Aspirin and the risk of colorectal cancer in women

BACKGROUND

Most data suggest that the regular use of aspirin reduces the risk of colorectal cancer, but some apparently conflicting evidence exists. The effects of the dose and the duration of aspirin consumption on the risk of colorectal cancer are not well understood.

METHODS

We determined rates of colorectal cancer according to the number of consecutive years of regular aspirin use (defined as two or more tablets per week) among women in the Nurses' Health Study who reported regular aspirin use on three consecutive questionnaires (1980, 1982, and 1984) and compared the rates in this group with the rates among women who said they did not use aspirin. Cases of cancer occurring from 1984 through 1992 (the eight years after the 1984 questionnaire) were included.

RESULTS

From 1984 through 1992, we documented 331 new cases of colorectal cancer during 551,651 person-years of follow-up. Women who consistently took two or more aspirin tablets per week had no appreciable reduction in the risk of colorectal cancer as compared with nonusers after four years (relative risk, 1.06; 95 percent confidence interval, 0.78 to 1.45) or after five to nine years (relative risk, 0.84; 95 percent confidence interval, 0.55 to 1.28). There was a slight reduction in risk among women who took aspirin for 10 to 19 years, but it was not statistically significant (relative risk, 0.70; 95 percent confidence interval, 0.41 to 1.20). However, there was a statistically significant reduction after 20 years of consistent use of aspirin (relative risk, 0.56; 95 percent confidence interval, 0.36 to 0.90; P for trend = 0.008). The maximal reduction in risk was observed among women who took four to six tablets per week; higher doses had a similar apparent benefit. Controlling for risk factors for colorectal cancer, including diet, did not change the results, and the earlier diagnosis and removal of colorectal adenomas among aspirin users did not account for the results.

CONCLUSIONS

Regular aspirin use, at doses similar to those recommended for the prevention of cardiovascular disease, substantially reduces the risk of colorectal cancer. However, this benefit may not be evident until after at least a decade of regular aspirin consumption.

Prediction of breast cancer risk based on profiling with common genetic variants

BACKGROUND

Data for multiple common susceptibility alleles for breast cancer may be combined to identify women at different levels of breast cancer risk. Such stratification could guide preventive and screening strategies. However, empirical evidence for genetic risk stratification is lacking.

METHODS

We investigated the value of using 77 breast cancer-associated single nucleotide polymorphisms (SNPs) for risk stratification, in a study of 33 673 breast cancer cases and 33 381 control women of European origin. We tested all possible pair-wise multiplicative interactions and constructed a 77-SNP polygenic risk score (PRS) for breast cancer overall and by estrogen receptor (ER) status. Absolute risks of breast cancer by PRS were derived from relative risk estimates and UK incidence and mortality rates.

RESULTS

There was no strong evidence for departure from a multiplicative model for any SNP pair. Women in the highest 1% of the PRS had a three-fold increased risk of developing breast cancer compared with women in the middle quintile (odds ratio [OR] = 3.36, 95% confidence interval [CI] = 2.95 to 3.83). The ORs for ER-positive and ER-negative disease were 3.73 (95% CI = 3.24 to 4.30) and 2.80 (95% CI = 2.26 to 3.46), respectively. Lifetime risk of breast cancer for women in the lowest and highest quintiles of the PRS were 5.2% and 16.6% for a woman without family history, and 8.6% and 24.4% for a woman with a first-degree family history of breast cancer.

CONCLUSIONS

The PRS stratifies breast cancer risk in women both with and without a family history of breast cancer. The observed level of risk discrimination could inform targeted screening and prevention strategies. Further discrimination may be achievable through combining the PRS with lifestyle/environmental factors, although these were not considered in this report.

Incidence and risk factors for cholangiocarcinoma in primary sclerosing cholangitis

Cholangiocarcinoma (CCA) is a dreaded complication of primary sclerosing cholangitis (PSC); however, marked variability in the incidence of CCA in PSC is reported. Furthermore, limited information exists on risk factors for the development of CCA in PSC. The aim of this study was to determine the incidence of CCA in patients with PSC and to evaluate baseline risk factors for the later development of CCA. From a previous study of the natural history of PSC, we identified 161 patients with PSC who did not have CCA at study entry. Patients were followed until a diagnosis of CCA was established, liver transplantation was performed, or death occurred. Patients were followed for a median of 11.5 yr (interquartile range 4.0-16.1 yr). Fifty-nine patients (36.6%) died, 50 patients (31.1%) underwent liver transplantation, and 11 patients (6.8%) developed CCA. The rate of CCA developing was approximately 0.6% per year. Compared to the incidence rates of CCA in the general population, the relative risk of CCA in PSC was significantly increased (RR = 1,560; 95%CI = 780, 2,793; p < 0.0001). On univariate analysis, a history of variceal bleeding (p < 0.001), proctocolectomy (p= 0.01), and lack of symptoms (p= 0.02) were significant risk factors for CCA with the Mayo Risk Score being marginally significant (p= 0.051). Multivariate analysis determined only variceal bleeding to be a significant risk factor for CCA (RR 24.2; 95%CI: 3.3-67.1). No association was found between the duration of PSC and the incidence of CCA. In conclusion, approximately 7% of PSC patients later developed CCA over a mean follow-up of 11.5 yr, which is dramatically higher than the rates in the general population. Variceal bleeding is a major risk factor for the later development of CCA.

