were significant predictors of recurrence univariately, by multivariate analysis, multiple adenomas at follow-up were more likely when patients had > or = 3 baseline adenomas (OR, 2.25; 95% CI, 1.20-4.21) or at least 1 tubulovillous adenoma (OR, 2.12; 95% CI, 1.12-4.02). No specific characteristic was associated with recurrence of high-risk polyps (> or = 1 cm, villous, severe atypia). Seventy percent of patients with 1 or 2 baseline adenomas had no recurrence, and only 3.3% had any adenomas of clinical concern. CONCLUSIONS: Number and type of baseline adenomas predict recurrent adenomas, but the recurrence is rarely of clinical concern. Patients with 1 or 2 tubular adenomas constitute a low-risk group for whom follow-up might be extended beyond 3 years.

Adenoma↗

PubMed1998

Design of an epidemiologic study of drinking water arsenic exposure and skin and bladder cancer risk in a U.S. population.

Ingestion of arsenic-contaminated drinking water is associated with an increased risk of several cancers, including skin and bladder malignancies; but it is not yet clear whether such adverse effects are present at levels to which the U.S. population is exposed. In New Hampshire, detectable levels of arsenic have been reported in drinking water supplies throughout the state. Therefore, we have begun a population-based epidemiologic case-control study in which residents of New Hampshire diagnosed with primary squamous cell (n = 900) and basal cell (n = 1200) skin cancers are being selected from a special statewide skin cancer incidence survey; patients diagnosed with primary bladder cancers (n = 450) are being identified through the New Hampshire State Cancer Registry. Exposure histories of these patients will be compared to a control group of individuals randomly selected from population lists (n = 1200). Along with a detailed personal interview, arsenic and other trace elements are being measured in toenail clipping samples using instrumental neutron activation analysis. Household water samples are being tested on selected participants using a hydride generation technique with high-resolution inductively coupled plasma mass spectrometry. In the first 793 households tested arsenic concentrations ranged from undetectable (0.01 microgram/l) to 180 microgram/l. Over 10% of the private wells contained levels above 10 microgram/l and 2.5% were above 50 microgram/l. Based on our projected sample size, we expect at least 80% power to detect a 2-fold risk of basal cell or squamous cell skin cancer or bladder cancer among individuals with the highest 5% toenail concentrations of arsenic.

Adult↗

PubMed1998

Occurrence of other cancers among patients with prior basal cell and squamous cell skin cancer.

Epidemiological studies suggest that individuals with basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) of the skin are more likely to develop other malignancies; however, the factors responsible for this are unknown. To clarify the risk of other cancers following the occurrence of BCC and SCC, we followed participants in a multicenter skin cancer prevention trial for subsequent malignancies. The study group consisted of 1805 BCC and SCC patients who had enrolled in a trial testing the efficacy of oral beta-carotene. Medical confirmation was sought for all cancers (other than BCC or SCC), which were reported by participants or their next-of-kin over a follow-up period of 10 years. We computed the rate ratio (RR) and 95% confidence interval (CI) of time to first new, primary cancer in relation to history of BCC and SCC, using a proportional hazards model. A total of 235 participants had a new primary invasive cancer during 13,887 person-years of follow up. The risk of other cancers was modestly elevated in patients with one or more previous SCCs compared with those who only had a history of BCC (adjusted RR, 1.37; 95% CI, 0.91-2.07). Risk of other cancers also appeared to be increased among those who had multiple prior BCCs relative to those who had only one prior BCC (adjusted RR, 1.21; 95% CI, 0.91-1.61). Further adjustment for smoking history, Quetelet index, radiotherapy, extent of actinic skin damage, treatment assignment, or baseline beta-carotene concentrations did not appreciably alter the results. Cancer of the respiratory system was most strongly related to previous SCC or multiple BCC [RRs (95% CI), 2.20 (1.05-4.62) and 2.34 (1.14-4.83), respectively]. Our data suggest that unidentified exposures or inherited risk factors may play a common etiological role in the pathogenesis of nonmelanoma skin cancer and other cancers, especially respiratory cancers, although larger studies would be necessary to exclude the role of chance in these findings.

Aged↗

PubMed1998

Dietary and supplemental calcium and the recurrence of colorectal adenomas.

