Coté, Michele L.

Abstract Individuals from pancreatic cancer families are at increased risk, not only of pancreatic cancer, but also of melanoma, breast, ovarian, and colon cancers. While some of the increased risk may be due to mutations in high-penetrance genes (i.e., BRCA2, PALB2, ATM, p16/CDKN2A or DNA mismatch repair genes), common genetic variants may also be involved. In a high-risk population of cases with either a family history of pancreatic cancer or early-onset pancreatic cancer (diagnosis before the age of 50 years), we examined the role of genetic variants previously associated with risk of pancreatic, breast, ovarian, or prostate cancer. We genotyped 985 cases (79 early-onset cases, 906 cases with a family history of pancreatic cancer) and 877 controls for 215,389 SNPs using the iSelect Collaborative Oncological Gene-Environment Study (iCOGS) array with custom content. Logistic regression was performed using a log-linear additive model. We replicated several previously reported pancreatic cancer susceptibility loci, including recently identified variants on 2p13.3 and 7p13 (2p13.3, rs1486134: OR = 1.36; 95% CI, 1.13–1.63; P = 9.29 × 10−4; 7p13, rs17688601: OR = 0.76; 95% CI, 0.63–0.93; P = 6.59 × 10−3). For the replicated loci, the magnitude of association observed in these high-risk patients was similar to that observed in studies of unselected patients. In addition to the established pancreatic cancer loci, we also found suggestive evidence of association (P < 5 × 10−5) to pancreatic cancer for SNPs at HDAC9 (7p21.1) and COL6A2 (21q22.3). Even in high-risk populations, common variants influence pancreatic cancer susceptibility. Cancer Epidemiol Biomarkers Prev; 25(7); 1185–91. ©2016 AACR.

Abstract Pancreatic cancer is projected to become the second leading cause of cancer-related death in the United States by 2020. A familial aggregation of pancreatic cancer has been established, but the cause of this aggregation in most families is unknown. To determine the genetic basis of susceptibility in these families, we sequenced the germline genomes of 638 patients with familial pancreatic cancer and the tumor exomes of 39 familial pancreatic adenocarcinomas. Our analyses support the role of previously identified familial pancreatic cancer susceptibility genes such as BRCA2, CDKN2A, and ATM, and identify novel candidate genes harboring rare, deleterious germline variants for further characterization. We also show how somatic point mutations that occur during hematopoiesis can affect the interpretation of genome-wide studies of hereditary traits. Our observations have important implications for the etiology of pancreatic cancer and for the identification of susceptibility genes in other common cancer types. Significance: The genetic basis of disease susceptibility in the majority of patients with familial pancreatic cancer is unknown. We whole genome sequenced 638 patients with familial pancreatic cancer and demonstrate that the genetic underpinning of inherited pancreatic cancer is highly heterogeneous. This has significant implications for the management of patients with familial pancreatic cancer. Cancer Discov; 6(2); 166–75. ©2015 AACR. This article is highlighted in the In This Issue feature, p. 109

Abstract The aim of this study was to estimate the effect of exposure to secondhand tobacco smoke on the incidence of lung adenocarcinoma in situ/minimally invasive adenocarcinoma (AIS/MIA). Data from seven case–control studies participating in the International Lung Cancer Consortium (ILCCO) were pooled, resulting in 625 cases of AIS/MIA and 7,403 controls, of whom 170 cases and 3,035 controls were never smokers. Unconditional logistic regression was used to estimate adjusted ORs (ORadj) and 95% confidence intervals (CI), controlling for age, sex, race, smoking status (ever/never), and pack-years of smoking. Study center was included in the models as a random-effects intercept term. Ever versus never exposure to secondhand tobacco smoke was positively associated with AIS/MIA incidence in all subjects (ORadj = 1.48; 95% CI, 1.14–1.93) and in never smokers (ORadj = 1.45; 95% CI, 1.00–2.12). There was, however, appreciable heterogeneity of ORadj across studies (P = 0.01), and the pooled estimates were largely influenced by one large study (40% of all cases and 30% of all controls). These findings provide weak evidence for an effect of secondhand tobacco smoke exposure on AIS/MIA incidence. Further studies are needed to assess the impact of secondhand tobacco smoke exposure using the newly recommended classification of subtypes of lung adenocarcinoma. Cancer Epidemiol Biomarkers Prev; 24(12); 1902–6. ©2015 AACR.