Epidemiologic aspects of uveal melanoma

Although the underlying cause or causes of uveal melanoma have yet to be elucidated, important insights may be gained by examining the epidemiologic features of the disease. Uveal melanoma is an uncommon cancer with an incidence of only six cases per million population per year. It is most often diagnosed in the sixth decade and is somewhat more common in males. Apart from sporadic reports of family clusters, uveal melanoma is not considered an inherited disease. Whether some environmental exposure triggers the development of uveal melanoma remains an open question. Sunlight has been proposed as an environmental risk factor because sunlight is known to cause melanoma of the skin and both diseases are rare in nonwhite races. Unlike cutaneous melanoma, however, rates have not been increasing over time and do not vary by latitude. This paper evaluates the available evidence for sunlight and other potential risk factors for uveal melanoma, highlighting areas requiring further research.

Physical activity and survival after diagnosis of invasive breast cancer

Previous studies suggest that increased physical activity may lower the risk of breast cancer incidence, but less is known about whether levels of physical activity after breast cancer diagnosis can influence survival. We prospectively examined the relation between postdiagnosis recreational physical activity and risk of breast cancer death in women who had a previous invasive breast cancer diagnosed between 1988 and 2001 (at ages 20-79 years). All women completed a questionnaire on recent postdiagnosis physical activity and other lifestyle factors. Among 4,482 women without history of recurrence at the time of completing the questionnaire, 109 died from breast cancer within 6 years of enrollment. Physical activity was expressed as metabolic equivalent task-hours per week (MET-h/wk); hazard ratios (HR) and 95% confidence intervals (95% CI) were estimated using Cox proportional hazards regression. After adjusting for age at diagnosis, stage of disease, state of residence, interval between diagnosis and physical activity assessment, body mass index, menopausal status, hormone therapy use, energy intake, education, family history of breast cancer, and treatment modality compared with women expending <2.8 MET-h/wk in physical activity, women who engaged in greater levels of activity had a significantly lower risk of dying from breast cancer (HR, 0.65; 95% CI, 0.39-1.08 for 2.8-7.9 MET-h/wk; HR, 0.59; 95% CI, 0.35-1.01 for 8.0-20.9 MET-h/wk; and HR, 0.51; 95% CI, 0.29-0.89 for > or =21.0 MET-h/wk; P for trend = 0.05). Results were similar for overall survival (HR, 0.44; 95% CI, 0.32-0.60 for > or =21.0 versus <2.8 MET-h/wk; P for trend <0.001) and were similar regardless of a woman's age, stage of disease, and body mass index. This study provides support for reduced overall mortality and mortality from breast cancer among women who engage in physical activity after breast cancer diagnosis.

Survival of patients with metastases from uveal melanoma

The authors evaluated a series of 145 consecutive patients with metastases from uveal melanoma, after proton beam irradiation, to assess the effect of early diagnosis and treatment for metastases on survival. Metastases were diagnosed between 7 weeks and 8.3 years (median, 2.4 years) after proton beam irradiation. Most patients (n = 94) were symptomatic before diagnosis; the remainder were first detected during screening examination. Liver involvement was documented in nearly all patients (n = 136). The majority of patients had died from metastases by the close of the study (n = 137). Significantly longer survival occurred among patients diagnosed during screening examination (P = 0.004) and among young patients (P = 0.03). The majority of patients received some form of treatment for metastases (69%). Median survival was 2.0 months for patients receiving no treatment compared with 5.2 months for those receiving treatment for metastases (P = .0001). However, the overall 1-year survival rate was poor (13%). Prophylactic adjuvant therapy could be explored as a means to increase disease-free survival in patients with uveal melanoma.