The association between calcium intake and the risk of colorectal neoplasia remains controversial. This analysis prospectively investigated the association between dietary and supplemental calcium intake and recurrent colorectal adenomas. Participants were part of a multicenter, randomized clinical trial of antioxidant vitamins. The study endpoints were adenomas detected between surveillance colonoscopies conducted at approximately 1 year and 4 years after study entry. Baseline intake of energy-adjusted calcium derived from a food frequency questionnaire was used as the main exposure of interest. Calcium supplement use was assessed by semiannual questionnaires. Logistic regression was used to compute odds ratios and 95% confidence limits, and Poisson regression was used to estimate rate ratios. Subjects in the fifth quintile of dietary calcium had an adjusted odds ratio of 0.72 (95% confidence interval, 0.43-1.22) compared to those in the lowest quintile. Investigation of the numbers of adenomas yielded stronger findings: the rate ratio for the fifth quintile versus the first was 0.63 (95% confidence interval, 0.39-1.02). Dietary calcium seemed to have a greater effect among individuals with a high-fat diet than among those with a low-fat diet; however, the interaction was not statistically significant. Use of calcium supplements was not related to adenoma recurrence. These results suggest that a high calcium intake may be associated with a reduction in risk of recurrent adenomas, especially among individuals on a high-fat diet.

Adenoma↗

PubMed1998

Psychotropic medication use and risk of epithelial ovarian cancer.

Long-term use of psychotropic medication may increase the risk for epithelial ovarian cancer through increased gonadotropin secretion or direct ovarian stimulation of adrenergic receptors, effects which may affect ovarian cancer pathogenesis. An earlier case-control study found that prior use of antidepressants or benzodiazepine tranquilizers was associated with a 2-fold increase in risk of epithelial ovarian cancer. However, that study lacked details on all types of psychotropic medications, length of use, and the categorization of the specific action of these medications on the hypothalamic-pituitary-ovarian axis. In a new case-control study conducted in eastern Massachusetts (MA) and all of New Hampshire (NH), we identified all women with newly diagnosed ovarian cancer between May 1992 and March 1997. We interviewed 563 women diagnosed with malignant or borderline epithelial ovarian tumors and 523 controls identified through random digit dialing and the use of Town Books (residential listings by name, age, and precinct). Participants were asked to provide the name of medications used for 6 months or longer, the age at first use, and total months or years of use. Psychotropic medications included amphetamines, sedatives, barbiturates/anticonvulsants, antidepressants, and antipsychotics. Self-reported use of psychotropic medication for 6 months or longer was associated with a statistically significant increase in risk of invasive ovarian cancer [odds ratio (OR), 1.6; 95% confidence interval (CI), 1.1-2.3]. Relative to nonusers, risk was greatest in those whose first use occurred premenopausally for more than 2 years (OR, 2.9; CI, 1.3-6.6). The association was largely confined to use of medications that operate through dopaminergic mechanisms (OR, 2.9; CI, 1.3-6.4) or gabaergic pathways (OR, 1.5; CI, 0.9-2.5) as opposed to serotoninergic pathways (OR, 1.0; CI, 0.4-2.1). These results are consistent with the hypothesis that psychotropic medications induce gonadotropin secretion, which in turn may increase ovarian cancer risk. However, until other studies confirm our findings and determine whether they apply to medications with specific neuroendocrine actions, it is premature to advise a change in clinical practice and conclude that these medications indeed play a role in the etiology of ovarian cancer.

Adult↗

PubMed1997

Sensitivity and positive predictive value of Medicare Part B physician claims for rheumatologic diagnoses and procedures.

OBJECTIVE: To examine the sensitivity and positive predictive value of Medicare physician claims for select rheumatic conditions managed in rheumatology specialty practices. METHODS: Eight rheumatologists in 3 states abstracted 378 patient office records to obtain information on diagnosis and office procedures. The Medicare Part B physician claims for these patient visits were obtained from the Health Care Financing Administration. The sensitivity of the claims data for a specific diagnosis was calculated as the proportion of all patients whose office records for a particular visit documented that diagnosis and who also had physician claims for that visit which identified that diagnosis. The positive predictive value was evaluated in a separate sample of 331 patient visits identified in Medicare physician claims. The positive predictive value of the claims data for a specific diagnosis was calculated as the proportion of patients with that diagnosis coded in the claims for a particular visit who also had the diagnosis documented in the medical record for that visit. RESULTS: Ninety percent of abstracted office medical records were matched successfully with Medicare physician claims. The sensitivity of the Medicare physician claims was 0.90 (95% confidence interval [CI] 0.85-0.95) for rheumatoid arthritis (RA), 0.85 (95% CI 0.73-0.97) for systemic lupus erythematosus (SLE), and 0.85 (95% CI 0.78-1.0) for aspiration or injection procedures. The sensitivity for osteoarthritis (OA) of the hip or knee was < or = 0.50 if 5-digit codes specifying anatomic site were required. The sensitivity for fibromyalgia (FM) was 0.48 (95% CI 0.28-0.68). The positive predictive values were at least 0.90 for RA, SLE, and aspiration or injection procedures. Positive predictive values for FM and the 5-digit site-specific codes for OA of the knee were 0.83 (95% CI 0.66-1.0) and 0.88 (95% CI 0.75-1.0), respectively, while the positive predictive value of the 5-digit site-specific codes for OA of the hip was zero (95% CI 0-0.26). The positive predictive value of OA at any site was 0.83 (95% CI 0.76-0.90). CONCLUSION: In specialty practice, Medicare physician claims had high sensitivity and positive predictive value for RA, SLE, OA without specification of anatomic site, and injection or aspiration procedures. The claims had lower sensitivity and predictive value for FM and for OA of the hip. The accuracy of Medicare physician claims for other conditions and in the primary care setting requires further investigation.

