Sherman, Mark E.

Abstract Little is known about the effects of many recognized breast cancer risk factors on the normal breast. We hypothesize that risk factors affect the number and morphometry of terminal ductal lobular units (TDLUs), the microanatomical structure from which most breast cancers arise. To assess this hypothesis, we evaluated relationships between breast cancer risk factors and TDLU number, TDLU diameter, and acini per TDLU in breast tissue donated by healthy volunteers. Subjects included 786 healthy women ages 18-84 years without a personal history of any cancer, who provided a risk factor questionnaire and donated a 10-guage needle core from the upper outer breast quadrant. A pathologist, masked to subject data, assessed TDLU number per section, TDLU diameter and acini per TDLU using digitized images of hematoxylin and eosin stained sections of tissue. Seventy-two randomly selected images were examined by two additional pathologists. We generated ordered categorical variables for the number of TDLUs per section (0-1, 2-8, 9+), median TDLU diameter (53-262, 263-377, 378-1375 microns) and median number of acini per TDLU (2-10, 11-20, 21+). We computed Spearman correlations between measures, and intraobserver and interobserver agreement. Associations between breast cancer risk factors and TDLU measures were assessed by estimating odds ratios (OR) and 95% confidence intervals (CI) using ordinal logistic regression models, adjusted for age. TDLU diameter and acini count were highly correlated (rho =0.71); TDLU number per section was less strongly related to the diameter (rho= 0.18) and acini measures (rho=0.20). Inter and intraobserver agreement for TDLU measures were highly correlated (rho range 0.68-0.98). All TDLU measurements were significantly lower among women age 50 years and older compared with younger women. Compared with Caucasians, African American women had more TDLUs per section (ORadj=2.03, 95% CI= 1.06-3.89). Greater numbers of TDLUs were also related to having a family history of two or more relatives with breast cancer compared with none (ORadj=2.01, 95% CI=0.91-4.46); and for parous compared with nulliparous women (ORadj=1.61, 95% CI=1.16-2.25). In contrast, parity was associated with reduced median number of acini per TDLU (ORadj=0.60, 95% CI = 0.40-0.90) and median diameter (ORadj=0.64, 95% CI = 0.42-0.96) compared with nulliparity. Our data suggest that TDLUs are more frequent among women with a positive family history of breast cancer or African Americans. Parity, an established protective factor for breast cancer risk, was related to increased numbers of TDLUs, but fewer acini per TDLU, suggesting that TDLUs may increase with pregnancy and then involute. Our data, along with published results linking TDLU involution with a reduction in breast cancer risk, suggest TDLU morphometry may reflect early biologic changes marking breast cancer susceptibility. 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 4465. doi:1538-7445.AM2012-4465

Abstract Epidemiologic studies suggest that breast cancer risk factor associations vary by tumor marker expression; however, individual studies have had limited power to address this question. We pooled data from up to 35,568 invasive breast cancer cases from 34 studies participating in the Breast Cancer Association Consortium (BCAC) to evaluate associations between established risk factors (age at menarche, nulliparity, age at first full time birth [AFFTB], body mass index [BMI] and family history) and breast cancer subtypes, defined by immunohistochemical expression of ER, PR, HER2, and basal markers (CK5/6 or CK5, EGFR). We used polychotomous logistic regression to evaluate relationships between risk factors and tumor subtypes in case-only analyses and to estimate case-control odds ratios and 95% confidence intervals for the associations between risk factors and specific tumor subtypes in 11 population-based studies including up to 12,841 cases and 17,032 controls. In case-only analyses, we found that reproductive risk factors were more common in hormone receptor positive tumors: early age at menarche was most strongly related to PR status (34.6% vs. 32.4% of women with age at menarche ≤12 years among PR+ and PR- cases, respectively, P= 0.001); whereas nulliparity, and late AFFTB in parous women were most strongly related to ER status (15.3% vs. 13.6% nulliparous women, 17.1% vs. 15.2% women with late AFFTB [≥30 years], among ER+ and ER- cases, respectively, P=2.6×10−6 for nulliparity and P=2.0×10−7 for late AFFTB). Nulliparity and late AFFTB were less common among triple negative (TN) tumors overall and among TN tumors expressing basal markers. Elevated BMI in women aged 50 years or younger was more common in ER-&PR- than ER+&PR+ tumors (17.0% vs 13.6% women with BMI ≥30, respectively, P=1.3×10−7), whereas above age 50 years, elevated BMI was more common in ER+&PR+ than ER+&PR- tumors (20.9% vs 16.7% women with BMI ≥30, respectively, P=2.8×10−8 comparing BMI ≥30 to BMI <25). In case-control analyses, early age at menarche was associated with increased risk of PR+ tumors; nulliparity and late AFFTB were most strongly associated with increased risk of (ER+ or PR+)&HER2- tumors, and did not increase the risk of TN tumors. Having a family history of breast cancer increased the risk of all tumor subtypes, although the association was strongest for TN tumors expressing basal markers. Our data provide convincing evidence for etiological heterogeneity with respect to breast cancer risk factors stratified by ER and PR status. Stratification by additional markers provides additional insights about etiologic differences in breast cancer risk. Note: This abstract was not presented at the AACR 101st Annual Meeting 2010 because the presenter was unable to attend. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 870.

Abstract The p53 protein is critical for multiple cellular functions including cell growth and DNA repair. We assessed whether polymorphisms in the region encoding TP53 were associated with risk of invasive ovarian cancer. The study population includes a total of 5,206 invasive ovarian cancer cases (2,829 of which were serous) and 8,790 controls from 13 case-control or nested case-control studies participating in the Ovarian Cancer Association Consortium (OCAC). Three of the studies performed independent discovery investigations involving genotyping of up to 23 single nucleotide polymorphisms (SNP) in the TP53 region. Significant findings from this discovery phase were followed up for replication in the other OCAC studies. Mixed effects logistic regression was used to generate posterior median per allele odds ratios (OR), 95% probability intervals (PI), and Bayes factors (BF) for genotype associations. Five SNPs showed significant associations with risk in one or more of the discovery investigations and were followed up by OCAC. Mixed effects analysis confirmed associations with serous invasive cancers for two correlated (r2 = 0.62) SNPs: rs2287498 (median per allele OR, 1.30; 95% PI, 1.07–1.57) and rs12951053 (median per allele OR, 1.19; 95% PI, 1.01–1.38). Analyses of other histologic subtypes suggested similar associations with endometrioid but not with mucinous or clear cell cancers. This large study provides statistical evidence for a small increase in risk of ovarian cancer associated with common variants in the TP53 region. [Cancer Res 2009;69(6):2349–57]