Current approaches to the treatment of metastatic brain tumours

Metastatic tumours involving the brain overshadow primary brain neoplasms in frequency and are an important complication in the overall management of many cancers. Importantly, advances are being made in understanding the molecular biology underlying the initial development and eventual proliferation of brain metastases. Surgery and radiation remain the cornerstones of the therapy for symptomatic lesions; however, image-based guidance is improving surgical technique to maximize the preservation of normal tissue, while more sophisticated approaches to radiation therapy are being used to minimize the long-standing concerns over the toxicity of whole-brain radiation protocols used in the past. Furthermore, the burgeoning knowledge of tumour biology has facilitated the entry of systemically administered therapies into the clinic. Responses to these targeted interventions have ranged from substantial toxicity with no control of disease to periods of useful tumour control with no decrement in performance status of the treated individual. This experience enables recognition of the limits of targeted therapy, but has also informed methods to optimize this approach. This Review focuses on the clinically relevant molecular biology of brain metastases, and summarizes the current applications of these data to imaging, surgery, radiation therapy, cytotoxic chemotherapy and targeted therapy.

Body mass index before and after breast cancer diagnosis: associations with all-cause, breast cancer, and cardiovascular disease mortality

BACKGROUND

Factors related to improving outcomes in breast cancer survivors are of increasing public health significance. We examined postdiagnosis weight change in relation to mortality risk in a cohort of breast cancer survivors.

METHODS

We analyzed data from a cohort of 3,993 women with ages 20 to 79 years living in New Hampshire, Massachusetts, or Wisconsin with invasive nonmetastatic breast cancers diagnosed in 1988 to 1999 identified through state registries. Participants completed a structured telephone interview 1 to 2 years after diagnosis and returned a mailed follow-up questionnaire in 1998 to 2001 that addressed postdiagnosis weight and other factors. Vital status information was obtained from the National Death Index through December 2005. Hazard ratios and 95% confidence intervals were estimated from Cox proportional hazards models and adjusted for prediagnosis weight, age, stage, smoking, physical activity, and other important covariates.

RESULTS

During an average 6.3 years of follow-up from the postdiagnosis questionnaire, we identified 421 total deaths, including 121 deaths from breast cancer and 95 deaths from cardiovascular disease. Increasing postdiagnosis weight gain and weight loss were each associated with greater all-cause mortality. Among women who gained weight after breast cancer diagnosis, each 5-kg gain was associated with a 12% increase in all-cause mortality (P = 0.004), a 13% increase in breast cancer-specific mortality (P = 0.01), and a 19% increase in cardiovascular disease mortality (P = 0.04). Associations with breast cancer mortality were not modified by prediagnosis menopausal status, cigarette smoking, or body mass index.

CONCLUSION

These findings suggest that efforts to minimize weight gain after a breast cancer diagnosis may improve survival.

Hormone replacement therapy and risk of breast cancer: results from epidemiologic studies

OBJECTIVE

We combined data from published reports of the relation between estrogen use and breast cancer. We specifically addressed the hypothesis that the addition of progestins to estrogen therapy reduces the risk of breast cancer.

STUDY DESIGN

A meta-analysis was performed.

RESULTS

Replacement hormone therapy is not associated with increased risk of breast cancer in women who have ever used it (relative risk 1.02, 95% confidence interval 0.93 to 1.12). However, current use is associated with increased risk (relative risk 1.40, 95% confidence interval 1.20 to 1.63). Although there was no significant trend with increasing duration of use, women with > or = 10 years of estrogen use had a relative risk of 1.23 (95% confidence interval 1.08 to 1.40). However, data on use of estrogen plus progestins combined from four studies indicate that risk is not reduced and that the overall relative risk is 1.13 (95% confidence interval 0.78 to 1.64). Further, risk did not vary in strata of family history or benign breast disease.

CONCLUSION

Although these results exclude a large effect of hormone therapy on risk of breast cancer, we are unable to rule out some risk associated with current or long-term estrogen use.

Long-term results of proton beam irradiated uveal melanomas

The first 128 consecutive patients with uveal melanomas treated with proton beam irradiation were studied in order to evaluate survival and visual acuity status of patients with relatively long-term follow-up. The median follow-up was 5.4 years, and no patient was lost to follow-up. All tumors showed regression. The most recent visual acuity was 20/40 or better in 35% and 20/100 or better in 58%. Eight eyes were enucleated because of complications. Metastasis developed in 26 patients (20.5%) from 3 months to 7 years after treatment. Results indicate that proton irradiation is quite successful for achieving local control of uveal melanomas. A large proportion of the treated eyes maintained useful vision. Five-year follow-up data indicate that proton irradiation has no deleterious effect on the likelihood of the development of metastasis.