Aged↗

PubMed1997

Physical activity in usual occupation and risk of breast cancer (United States).

We have used data from a large population-based case-control study in the United States to evaluate the effect of occupational physical activity on breast cancer risk. Women diagnosed with breast cancer identified from four state cancer registries, and controls randomly selected from lists of licensed drivers or Medicare beneficiaries, were interviewed by telephone for information on usual occupation and other factors. We classified usual occupation into one of four categories of physical activity. After excluding subjects for whom a strength rating could not be assigned, we had a final sample size of 4,863 cases and 6,783 controls. Using conditional logistic regression models, we calculated adjusted odds ratios (OR) and 95 percent confidence intervals (CI) for occupations having light, medium, and heavy activity compared with sedentary ones. Women with heavy-activity occupations had a lower risk of breast cancer than women with sedentary jobs (OR = 0.82, CI = 0.63-1.08), as did women with jobs with medium activity (OR = 0.86, CI = 0.77-0.97) or light activity (OR = 0.92, CI = 0.84-1.01). There was a significant decreasing trend in the ORs from sedentary to heavy work (P = 0.007). Although limited by exposure misclassification, these data are consistent with the hypothesis that physical activity reduces the risk of breast cancer.

Adult↗

PubMed1997

Effects of 4 y of oral supplementation with beta-carotene on serum concentrations of retinol, tocopherol, and five carotenoids.

beta-Carotene has been studied widely as a potential cancer-preventing agent. Recent studies found that subjects who took beta-carotene supplements orally had increases in their serum concentrations of alpha-carotene and lycopene that were large (> 150% increase) and significantly greater than such increases in subjects who received placebo and that similar supplementation was associated with a decrease of approximately 37% in plasma lutein concentrations. A biologic interaction between beta-carotene and other carotenoids was suggested. We measured concentrations of retinol, alpha-tocopherol, and five carotenoids in serum specimens from a random sample of subjects enrolled in a clinical trial of the use of antioxidant vitamins in preventing colonic adenomas. We used serum specimens obtained at enrollment and after the subjects took placebo (n = 54) or 25 mg beta-carotene/d (n = 54) orally for 4 y. In a multivariate analysis, baseline serum concentrations of the analytes, sex, body mass index, diet, smoking status, and age were associated with variable changes in some analytes over the 4-y period but supplementation with beta-carotene was related only to a mean increase in serum beta-carotene itself of 151%. We excluded with 95% confidence an increase in lycopene > 4.9%, an increase in alpha-carotene > 17.6%, and a decrease in lutein > 14.7% in subjects given beta-carotene. These results confirm previous findings that supplementation with beta-carotene given orally does not alter serum concentrations of retinol or alpha-tocopherol. The findings also indicate that beta-carotene supplementation, which results in a moderate increase in serum beta-carotene concentration, does not significantly change serum concentrations of other carotenoids.

Adult↗

PubMed1997

Coffee and tea and the risk of recurrent colorectal adenomas.

Consumption of coffee has been associated with a reduction in the risk of cancer of the colon, and (less consistently) drinking tea has been associated with a reduction in the risk of rectal cancer. The effect of these beverages on the risk of colorectal adenomas, however, has not been well investigated. We used data from an adenoma prevention trial to investigate these associations. Patients with at least one recent large bowel adenoma were followed with colonoscopy 1 and 4 years after their qualifying examinations. Adenomas detected at the year 4 colonoscopy were used as end points. A food frequency questionnaire was administered at study entry and study completion; average intake over the study period was used to estimate the exposures of interest. There was no apparent association between the intake of regular coffee, decaffeinated coffee, or tea and the risk of recurrent colorectal adenomas. The relative risks and 95% confidence intervals per cup daily were 0.96 (0.87-1.05) for regular coffee, 0.97 (0.84-1.12) for decaffeinated coffee, and 1.02 (0.83-1.25) for tea. These negative findings were present both overall and for adenomas of the right and left large bowel.

