Citations

Abstract B39 Background The breast glandular epithelium is composed of lobules that undergo age-related involution that increases as women age and has been associated with lowered breast cancer risk. Mammographic density (MD) is an established risk factor for breast cancer that has been shown to decrease with age. This study examined the association of age-related lobular involution with mammographic breast density. Materials and Methods The study sample was selected from approximately 20,000 healthy women who were enrolled in a screening cohort at the Mayo Clinic (Mayo Mammography Health Study) from 2003 to 2006 and had a benign breast biopsy (BBD) within 2 years of the enrollment mammogram. A quantitative measure of mammographic density, percent density (PD) was estimated on the enrollment mammogram, in addition to its components dense and nondense area (NDA). All biopsies were reviewed by a breast pathologist for the type of benign breast disease (BBD) as well as lobular involution status. Involution was defined as the proportion of terminal ductal lobular units (TDLUs) in the background tissue on biopsy that showed at least 50% decrease in size and number of acini from normal lobules and was subjectively assessed as: No- 0% involution, Partial- 1 to 74%, or Complete- >75% involution. Mean density was estimated for the 3 categories of involution using generalized linear models and square root transformation. Confounders were assessed including age, parity, body mass index (BMI), type of BBD, menopausal status, age at first birth and family history Results A total of 317 women from the MMHS had BBD within 2 years of enrollment. Mean age at BBD diagnosis in this sample was 55 years. Age- and BMI- adjusted analyses suggested an inverse association of involution and percent density with adjusted mean PD values of 23.3 (95%CI [17.2, 30.3]) for no involution, 21.9 (95%CI [20.0, 23.9]) for partial involution, and 17.8 (95% CI [14.7, 21.3]) for complete involution (p for trend 0.05). This trend was driven primarily by the positive association of involution with nondense area with adjusted mean NDA values of 103.1cm2 (95% CI [86.1, 121.7]) for no involution, 104.9 cm2 (95% CI [99.4, 110.7]) for partial involution, and 126.2 cm2 (95% CI [115.0, 137.9]) for complete involution (p for trend 0.004). Discussion Our findings suggest that MD is inversely associated with involution of breast tissues, providing a plausible mechanism through which MD influences breast cancer risk. Citation Information: Cancer Prev Res 2008;1(7 Suppl):B39.

Abstract Background: Colorectal cancer (CRC) is the third most common incident cancer among women in the United States. Alcohol use has been proposed as a CRC risk factor, but existing observational data remain inconsistent. To date, relatively few studies have examined associations between alcohol use and CRC risk based on molecularly-defined subtypes. Aim: To evaluate associations between alcohol use and incident CRC overall, as well as by molecularly-defined subtypes including microsatellite instability (MSI), CpG island methylator phenotype (CIMP) and BRAF mutation status in the prospective, population-based, Iowa Women's Health Study (IWHS). Methods: The IWHS recruited 41,836 randomly selected Iowa women, ages 55–69 years at enrollment, in 1986. Women with prevalent cancers or no follow-up were excluded, leaving 38,001 eligible for this study. Alcohol use was obtained from a self-administered food frequency questionnaire at study baseline. Incident CRCs were identified through annual linkage with the State Health Registry of Iowa. Archived, paraffin-embedded tissue specimens were recently requested for incident CRC cases diagnosed through December 31, 2002. In the present study, useable tissue specimens were obtained and molecularly characterized for 563/1,255 cases (45%), whose baseline age, body mass index, physical activity level, total energy intake and alcohol use were similar to non-retrieved cases (p > 0.05 for each comparison). Alcohol use was categorized as never (n=21,464), < 3.4 g/day (n=8,313) and > 3.4 g/day (n=8,224), based on the median split among users. Molecularly-defined CRC subtypes were categorized as MSI-high (MSIH; n=148), MSI-low or microsatellite stable (MSI-L/MSS; n=400); CIMP-positive (n=167) or CIMP-negative (n=368); and BRAF-mutation (n=154) or BRAF-wildtype (n=391). Relative risks (RRs) and 95% confidence intervals (95% CIs) were estimated for alcohol use compared to never drinkers, using multivariable Cox regression models adjusted for body mass index, waist-to-hip ratio, smoking status, physical activity level, exogenous estrogen use, and daily intakes of total energy, total fat, red meat, sucrose, calcium, folate, methionine and vitamin E. Results: There was no statistically significant association between alcohol use and overall CRC risk (RR=1.00; 95% CI = 0.86–1.15 for < 3.4 g/day versus none; RR=1.06; 95% CI=0.91–1.24 for >3.4 g/day versus none). Further, there were no associations with alcohol use for specific, molecularly-defined CRC subtypes (RRs shown for > 3.4 g/day versus none): MSI-H (RR=1.07; 95% CI=0.70–1.64); MSI-L or MSS (RR=1.12; 95% CI=0.85–1.47); CIMP-positive (RR=0.97; 95% CI=0.64–1.47); CIMP-negative (RR=1.13; 95% CI=0.85–1.50); BRAF-mutation (RR=0.94; 95% CI=0.61–1.45); and BRAF-wildtype (RR=1.20; 95% CI=0.91–1.57). Conclusion: In this cohort of older women, alcohol use did not appear to be a risk factor for incident CRC, overall or by the defined molecular subtypes. Citation Information: Cancer Prev Res 2010;3(1 Suppl):A115.