Ocular blood flow velocity in age-related macular degeneration

BACKGROUND

Changes in the structure of the ocular blood vessels associated with age-related macular degeneration (AMD) have been described in some detail, but comparatively little is known of the concomitant circulatory changes. The goal of this study is to evaluate changes in the ocular circulation that may be associated with AMD.

METHODS

Ocular blood flow velocities and vessel pulsatilities were measured in volunteers with and without AMD using a color Doppler imaging unit. Spectral analyses were recorded from the ophthalmic artery, central retinal artery and vein, the temporal and nasal short posterior ciliary arteries, and the four vortex veins.

RESULTS

Adjusting for age, pulsatility indices of all arteries were higher in subjects with AMD (central retinal artery [P = 0.02]; temporal and nasal short posterior ciliary arteries [P = 0.06 and 0.002, respectively]; and ophthalmic artery [P = 0.24]). End-diastolic blood flow velocity of the short posterior ciliary arteries tended to decrease in the presence of AMD.

CONCLUSIONS

The combination of increased pulsatility and decreased velocity of the short posterior ciliary arteries, observed in the presence of AMD, are interpreted as evidence of increased vascular resistance. The clinical signs of AMD may be related to degradation of the metabolic transport function of the retinal pigment epithelium, resulting from impaired choroidal perfusion.

Chronic pain: lifetime psychiatric diagnoses and family history

Thirty-seven patients with chronic pain admitted to a 3-week inpatient pain program were interviewed using the NIMH Diagnostic Interview Schedule and the family history method. The most frequent psychiatric diagnoses were major depressive disorder (current episode = 32.4%, past episode = 43.2%) and alcohol abuse (40.5%). More than half of the patients had a history of one or more episodes of major depression and/or alcohol abuse before the onset of their chronic pain. Family history revealed that 59.5% of the patients had at least one first-degree family member with chronic pain, 29.7% had a family member with affective illness, and 37.8% had a family member with alcohol abuse.

From menarche to menopause: trends among US Women born from 1912 to 1969

The authors investigated secular trends in age at menarche, age at menopause, and reproductive life span within a population-based cohort of US women. Study subjects were 22,774 women selected randomly as controls for a case-control study. Eligible controls were residents of Wisconsin, Massachusetts, or New Hampshire born between 1910 and 1969. Subjects completed telephone interviews in 1988-2001 and answered questions regarding reproductive and lifestyle factors. Birth cohorts were created using 5- and 10-year periods, and statistical comparisons were performed with analysis of variance. The mean age at menarche decreased by approximately 6 months for those born between 1910 and 1949 (13.1 vs. 12.7 years; p < 0.001), with a subsequent increase to 13.0 years among women born between 1960 and 1969 (p < 0.001). Among naturally menopausal women aged 60 or more years who reported never use of postmenopausal hormone therapy, the authors observed a 17-month increase in the mean age at menopause for those born between 1915 and 1939 (49.1 vs. 50.5 years; p = 0.001) after adjustment for potential confounders. They also observed an increase in the average number of reproductive years (subtracting age at menarche from age at natural menopause), from 36.1 years among women born between 1915 and 1919 to 37.7 years among the 1935-1939 cohort (p = 0.0001). These findings have implications for women's lifetime exposure to circulating endogenous hormones.

Family history is a significant risk factor for pancreatic cancer: results from a systematic review and meta-analysis

Epidemiologic evidence suggests a family history of pancreatic cancer (PC) is a risk factor for the disease, yet the magnitude of risk varies between studies. We performed a systematic review of studies that quantified familial risks of PC, and through a meta-analysis, obtained more precise estimates of familial risk. A MEDLINE search identified published studies that reported relative risks (RR) of PC associated with a family history of the disease. A random effects model was used to summarize study-specific RRs and 95% confidence intervals (CI). Sensitivity and sub-group analyzes were performed. Seven case-control and two cohort studies involving 6,568 PC cases were identified. There was no evidence of statistical heterogeneity between studies (I(2) = 0%; P = 0.483). Results from case-control (RR = 2.82; 95% CI: 1.99-3.66) and cohort (RR = 1.62; 95% CI: 1.28-1.97) studies showed a significant increase in PC risk associated with having an affected relative, with an overall summary RR = 1.80 (95% CI: 1.48-2.12). Similar RR were observed for early (RR = 2.69; 95% CI: 0.56-4.82) and later (RR = 3.41; 95% CI: 0.79-6.03) onset disease in the index case. Data was too sparse to generate an overall summary RR based on the number or type of affected relatives. Individuals with a family history of PC have nearly a two-fold increased risk for developing PC compared to those without such a history. Families with two or more PC cases may benefit from comprehensive risk assessment that involves collection of detailed family history information and data regarding various risk factors for PC, especially smoking history. Those at highest risk may be referred to screening programs and studies; these are important steps toward early detection and greater odds of surviving this disease.