Adenoma↗

PubMed1997

Risk of squamous cell carcinoma of the skin in relation to plasma selenium, alpha-tocopherol, beta-carotene, and retinol: a nested case-control study.

We conducted a nested case-control study of squamous cell skin cancer (SCC) to determine whether risk was related to plasma concentrations of selenium, alpha-tocopherol, beta-carotene, and retinol. We derived the study sample from participants in our Skin Cancer Prevention Study, all of whom had at least one basal cell or squamous cell skin cancer before study entry. Those who developed a new squamous cell skin cancer during the 3-5-year follow-up period were selected as cases (n = 132). Controls (n = 264) were chosen at random, with matching by age, sex, and study center, from among those who did not develop SCC but were being followed actively at the time the SCC case was diagnosed. Prediagnostic plasma samples were analyzed for alpha-tocopherol, beta-carotene, and retinol using high-performance liquid chromatography. Selenium determinations were made using instrumental neutron activation analysis. Odds ratios were computed using conditional logistic regression for matched samples. We found no consistent pattern of SCC risk associated with any of the nutrients examined. The odds ratios (95% confidence intervals) for the highest versus the lowest quartiles of beta-carotene, retinol, alpha-tocopherol, and selenium were 0.73 (0.38-1.41), 1.43 (0.77-2.64), 0.89 (0.43-1.85), and 0.86 (0.47-1.58), respectively. Thus, our data add to the growing body of evidence that these nutrients, at the concentrations we evaluated, are not related strongly to SCC risk.

Adult↗

PubMed1997

Dietary iron and recurrence of colorectal adenomas.

Previous research suggests that iron acts as a prooxidant to increase the risk of colorectal neoplasia. This study examined effects of dietary intake of iron on colorectal adenoma recurrence using data from an antioxidant clinical trial. All subjects were free of polyps at study entry but had at least one adenoma removed within the 3 months before enrollment. Follow-up colonoscopies were conducted after 1 and 4 years. Patients who developed one or more adenomatous polyps between years 1 and 4 were classified as cases; all others were controls. Dietary iron intake at baseline and at the end of the study was estimated from self-administered food frequency questionnaires and averaged together for each subject, energy-adjusted, and categorized into quartiles. Odds ratios were adjusted for age, center, sex, calories, treatment group, and alcohol, fiber, folate, and fat intakes in unconditional logistic regression analysis. Dietary iron was inversely associated with adenoma risk, although risk did not decrease monotonically with increasing intake. Odds ratios comparing second, third, and fourth quartiles to the lowest quartile were 0.61 [95% confidence interval (CI), 0.37-1.02], 0.80 (95% CI, 0.45-1.44), and 0.37 (95% CI, 0.19-0.73), respectively. A limited examination showed no clear evidence that use of iron supplements affected risk of recurrence in this study population. This study provides evidence against the hypothesis that recent dietary intake of iron increases risk for colorectal adenomas. However, these results may reflect the presence of other dietary factors found in combination with iron.

Adenoma↗

PubMed1996

Risk of basal cell and squamous cell skin cancers after ionizing radiation therapy. For The Skin Cancer Prevention Study Group.

