Pankratz, V. Shane

Purpose Accurate breast cancer risk assessment is vital to personalize screening and risk reduction strategies. Women with atypical hyperplasia have a four-fold higher risk of breast cancer. We evaluated the performance of the Tyrer-Cuzick model, which was designed to predict 10-year risk of breast cancer development, in a well-defined cohort of women with atypia. Patients and Methods The Mayo Benign Breast Disease cohort includes 9,376 women who had a benign breast biopsy between 1967 and 1991. Among those, 331 women with atypia were identified by our study pathologists. Risk factor data for the Tyrer-Cuzick model were collated for each woman and used to predict individual risk of developing invasive breast cancer within 10 years. Results Over a median follow-up of 14.6 years, 64 (19%) of the 331 women developed invasive breast cancer. In the first 10 years after biopsy, 31 women developed invasive breast cancer whereas the Tyrer-Cuzick model predicted 58.9. The observed-to-predicted ratio was 0.53 (95% CI, 0.37 to 0.75). The concordance statistic was 0.540, revealing that the Tyrer-Cuzick model did not accurately distinguish, on an individual level, between women who developed invasive breast cancer and those who did not. Conclusion The Tyrer-Cuzick model significantly overestimated risk of breast cancer for women with atypia, and individual risk estimates showed poor concordance between predicted risk and invasive breast cancer development. Thus, we cannot recommend the use of the Tyrer-Cuzick model to predict 10-year breast cancer risk in women with atypical hyperplasia.

Purpose Mammographic density and lobular involution are both significant risk factors for breast cancer, but whether these reflect the same biology is unknown. We examined the involution and density association in a large benign breast disease (BBD) cohort. Patients and Methods Women in the Mayo Clinic BBD cohort who had a mammogram within 6 months of BBD diagnosis were eligible. The proportion of normal lobules that were involuted was categorized by an expert pathologist as no (0%), partial (1% to 74%), or complete involution (≥ 75%). Mammographic density was estimated as the four-category parenchymal pattern. Statistical analyses adjusted for potential confounders and evaluated modification by parity and age. We corroborated findings in a sample of women with BBD from the Mayo Mammography Health Study (MMHS) with quantitative percent density (PD) and absolute dense and nondense area estimates. Results Women in the Mayo BBD cohort (n = 2,667) with no (odds ratio, 1.7; 95% CI, 1.2 to 2.3) or partial (odds ratio, 1.3; 95% CI, 1.0 to 1.6) involution had greater odds of high density (DY pattern) than those with complete involution (P trend < .01). There was no evidence for effect modification by age or parity. Among 317 women with BBD in the MMHS study, there was an inverse association between involution and PD (mean PD, 22.4%, 21.6%, 17.2%, for no, partial, and complete, respectively; P trend = .04) and a strong positive association of involution with nondense area (P trend < .01). No association was seen between involution and dense area (P trend = .56). Conclusion We present evidence of an inverse association between involution and mammographic density.

Purpose Accurate, individualized risk prediction for breast cancer is lacking. Tissue-based features may help to stratify women into different risk levels. Breast lobules are the anatomic sites of origin of breast cancer. As women age, these lobular structures should regress, which results in reduced breast cancer risk. However, this does not occur in all women. Methods We have quantified the extent of lobule regression on a benign breast biopsy in 85 patients who developed breast cancer and 142 age-matched controls from the Mayo Benign Breast Disease Cohort, by determining number of acini per lobule and lobular area. We also calculated Gail model 5-year predicted risks for these women. Results There is a step-wise increase in breast cancer risk with increasing numbers of acini per lobule (P = .0004). Adjusting for Gail model score, parity, histology, and family history did not attenuate this association. Lobular area was similarly associated with risk. The Gail model estimates were associated with risk of breast cancer (P = .03). We examined the individual accuracy of these measures using the concordance (c) statistic. The Gail model c statistic was 0.60 (95% CI, 0.50 to 0.70); the acinar count c statistic was 0.65 (95% CI, 0.54 to 0.75). Combining acinar count and lobular area, the c statistic was 0.68 (95% CI, 0.58 to 0.78). Adding the Gail model to these measures did not improve the c statistic. Conclusion Novel, tissue-based features that reflect the status of a woman's normal breast lobules are associated with breast cancer risk. These features may offer a novel strategy for risk prediction.

Background Inflammation is proposed to play a role in the development of Alzheimer's disease, and may also be involved in the pathogenesis of mild cognitive impairment (MCI). This study examined the association of inflammatory markers in serum or plasma with prevalent MCI and MCI subtypes in a population‐based sample. Methods Olmsted County, MN, residents aged 70–89 years on October 1, 2004, were evaluated using the Clinical Dementia Rating Scale, a neurological evaluation, and neuropsychological testing. Information ascertained for each participant was reviewed by an expert panel of neuropsychologists, physicians, and nurses, and a diagnosis of normal cognition, MCI, or dementia was made by consensus. C‐reactive protein (CRP), interleukin‐6 (IL‐6), tumor necrosis alpha (TNFα), and adiponectin were measured at baseline. Results Among 313 subjects with MCI and 1570 cognitively normal subjects, a CRP level in the upper quartile (>3.3 mg/L) was significantly associated with MCI (odds ratio [OR], 1.42; 95% confidence interval [CI], 1.00–2.01) and with nonamnestic MCI (OR, 2.05; 95% CI, 1.12–3.78) after adjusting for age, sex, and years of education. However, there was no association with amnestic MCI (OR, 1.21; 95% CI, 0.81–1.82). No association was observed with the other inflammatory markers. Conclusions Plasma CRP is associated with prevalent MCI and with nonamnestic MCI in elderly, nondemented persons in a population‐based setting. These findings suggest the involvement of inflammation in the pathogenesis of MCI.

Abstract Microcephalin (MCPH1) is a BRCA1 COOH terminal (BRCT) domain containing protein involved in the cellular response to DNA damage that has been implicated in autosomal recessive primary microcephaly. MCPH1 is recruited to sites of DNA double-strand breaks by phosphorylated histone H2AX (γH2AX), but the mechanism by which MCPH1 contributes to the repair process remains to be determined. Here, we show that MCPH1 binds to BRCA2 and regulates the localization of BRCA2 and Rad51 at sites of DNA damage. The interaction occurs through the NH2 terminus of BRCA2 and the COOH terminal BRCT domains of MCPH1. Disruption of the interaction between MCPH1 and BRCA2 has no effect on the ability of BRCA2 to form a complex with Rad51 but is associated with substantially reduced levels of both BRCA2 and Rad51 at sites of DNA double-strand breaks. Uncoupling of MCPH1 from BRCA2 also interferes with Rad51-dependent and BRCA2-dependent homologous recombination repair activity. These results suggest that the role of MCPH1 in the DNA damage response is in part associated with the ability to localize BRCA2 to sites of DNA double-stand breaks. [Cancer Res 2009;69(13):5531–6]