Polymorphisms in DNA double-strand break repair genes and risk of breast cancer: two population-based studies in USA and Poland, and meta-analyses

The double-strand break DNA repair pathway has been implicated in breast carcinogenesis. We evaluated the association between 19 polymorphisms in seven genes in this pathway (XRCC2, XRCC3, BRCA2, ZNF350, BRIP1, XRCC4, LIG4) and breast cancer risk in two population-based studies in USA (3,368 cases and 2,880 controls) and Poland (1,995 cases and 2,296 controls). These data suggested weak associations with breast cancer risk for XRCC3 T241M and IVS7-14A>G (pooled odds ratio (95% confidence interval): 1.18 (1.04-1.34) and 0.85 (0.73-0.98) for homozygous variant vs wild-type genotypes, respectively), and for an uncommon variant in ZNF350 S472P (1.24 (1.05-1.48)), with no evidence for study heterogeneity. The remaining variants examined had no significant relationships to breast cancer risk. Meta-analyses of studies in Caucasian populations, including ours, provided some support for a weak association for homozygous variants for XRCC3 T241M (1.16 (1.04-1.30); total of 10,979 cases and 10,423 controls) and BRCA2 N372H (1.13 (1.10-1.28); total of 13,032 cases and 13,314 controls), and no support for XRCC2 R188H (1.06 (0.59-1.91); total of 8,394 cases and 8,404 controls). In conclusion, the genetic variants evaluated are unlikely to have a substantial overall association with breast cancer risk; however, weak associations are possible for XRCC3 (T241M and IVS7-14A>G), BRCA2 N372H, and ZNF350 S472P. Evaluation of potential underlying gene-gene interactions or associations in population subgroups will require even larger sample sizes.

Targeting the Warburg effect for cancer treatment: Ketogenic diets for management of glioma

Gliomas are a highly heterogeneous tumor, refractory to treatment and the most frequently diagnosed primary brain tumor. Although the current WHO grading system (2016) demonstrates promise towards identifying novel treatment modalities and better prediction of prognosis over time, to date, existing targeted and mono therapy approaches have failed to elicit a robust impact on disease progression and patient survival. It is possible that tumor heterogeneity as well as specifically targeted agents fail because redundant molecular pathways in the tumor make it refractory to such approaches. Additionally, the underlying metabolic pathology, which is significantly altered during neoplastic transformation and tumor progression, is unaccounted for. With several molecular and metabolic pathways implicated in the carcinogenesis of CNS tumors, including glioma, we postulate that a systemic, broad spectrum approach to produce robust targeting of relevant and multiple molecular and metabolic regulation of growth and survival pathways, critical to the modulation of hallmarks of carcinogenesis, without clinically limiting toxicity, may provide a more sustained impact on clinical outcomes compared to the modalities of treatment evaluated to date. The objective of this review is to examine the emerging hallmark of reprogramming energy metabolism of the tumor cells and the tumor microenvironment during carcinogenesis, and to provide a rationale for exploiting this hallmark and its biological capabilities as a target for secondary chemoprevention and treatment of glioma. This review will primarily focus on interventions to induce ketosis to target the glycolytic phenotype of many cancers, with specific application to secondary chemoprevention of low grade glioma- to halt the progression of lower grade tumors to more aggressive subtypes, as evidenced by reduction in validated intermediate endpoints of disease progression including clinical symptoms.

A randomized controlled trial of varying radiation doses in the treatment of choroidal melanoma

OBJECTIVE

To determine if a reduction in proton radiation dose from the standard dose of 70 cobalt gray equivalents (CGE) to 50 CGE would decrease radiation-induced complications, thereby improving visual prognosis, without compromising local tumor control for patients with uveal melanoma at high risk of these complications.

DESIGN

Randomized, double-masked clinical trial.

PARTICIPANTS

A total of 188 patients with small or medium-sized choroidal melanomas (<15 mm in diameter and <5 mm in height) near the optic disc or macula (within 4 disc diameters of either structure).

METHODS

Patients were treated with proton beam therapy at doses of either 50 CGE or 70 CGE between October 1989 and July 1994, and followed up biannually through April 1998. Outcomes included visual acuity, radiation complications, melanoma recurrence, and metastasis.