BACKGROUND: Human evidence that ionizing radiation is carcinogenic first came from reports of nonmelanoma skin cancers (NMSCs) on the hands of workers using early radiation devices. An increased risk of NMSC has been observed among uranium miners, radiologists, and individuals treated with x rays in childhood for tinea capitis (ringworm of the scalp) or for thymic enlargement; NMSC is one of the cancers most strongly associated with the atomic bombing of Hiroshima and Nagasaki. Although exposure to ionizing radiation is a known cause of NMSC, it is not yet clear whether therapeutic radiation causes both major histologic types of NMSC, basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). Additionally, the potentially modifying effects, such as latency, age when treated, and type of treatment, are not well understood. PURPOSE: We investigated the relative risks of BCC and SCC associated with previous radiation therapy and evaluated these risks in relation to age and time since initial treatment and the medical condition for which radiation therapy was given. METHODS: The study group comprised individual diagnosed with at least one BCC or SCC from January 1980 through February 1986, who were recruited to participate in a skin cancer prevention trial designed to test whether oral beta-carotene supplementation would reduce the risk of new NMSCs. Patients were identified through the dermatology and pathology records of academic medical centers in Hanover, NH; Los Angeles, CA; San Francisco, CA; and Minneapolis, MN. Each participant completed a questionnaire detailing lifetime residence, pigmentary characteristics, occupational and recreational sun exposure, and history of radiation therapy. At enrollment, a study dermatologist assessed skin type (tendency to burn or tan) and extent of actinic skin damage. Participants were followed with an annual dermatologic examination for an average of 4 years. Of the 5232 potentially eligible individuals, 1805 were enrolled in the trial. We excluded 112 patients who reported previous radiation therapy for skin cancer only and three with missing information on whether they were ever treated with radiation therapy, leaving 1690 patients for the analysis. Approximately 4% of the patients died or discontinued participation for other reasons during each study year. We examined time to occurrence of first new histopathologically confirmed BCC and SCC during the follow-up period in relation to history of radiation therapy (for reasons other than NMSC) using a proportional hazards model. A multiple end points survival model was used to compare the rate ratios (RRs) for BCC and SCC. We also used a longitudinal method of analysis to compute the RR of total new BCC and SCC tumors per person per study year associated with radiation therapy. Using this method, we additionally assessed the potential modifying effects of age at treatment, latency, and type of therapy. All P values were derived from two-sided statistical tests of significance. RESULTS: Among the participants we studied, 597 developed a new BCC (n = 1553 tumors) and 118 developed a new SCC (n = 179 tumors). The time to first new BCC, but not SCC, was associated with prior radiation therapy (RR = 1.7; 95% confidence interval [CI] = 1.4-2.0 and RR = 1.0; 95% CI = 0.6-1.7, respectively; P = .03 for the difference between the RRs). The RR of total BCC tumors was slightly higher (RR = 2.3; 95% CI = 1.7-3.1), but it was still unity for SCC (RR = 1.0; 95% CI = 0.5-1.9). BCC risk appeared to increase with younger age at exposure and time since initially treated, although these effects were only marginally statistically significant (P for trend = .06 and .07, respectively). Also, risk of BCC was more strongly related to treatment for acne (RR = 3.3; 95% CI = 2.1-5.2) than other conditions. CONCLUSIONS AND IMPLICATIONS: Our data suggest that exposure to therapeutic radiation is associated with BCC but not with SCC.

Adult↗

PubMed1996

Trends in non-epithelial cancer incidence in Denmark, Finland, and Sweden, 1961-1990.

Trends in the incidence of non-epithelial cancers are particularly likely to reflect environmental carcinogens, since these malignancies are not commonly the targets of screening efforts, and have generally not been closely associated with life style factors such as cigarette smoking and diet. We used data from nation-wide cancer registries in Denmark, Finland, and Sweden to examine trends in non-epithelial cancers over the period 1961-1990. Linear regression analysis of age-standardized rates, and age-period-cohort models were fit to assess the temporal patterns within each country. Within each of the 3 countries, there was a similarly increasing incidence of both hematological malignancies and nervous system/bone/soft-tissue neoplasms. The increases were smallest in children and adolescents (ages 0-14), moderate among young and middle aged adults (ages 15-64), and most pronounced among the elderly (ages 65+). Age-period-cohort modeling suggested that the dominant factor in the increases were birth cohort effects. It is not clear what factors underlie this increase in incidence; it seems most likely that increases both in diagnostic efficiency and in exposure to environmental carcinogens play a role.

Adolescent↗

PubMed1996

Jewish religion and risk of breast cancer.

BACKGROUND: The excess risk of breast cancer among Jewish women has been attributed to the effects of difference in lifestyle and reproductive patterns, but there is now evidence that Jewish women may be more likely than other women to inherit mutations in breast-cancer genes. We investigated whether any excessive risk among Jewish women is confined to those with a family history of breast cancer. METHODS: We assessed the effect of Jewish religion on breast cancer in a large population-based case-control study (6611 women with breast cancer and 9026 controls) in USA. Participants were given telephone interviews and asked about known and suspected risk factors for breast cancer. FINDINGS: Overall, Jewish women had only a slightly raised relative risk of breast cancer (1.10 [95% CI 0.84-1.44]; p=0.49). However, the relative risk was much higher for Jewish women with a first-degree relative who had breast cancer (3.78 [1.74-8.16]; p<0.001). The effect of family history was greater in Jewish women than in women of other religions (p interaction = 0.05). INTERPRETATION: These results are consistent with data suggesting that certain groups of Jewish women have a higher than expected rate of mutation in the breast-cancer gene BRCA1.

Aged↗