Abstract A20: Random periareolar fine-needle aspiration is highly reproducible in a CALGB multi-institutional cross-sectional study

Abstract

Abstract Background: Biomarkers that vary with risk and response to prevention interventions are referred to as “surrogate endpoint biomarkers”. As outlined by Fabian et al., surrogate endpoint biomarkers should be 1) biologically and statistically significantly associated with cancer development, 2) present in a reasonable proportion of at-risk individuals, 3) obtainable by minimally invasive procedures, and 4) reversible with prevention interventions that have been validated to decrease cancer incidence. Many modalities have been suggested as potential surrogate endpoint biomarkers for breast cancer, including mammographic density, serum biomarkers, and breast tissue biomarkers. Currently, there is no consensus as to the optimal surrogate endpoint biomarker. Random Periareolar Fine Needle Aspiration (RPFNA) is a research technique developed to assess short-term breast cancer risk in women at increased risk for breast cancer. While there is increasing acceptance of RPFNA, neither the reproducibility nor the inter-institutional compatibility of RPFNA has been established. To address these key limitations, the Cancer and Leukemia Group B (CALGB) Prevention Group tested the reproducibility of RPFNA in a multi-institutional cross-sectional study. Methods: Sixty-three high-risk women from five CALGB institutions (Duke, Ohio State, Roswell Park, Dana-Farber, and Vermont) underwent RPFNA from July 1, 2007 to June 30, 2008. Duplicate bilateral RPFNA was performed on each woman by a single investigator on a single day. Masood Cytology Index score was assessed by a single blinded cytopathologist. Results: There was a high degree of statistical agreement in the Masood Cytology Index scores of duplicate RPFNA samples from the same breast, with a Spearman correlation coefficient of 0.8312 (p<0.0001). Importantly, while there was agreement in duplicate samples from the same breast, there was lack of agreement between duplicate samples from the opposite breast. Conclusions: This multi-institutional study demonstrates that RPFNA is a highly reproducible measure of breast cytology in a cooperative group cross-sectional trial. RPFNA did not demonstrate a high degree of agreement between breasts, suggesting that breast cancer risk and progression may occur at different rates in individual breasts from a single woman. These data provide important validation of the reproducibility of RPFNA in a multi-institutional cross-sectional study that included cohorts that varied in demographic composition. Important future directions will include a larger RPFNA cohort study and testing for the reproducibility of RPFNA samples with atypia before and after administration of chemoprevention agents. Citation Information: Cancer Prev Res 2010;3(1 Suppl):A20.