RESULTS

Proportions of patients retaining visual acuity of at least 20/200 were similar in the 2 dose groups at 5 years after radiation (approximately 55%). Similar numbers of patients in each group experienced tumor regrowth (2 patients at 50 CGE vs 3 patients at 70 CGE; P>.99) and metastasis (7 patients at 50 CGE vs 8 patients at 70 CGE;P=.79). Five-year rates of radiation maculopathy also were similar (for both groups, approximately 75% for tumors within 1 disc diameter and 40% for tumors >1 disc diameter from the macula). Rates of radiation papillopathy were nonsignificantly decreased in the 50-CGE treatment group when tumors were located 1 disc diameter or less from the optic disc (P=.20). Patients treated with the lower dose also experienced significantly less visual field loss.

CONCLUSIONS

This level of dose reduction did not result in a lesser degree of visual acuity loss. The lower-dose group did experience significantly less visual field loss. Local tumor recurrence and metastatic death rates were similar in both dose groups. Arch Ophthalmol. 2000;118:773-778

Expression of heterologous genes in Saccharomyces cerevisiae from vectors utilizing the glyceraldehyde-3-phosphate dehydrogenase gene promoter

The promoter region from the cloned glyceraldehyde-3-phosphate dehydrogenase (GPD) gene of Saccharomyces cerevisiae (Musti et al., 1983) has been characterized. A 653-bp TaqI restriction fragment with a 3' border 24 bp upstream from the ATG initiation codon was isolated and demonstrated to contain all sequences necessary for promoter function in vivo. This DNA segment was converted to a portable promoter by cloning it into M13mp9, and the entire nucleotide sequence of the portable promoter was determined. Two generalized yeast expression vectors have been constructed utilizing the GPD portable promoter. The expression vectors include the yeast 2 mu origin of replication and amplification functions, such that the plasmids are maintained at high copy number in ciro yeast hosts. These vectors direct synthesis of a consensus alpha-interferon (IFN-alpha Con1) as 1% of total cell protein. Hepatitis B surface antigen (HBsAg) was also expressed from these vectors. The 5' end of the HBsAg gene was replaced with a synthetic DNA segment which restored the deleted GPD untranslated leader and utilized optimal yeast codons for the first 30 amino acids. The partially synthetic gene resulted in a 10- to 15-fold increased expression level from GPD vectors yielding HBsAg polypeptide as 2-4% of total cell protein.

Evidence of gene-environment interactions between common breast cancer susceptibility loci and established environmental risk factors

Various common genetic susceptibility loci have been identified for breast cancer; however, it is unclear how they combine with lifestyle/environmental risk factors to influence risk. We undertook an international collaborative study to assess gene-environment interaction for risk of breast cancer. Data from 24 studies of the Breast Cancer Association Consortium were pooled. Using up to 34,793 invasive breast cancers and 41,099 controls, we examined whether the relative risks associated with 23 single nucleotide polymorphisms were modified by 10 established environmental risk factors (age at menarche, parity, breastfeeding, body mass index, height, oral contraceptive use, menopausal hormone therapy use, alcohol consumption, cigarette smoking, physical activity) in women of European ancestry. We used logistic regression models stratified by study and adjusted for age and performed likelihood ratio tests to assess gene-environment interactions. All statistical tests were two-sided. We replicated previously reported potential interactions between LSP1-rs3817198 and parity (Pinteraction = 2.4 × 10(-6)) and between CASP8-rs17468277 and alcohol consumption (Pinteraction = 3.1 × 10(-4)). Overall, the per-allele odds ratio (95% confidence interval) for LSP1-rs3817198 was 1.08 (1.01-1.16) in nulliparous women and ranged from 1.03 (0.96-1.10) in parous women with one birth to 1.26 (1.16-1.37) in women with at least four births. For CASP8-rs17468277, the per-allele OR was 0.91 (0.85-0.98) in those with an alcohol intake of <20 g/day and 1.45 (1.14-1.85) in those who drank ≥ 20 g/day. Additionally, interaction was found between 1p11.2-rs11249433 and ever being parous (Pinteraction = 5.3 × 10(-5)), with a per-allele OR of 1.14 (1.11-1.17) in parous women and 0.98 (0.92-1.05) in nulliparous women. These data provide first strong evidence that the risk of breast cancer associated with some common genetic variants may vary with environmental risk factors.

Weight change and risk of postmenopausal breast cancer (United States)

OBJECTIVE

Although many studies have shown that higher weight increases the risk of postmenopausal breast cancer, some aspects of this association are unclear. In order to examine the risk associated with different patterns of weight change, we analyzed data from a large case-control study of postmenopausal breast cancer.

METHODS

Participants included women aged 50 79 years (n = 5031) who are newly diagnosed with invasive breast cancer in Massachusetts, New Hampshire, and Wisconsin. Similarly-aged population controls (n = 5255) were selected at random from driver's license files and Medicare beneficiary lists. Height, weight, and information on other breast cancer risk factors were ascertained by structured telephone interviews from 1992 to 1995, and logistic regression was used to estimate multivariable-adjusted odds ratios (OR) and 95% confidence intervals (CI).