Abstract Background: Postmenopausal hormone (PMH) therapy represents a controversial colorectal cancer (CRC) preventive intervention. Because colorectal carcinogenesis is a heterogeneous process, we evaluated associations between PMH therapy and incident CRC in relation to KRAS mutation status in a population-based cohort of older women [Iowa Women's Health Study (IWHS)]. Methods: The IWHS enrolled 41,836 randomly selected women, ages 55 to 69 years, in 1986. PMH therapy and other exposure data were recorded at baseline. Tissue samples from prospectively identified CRC cases (n = 507) were analyzed for somatic KRAS mutations (exon 2, codons 12 and 13). Multivariable Cox regression models were fit to estimate relative risks (RR) and 95% confidence intervals (CI). Results: PMH therapy (ever vs. never) was inversely associated with KRAS mutation–negative (RR = 0.83; 95% CI, 0.66–1.06; P = 0.14) and KRAS mutation–positive (RR = 0.82; 95% CI, 0.58–1.16; P = 0.27) tumors, although the observed risk estimates were not statistically significant. When anatomic subsite was additionally considered, the strongest association was found for KRAS mutation–negative, distal colorectal tumors (RR = 0.64; 95% CI, 0.43–0.96; P = 0.03). Conclusions: To our knowledge, we provide the first report of KRAS-defined CRC risks associated with PMH therapy. These data suggest that PMH therapy may reduce CRC risk through mechanisms beyond KRAS mutation status but might provide greater benefits for KRAS mutation–negative than mutation-positive tumors (at least in the distal colorectum). Impact: Findings from this prospective cohort study provide novel insights about the molecular biology of PMH therapy–related CRC risk reduction. Cancer Epidemiol Biomarkers Prev; 21(4); 681–4. ©2012 AACR.

Background— Little is known about what treatments patients receive after being diagnosed with stable coronary artery disease or what the comparative outcomes are for routine medical treatment (RMT) versus percutaneous coronary intervention (PCI) with RMT for patients in a setting apart from randomized controlled trials. Methods and Results— Patients with stable coronary artery disease undergoing cardiac catheterization in New York State between 2003 and 2008 were followed up to determine the treatment they received. Patients receiving RMT and patients receiving PCI with RMT were propensity matched through the use of 20 factors that could have a bearing on outcomes. The resulting cohort of 933 matched pairs was used to compare mortality/myocardial infarction (MI), mortality, MI, and subsequent revascularization rates. A total of 89% of all patients underwent PCI with RMT. PCI/RMT patients had significantly lower adverse outcome rates at 4 years for mortality/MI (16.5% versus 21.2%; P =0.003), mortality (10.2% versus 14.5%; P =0.02), MI (8.0% versus 11.3%; P =0.007), and subsequent revascularization (24.1% versus 29.1%; P =0.005). Adjusted RMT versus (PCI with RMT) hazard ratios were 1.49 (95% confidence interval, 1.16–1.93) for mortality/MI and 1.46 (95% confidence interval, 1.08–1.97) for mortality. There were no differences for patients ≤65 years of age or for patients with single-vessel disease. Conclusions— Most patients with stable coronary artery disease in New York undergoing catheterization between 2003 and 2008 received PCI. Patients who received PCI experienced lower mortality, mortality/MI, and revascularization rates. The reasons for this finding need to be better understood, including the possible role of low medication adherence rates that have been found in other studies.

