Abstract OT3-09-03: The PREDICT registry: A prospective registry study to evaluate the effect of the DCISionRT test on treatment decisions in patients with DCIS following breast conserving therapy

Background: The benefits of adjuvant radiation therapy (RT) in DCIS patients treated with breast conserving surgery (BCS) remains controversial. Although there is level I evidence supporting the role of RT in reducing the risk of local recurrence, the incremental absolute benefit is variable. Current treatment guidelines generally recommend RT for all patients having BCS. When considered in the context of the economic, health-related, and quality-of-life costs associated with RT, it is critical to identify patients who are at low enough risk to consider foregoing RT. It is important to develop prognostic tools to better assess risk and understand the impact such a tool would have on treatment decisions. The DCISionRT™ Test (PreludeDx, Laguna Hills, CA) is a biologic signature that provides a validated score for assessing 10-year risk of recurrence and RT benefit using individual tumor biology in conjunction with clinical and pathologic risk factors. Trial Design: This is a prospective cohort study for patients diagnosed with ductal carcinoma in situ (DCIS) of the breast. Treating physicians complete a treatment recommendation survey before and after receiving DCISionRT test results. Test results, treatment recommendations, patient preferences and clinicopathologic features are stored in a de-identified registry for future analysis of data across participating institutions from a variety of geographic regions in the US. The study will also collect 5- and 10-year recurrence and survival data. Eligibility Criteria: The study includes females over the age of 25 who are candidates for BCS and eligible for RT and/or systemic treatment with sufficient tissue to generate test results. Subjects must not have been previously treated for DCIS or have previous or current invasive or micro-invasive breast cancer. Specific Aims: The primary objective of this study is to create a de-identified database of patients, test results, treatment decisions and outcomes that can be queried to determine the clinical utility of the DCISionRT Test in actual clinical use for the management of DCIS. The primary endpoints are changes in treatment recommendations for surgical, radiation and hormonal therapy after the physician and patient have reviewed the DCISionRT test results, including subgroup analysis by physician type (surgeon, radiation oncologist or tumor board). Secondary endpoints are identification of the key drivers for treatment recommendations, including age, size, grade, architecture, necrosis, palpability, presentation, hormone receptor status, race, ethnicity, family history, etc. Statistical Methods: Study results will be analyzed by summary descriptive statistics, such as patient counts, percentages, means, etc. Changes in treatment recommendations will be assessed using McNemar9s chi-squared test for symmetry of rows and columns in a two-dimensional contingency table with an alpha level of 0.05. Differences in recurrence-free and overall survival will be evaluated by Kaplan-Meier survival analysis using the logrank test and/or the Cox Proportional Hazards model. A planned early interim analysis based on the first 200 patients has been recently completed and reported - data are available upon request (contact Steven Shivers, PhD, sshivers@preludedx.com.) Accrual: As of July 1, 2019, 319 patients have been accrued from 56 physicians at 25 institutions. Twenty-two additional institutions are currently in the process of joining the study. We are planning to accrue up to 2,500 patients from up to 100 institutions. Contact Information: We are actively recruiting institutions for participation. For more information, please contact: Mary Kay Hardwick, mkhardwick@tmebcn.com. Citation Format: Steve C Shivers, Pat Whitworth, Rakesh Patel, Troy Bremer, Charles E Cox. The PREDICT registry: A prospective registry study to evaluate the effect of the DCISionRT test on treatment decisions in patients with DCIS following breast conserving therapy [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr OT3-09-03.