RESULTS

Women in the top quintile groups for height at age 20, recent weight, and recent body mass index had significantly increased risks of breast cancer. Among women who reached their highest adult weight at younger ages (<45 years), increasing weight loss since that age was associated with a reduced risk of postmenopausal breast cancer (OR 0.90, CI 0.84 0.98, per 5 kg). However, weight loss among women whose highest weight occurred after age 45 was not associated with risk (OR 1.00, CI 0.95 1.05, per 5 kg). Weight gain since the lowest adult weight increased risk by 8% for each 5 kg of gain (OR 1.08, CI 1.06-1. 11). Temporary weight cycling (weight loss followed by weight gain) was not associated with increased risk.

CONCLUSIONS

Weight gain clearly increased risk of postmenopausal breast cancer. These data lend further support to efforts aimed at helping women avoid weight gain as they age.

Prospective study of regular aspirin use and the risk of breast cancer

BACKGROUND

Evidence suggests that aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs) can inhibit tumor development in the large bowel. An inverse association between the use of NSAIDs and the incidence of breast cancer has been observed, but this association has not been statistically significant in all studies.

PURPOSE

We analyzed data from the prospective Nurses' Health Study to evaluate the influence of aspirin use on breast cancer risk.

METHODS

We studied a population of 89,528 female registered nurses who reported no history of breast or other cancers (excluding nonmelanoma skin cancer) and who returned a mailed questionnaire in 1980 that elicited information concerning breast cancer risk factors and current and past aspirin use. Follow-up questionnaires were mailed to the participants every 2 years; the women were followed through 1992. Information concerning current aspirin use was obtained from each biennial questionnaire, except in 1986. Cases of breast cancer were identified through questionnaire responses, and permission was sought for a review of medical records to confirm the diagnoses. Our analysis was based on 2414 cases of invasive breast cancer, which included 2303 cases confirmed with medical records and 111 cases for which no records were obtained. Relative risks (RRs) with 95% confidence intervals (CIs), adjusted for age or age plus other known or potential breast cancer risk factors (i.e., multivariate), were calculated.

RESULTS

Regular aspirin use (two or more tablets per week) in 1980 was unrelated to breast cancer incidence during the succeeding 12-year period (with no regular aspirin use as the referent, multivariate RR = 1.03; 95% CI = 0.95-1.12). The corresponding risk estimate for consistent regular aspirin use during the period from 1980 through 1988 was 1.01 (95% CI = 0.80-1.27). The risks were similar for heavy aspirin use (for more than two tablets per day [i.e., > 14 per week] in 1980 and in 1980 through 1988, the multivariate RRs [95% CIs] were 1.05 [0.89-1.23] and 1.09 [0.75-1.60], respectively) and for extended durations of regular use (e.g., for 20 years or more of regular use, multivariate RR = 1.00; 95% CI = 0.71-1.41).

CONCLUSION

Our results indicate that regular aspirin use does not reduce the risk of breast cancer.

Evidence-based estimates of outcome in patients irradiated for intraocular melanoma

BACKGROUND

Melanoma of the eye is the only potentially fatal ocular malignancy in adults. Until radiation therapy gained wide acceptance in the 1980s, enucleation was the standard treatment for the tumor. Long-term results after proton beam irradiation are now available.

METHODS

We developed risk score equations to estimate probabilities of the 4 principal treatment outcomes-local tumor recurrence, death from metastasis, retention of the treated eye, and vision loss-based on an analysis of 2069 patients treated with proton beam radiation for intraocular melanoma between July 10, 1975, and December 31, 1997. Median follow-up in surviving patients was 9.4 years.

RESULTS

Tumor regrowth occurred in 60 patients, and 95% of tumors (95% confidence interval, 93%-96%) were controlled locally at 15 years. Risk scores were developed for the other 3 outcomes studied. Overall, the treated eye was retained by 84% of patients (95% confidence interval, 80%-87%) at 15 years. The probabilities for vision loss (visual acuity worse than 20/200) ranged from 100% to 20% at 10 years and for death from tumor metastases from 95% to 35% at 15 years, depending on the risk group.

CONCLUSIONS

High-dose radiation treatment was highly effective in achieving local control of intraocular melanomas. In most cases, the eye was salvaged, and functional vision was retained in many patients. The mortality rate was high in an identifiable subset of patients who may benefit from adjuvant therapies directed at microscopic liver metastases.