Abstract Although the association between benign breast disease (BBD) and risk of subsequent breast cancer is well-established, no previous studies have compared characteristics of breast cancers in women with a history of BBD to characteristics of cancers in the general population. In this study, we compared the characteristics of 109 breast cancers that developed in a population of African-American women with a history of benign breast disease (BBD population) to 10,601 breast cancers that developed in a general population of African-American women whose cancers were recorded by the Metropolitan Detroit Cancer Surveillance System (MDCSS population). The populations were compared on demographic characteristics such as age, marital status, and previous cancers, as well as clinical characteristics such as tumor hormone receptor status, grade, stage, behavior, size, and treatment. Overall and breast cancer-specific survival were also compared between populations. Women in the BBD population developed lower grade, earlier stage cancers that were more likely to be hormone receptor-positive and less likely to exhibit invasive behavior. Women in the BBD population were also significantly less likely to die from breast cancer after ten years of follow-up. These results suggest that although women with a history of BBD are at greater breast cancer risk, their breast cancers may be more likely to be detected early, leading to better breast cancer-specific survival. Citation Format: Susanna D. Mitro, Rouba Ali-Fehmi, Sudeshna Bandyopadhyay, Baraa Alosh, Bassam Albashiti, Quratulain Ahmed, Derek C. Radisky, Marlene H. Frost, Amy C. Degnim, Julie J. Ruterbusch, Michele L. Cote. Clinical characteristics of breast cancers in African American women with benign breast disease: A comparison to the Surveillance, Epidemiology and End Results Program. [abstract]. In: Proceedings of the Sixth AACR Conference: The Science of Cancer Health Disparities; Dec 6–9, 2013; Atlanta, GA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2014;23(11 Suppl):Abstract nr B39. doi:10.1158/1538-7755.DISP13-B39

Abstract Background: Statins are the most widely prescribed cholesterol-lowering drugs in the United States, with approximately 25% of US adults using statins by 2008. The anti-carcinogenic effect of statins may reduce the metastatic potential of cancer cells leading to ‘stage migration’ with statin users more likely diagnosed with early rather than late stage cancer. We evaluated the effects of statins on breast cancer stage migration and breast cancer-specific mortality in the Women’s Health Initiative (WHI) Clinical Trial and Observational Study. Methods: The study population included 128,675 postmenopausal women aged 50 to 79 years, with 7,883 newly-diagnosed pathologically-confirmed cases of in situ (19%), local stage (61%), regional stage (19%) and distant stage (1%) breast cancer and 401 deaths due to breast cancer after an average of 11.5 (SD=3.7) years of follow-up. To reduce the possibility of detection bias, we excluded women who did not report a mammogram within 5 years of study entry, and who had no health insurance or medical care provider (n=28,237). Stage was coded using criteria implemented in the Surveillance, Epidemiology and End Results Program and stratified into early stage (in situ and local) vs. late stage (regional and distant). Information on statin use prior to breast cancer diagnosis was collected at baseline and years one, three, six, and nine years post-baseline. Self- and interviewer-administered questionnaires were used to collect risk factor information. Cause of death was based on medical record review by physician adjudicators. Cox proportional hazards regression models were used to calculate hazard ratios (HR) with 95% confidence intervals (CI) to evaluate the relationship between statin use as a time-dependent exposure and diagnosis of late stage breast cancer and breast cancer-specific mortality adjusting for important confounders. For these models, participants who had early stage breast cancer or who died during follow-up were censored at time of diagnosis or death, respectively. We also evaluated the effect of statins stratified by estrogen receptor (ER) status. Statistical tests were two-sided. Results: Statins were used by 10,474 women (8%) at baseline. In the multivariable-adjusted time-dependent model, statin use was associated with a marginal reduction in risk of late stage breast cancer (HR 0.84, 95% CI: 0.70-1.02, p=0.082) and a reduction in risk of late stage estrogen receptor positive breast cancer (HR 0.79, 95% CI: 0.63-0.99, p=0.044). Statin use was also associated with a marginal reduction in breast cancer-specific mortality although it did not reach statistical significance (HR 0.59, 95% CI: 0.32-1.06, p=0.075). Conclusions: In the WHI, statin use was associated with a modest reduction in risk of late stage estrogen positive breast cancer and a non-significant decrease in breast cancer mortality. We are currently performing sensitivity analyses on these models. Studies using other large data sets with longer follow-up and information on cancer-directed therapy are needed to further evaluate this possible association. Citation Format: Monica P Arun, Pinkal Desai, Amy Lehman, Marilyn L Kwan, JoAnn E Manson, Sayeh Lavasani, Sylvia Wasswertheil-Smoller, Gloria E Sarto, Meryl S LeBoff, Jane Cauley, Michele L Cote, Jennifer Beebe-Dimmer, Allison Jay, Rowan T Chlebowski, Michael S Simon. Statins and breast cancer stage and mortality in the Women's Health Initiative cohort [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr P6-10-04.