Background Postmenopausal hormone (PMH) therapy may reduce colorectal cancer (CRC) risk, but existing data are inconclusive. Objectives To evaluate associations between PMH therapy and incident CRC, overall and by molecularly defined subtypes, in the population-based Iowa Women's Health Study of older women. Methods Exposure data were collected from Iowa Women's Health Study participants (55–69 years) at baseline (1986). Archived, paraffin-embedded tissue specimens for 553 CRC cases were collected and analysed to determine microsatellite instability (MSI-L/MSS or MSI-H), CpG island methylator phenotype (CIMP-negative or CIMP-positive) and BRAF mutation ( BRAF -wildtype or BRAF -mutated) status. Multivariable Cox regression models were fit to estimate RRs and 95% CIs. Results PMH therapy (ever vs never use) was inversely associated with incident CRC overall (RR=0.82; 95% CI 0.72 to 0.93), with a significantly lower risk for MSI-L/MSS tumours (RR=0.75; 95% CI 0.60 to 0.94), and borderline significantly lower risks for CIMP-negative (RR=0.79; 95% CI 0.63 to 1.01) and BRAF -wildtype (RR=0.83; 95% CI 0.66 to 1.04) tumours. For PMH therapy >5 years, the subtype-specific risk estimates for MSI-L/MSS, CIMP-negative and BRAF -wildtype tumours were: RR=0.60, 95% CI 0.40 to 0.91; RR=0.68, 95% CI 0.45 to 1.03; and RR=0.70, 95% CI 0.47 to 1.05, respectively. PMH therapy was not significantly associated with the MSI-H, CIMP-positive or BRAF -mutated CRC subtypes. Conclusions In this prospective cohort study, PMH therapy was inversely associated with distinct molecularly defined CRC subtypes, which may be related to differential effects from oestrogen and/or progestin on heterogeneous pathways of colorectal carcinogenesis.

Background— The impact of incomplete revascularization (IR) on adverse outcomes after percutaneous coronary intervention remains inconclusive, and few studies have examined mortality during follow-ups longer than 5 years. The objective of this study is to test the hypothesis that IR is associated with higher risk of long-term (8-year) mortality after stenting for multivessel coronary disease. Methods and Results— A total of 13 016 patients with multivessel disease who had undergone stenting procedures with bare metal stents in 1999 to 2000 were identified in the New York State's Percutaneous Coronary Intervention Reporting System. A logistic regression model was fit to predict the probability of achieving complete revascularization (CR) in these patients using baseline risk factors; then, the CR patients were matched to the IR patients with similar likelihoods of achieving CR. Each patient's vital status was followed through 2007 using the National Death Index, and the difference in long-term mortality between IR and CR was compared. It was found that CR was achieved in 29.2% (3803) of the patients. For the 3803 pair-matched patients, the respective 8-year survival rates were 80.8% and 78.5% for CR and IR ( P =0.04), respectively. The risk of death was marginally significantly higher for IR (hazard ratio=1.12; 95% confidence interval, 1.01–1.26, P =0.04). The 95% bootstrap confidence interval for the hazard ratio was 0.98 to 1.32. Conclusions— IR may be associated with higher risk of long-term mortality after stenting with BMS in patients with multivessel disease. More prospective studies are needed to further test this association.