The association between pain and disability

A clearer understanding of how pain intensity relates to disability could have important implications for pain treatment goals and definitions of treatment success. The objectives of this study were to determine the optimal pain intensity rating (0-10 scale) cutpoints for discriminating disability levels among individuals with work-related carpal tunnel syndrome (CTS) and low back (LB) injuries, whether these cutpoints differed for these conditions and for different disability measures, and whether the relationship between pain intensity and disability was linear in each injury group. Approximately 3 weeks after filing work injury claims, 2183 workers (1059 CTS; 1124 LB) who still had pain completed pain and disability measures. In the LB group, pain intensity rating categories of 1-4, 5-6, and 7-10 optimally discriminated disability levels for all four disability measures examined. In the CTS group, no pain intensity rating categorization scheme proved superior across all disability measures. For all disability measures examined, the relationship between pain intensity and disability level was linear in the CTS group, but nonlinear in the LB group. Among study participants with work-related back injuries, when pain level was 1-4, a decrease in pain of more than 1-point corresponded to clinically meaningful improvement in functioning, but when pain was rated as 5-10, a 2-point decrease was necessary for clinically meaningful improvement in functioning. The findings indicate that classifying numerical pain ratings into categories corresponding to levels of disability may be useful in establishing treatment goals, but that classification schemes must be validated separately for different pain conditions.

Genetic polymorphisms in base-excision repair pathway genes and risk of breast cancer

Impaired base-excision repair (BER) function can give rise to the accumulation of DNA damage and initiation of cancer. We evaluated whether genetic variation in six BER pathway genes (XRCC1, ADPRT, APEX1, OGG1, LIG3, and MUTYH) is associated with breast cancer risk in two large population-based case-control studies in the United States (3,368 cases and 2,880 controls) and Poland (1,995 cases and 2,296 controls). A detailed evaluation was first done in a subset of 1,898 cases and 1,514 controls with mouthwash DNA samples in the U.S. study. Significant findings were followed up in the remainder of the U.S. study population that provided cytobrush DNA samples and in the Polish study. Using data from U.S. study participants with mouthwash DNA, we found no significant overall association between breast cancer risk and XRCC1 R280H and R194W, ADPRT V726W, APEX1 D148E, OGG1 S326C, LIG3 R780H, or MUTYH 5' untranslated region. These data suggested a decreased risk for XRCC1Q399R homozygous variants compared with homozygous wild-type in premenopausal women, but these findings were not confirmed when data from cytobrush DNA samples were added [combined odds ratio (OR), 0.8; 95% confidence interval (95% CI), 0.6-1.1] or in the Polish study (OR, 1.0; 95% CI, 0.7-1.5). Meta-analyses based on our data and published data from studies of two single nucleotide polymorphisms in XRCC1 showed no evidence of an overall association between breast cancer risk and homozygous variants versus wild-type for Q399R (OR, 1.1; 95% CI, 1.0-1.2) or R194W (OR, 1.0; 95% CI, 0.7-1.8), although there was a suggestion for an association in Asian populations for Q399R (OR, 1.6; 95% CI, 1.1-2.4; P = 0.02). In conclusion, our results do not support that the polymorphisms evaluated in six BER pathway genes play a major role in breast carcinogenesis, particularly in Caucasian populations.

Worker recovery expectations and fear-avoidance predict work disability in a population-based workers' compensation back pain sample

STUDY DESIGN

Prospective, population-based cohort study.

OBJECTIVES

To examine whether worker demographic, pain, disability, and psychosocial variables, assessed soon after work-related back pain disability onset, predict 6-month work disability.

SUMMARY OF BACKGROUND DATA

Greater age, pain, and physical disability, and certain psychosocial characteristics may be risk factors for prolonged back pain-related work disability, although many studies have been small, findings have been inconsistent, and some psychosocial variables have not been examined prospectively.

METHODS

Workers (N = 1,068) completed telephone interviews assessing demographic, pain, disability, and psychosocial variables 18 days (median) after submitting Workers' Compensation back pain disability claims. Administrative measures of work disability 6 months after claim submission were obtained.

RESULTS

At 6 months, 196 workers (18.4%) were receiving work disability compensation. Age, race, education, and baseline pain and disability were significant predictors of 6-month disability. Adjusting for baseline demographics, pain, disability, and other psychosocial variables, high work fear-avoidance (odds ratio, 4.6; 95% confidence interval, 1.6-13.7) and very low recovery expectations (odds ratio, 3.1, 95% confidence interval, 1.5-6.5) were significant independent predictors.

CONCLUSIONS

Among individuals with acute work-related back pain, high pain and disability, low recovery expectations, and fears that work may increase pain or cause harm are risk factors for chronic work disability.