Abstract Benign breast disease (BBD) is an established risk factor for breast cancer among Caucasian women but less is known about BBD in African American women. As African American women suffer from disproportionate mortality due to breast cancer, special focus on pathologic characteristics that may influence disease risk is warranted. Benign breast biopsies from African American women were identified by the University Pathology Group (Detroit, MI). African American women of ages 20 to 84 years, who underwent a breast biopsy from 1997 to 2000, were eligible for the study. Subsequent breast cancers were identified through a linkage with the Detroit Surveillance Epidemiology and End Results (SEER) program. The first biopsy was reviewed by the pathologist, and lesions were classified following Dupont and Page criteria along with involution and other histologic features. Logistic regression was used to estimate the risk of developing a subsequent breast cancer with the histologic characteristics of BBD. A total of 1,406 BBD biopsies from African American women were included in this study with a median follow-up of 10.1 years. The majority (68%) showed nonproliferative disease, 29% had proliferative disease without atypia, and 3% had proliferative disease with atypia. Subsequent incident breast cancers occurred in 55 women (3.9%). Women whose biopsies showed proliferative disease with atypia were more than three-fold more likely to develop breast cancer as compared with women who had nonproliferative disease [relative risk (RR) 3.29, 95% confidence interval (CI) 1.21–8.93]. Better characterization of the risk of breast cancer among women with BBD, considering both ethnicity and detailed molecular findings, can lead to better surveillance, earlier diagnosis, and potentially improved survival. Cancer Prev Res; 5(12); 1375–80. ©2012 AACR.

Abstract Pancreatic ductal adenocarcinoma (PDA) affects over 44,000 people in the United States every year and carries a dismal prognosis, with a 5-year survival rate of just 5%. A subset of these patients (5-10%) report a familial history of the disease. The genetic etiology in these familial cases is poorly defined, with known susceptibility genes, such as: BRCA2, PALB2, CDKN2A, BRCA1, PRSS1 and STK11, accounting for only 10-15% of familial pancreatic cancer. In an effort to identify previously unappreciated pancreatic cancer susceptibility genes, we used next generation sequencing technology to evaluate the whole genome and whole exome sequences of 16 (6 families) and 22 individuals (10 families) respectively. All of these families enrolled into one of the familial pancreatic cancer registries participating in the Pancreatic Cancer Genetic Epidemiology (PacGene) Consortium, all had at least three members with PDA, and DNA was available from at least two affected members in each kindred. Using this approach, we identified heterozygous, inactivating, ATM mutations in two kindreds with familial pancreatic cancer (c.8266A>AT; p.K2756X and c.170G>GA; p.W57X). These mutations were previously reported as disease causing variants in patients with ataxia-telangiectasia, an autosomal recessive condition resulting from bi-allelic deleterious mutations of ATM. Interestingly, heterozygotes of deleterious ATM mutations have an increased risk of breast cancer. However, there have been no previous reports of deleterious ATM mutations in the germline of familial PDA patients. In our study, mutations segregated with disease in both kindreds and tumor analysis demonstrated Loss of heterozygosity (LOH) of the wild-type allele. Sequence analysis of the entire ATM gene in an additional 166 familial pancreatic cancer probands indentified four additional patients with deleterious mutations in the ATM gene (c.3214G>GT; p.E1072X, c.6095G>GA; p.R2032K, IVS41-1G>GT and c.3801delG), while no deleterious mutations were identified in 190 spouse controls (p=0.046). When considering only the mostly severely affected families, those with three or more pancreatic cancer cases, four deleterious mutations were found in 87 families (P=0.009). These results indicate that ATM mutations play an important role in familial pancreatic cancer predisposition and have significant implications in the management of affected individuals and the risk assessment of family members. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 2628. doi:1538-7445.AM2012-2628

Abstract African American (AA) women have higher mortality rates from breast cancer (BrCa) and are diagnosed at younger ages than their Caucasian counterparts. Women who have had a benign breast biopsy are at increased risk of the disease, although less is known about the risk of BrCa associated with benign breast disease in AA women. We examined 1428 breast biopsies from AA women which occurred from 1997–2000 and assessed various pathologic markers including: apocrine metaplasia, ductal hyperplasia including atypia, evidence of cysts, duct ectasia, fibrosis, intra-ductal papilloma, sclerosing adenosis, columnar alteration, and involution (atrophy). These women were followed for later BrCa through the Metropolitan Detroit Cancer Surveillance System, part of the Surveillance, Epidemiology and End Results (SEER) program through 2008. Women who developed BrCa were compared to those in the cohort who did not, and to other AA women with BrCa in the SEER registry. AA women in our study were also compared to Caucasian women in the Mayo Clinic cohort. Differences in variables were assessed by chi-squared tests and 95% confidence intervals. Of the 1428 biopsies, 52 (3.6%) subsequent incident breast cancers were reported in SEER. The mean age at diagnosis was 59, and the mean time from biopsy to BrCa diagnosis was 6.1 years. Individuals with atypical ductal hyperplasia at biopsy (n=37, 2.6%) were more likely to develop breast cancer (n=7, 13.5%, p<0.01). No other pathologic variables were associated with increased risk. Women in our cohort with breast cancer did not differ from AA in the SEER database with respect to age at diagnosis, stage at diagnosis, or receptor positivity. Compared to the Caucasian women in the Mayo Clinic BBD cohort, AA women in our study were younger at biopsy (p<0.01), but had similar percentages of involution and atypia (p=0.50 and 0.15, respectively). Our preliminary findings among a relatively small group of AA women with prior benign breast biopsies and incident breast cancers suggest that results from the Mayo Cohort study are likely to apply to AA populations. Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P1-08-16.