Abstract P4-12-10: Uptake and outcomes of multiplex testing for breast cancer susceptibility
Authors: Bradbury Angela R , Patrick-Miller Linda , Egleston Brian L , Brandt Amanda , Long Jessica , Powers Jacquelyn , Stopfer Jill , DiGiovanni Laura , Brower Jamie , Domchek Susan M 
Published: May 2015

Background: New counseling models for multiplex genetic testing for breast cancer susceptibility are needed. Further, the risks, benefits and utilities of multiplex genetic panels are unknown.

Purpose: To obtain stakeholder feedback on an innovative tiered-binned model for pretest counseling and informed consent for multiplex testing and to evaluate the uptake of, cognitive and affective responses to and perceived utility of panel testing.

Methods: Patients previously BRCA1/2- or BRCA1/2 untested completed in-person pre-test (V1) and post-test counseling (V2) and surveys regarding the novel counseling model and evaluating cognitive and affective responses to, and perceived utility of the 26 gene Myriad MyRisk panel for cancer susceptibility.

Results: 49 patients (62% of eligible) enrolled and completed V1. 38% of decliners were not interested in panel testing. BRCA1/2- were more likely to proceed with MyRisk (89%) than BRCA1/2 untested (48%, p&lt;0.01). Although not statistically significant, those who declined panel testing after V1 had higher anxiety, depression and cancer worry, but no difference in knowledge. They also had lower perceived utility (p=0.005). Most patients would not change anything about their V1 (86%) or V2 (91%) counseling. Surveys suggest that patients value the engagement, personalization, organization and visual aids of the novel counseling model. Potential refinements include enhancing assessments of informational overload, confusion and psychosocial needs, particularly with uncertain results. As shown in Table 1, event anxiety, depression, uncertainty and cancer worry did not change, while general anxiety decreased. Knowledge increased and perceived utility and satisfaction decreased significantly. Exploratory analyses by results to date (positive = 5; VUS = 9; negative =22), suggest no difference in uncertainty by test result. Patients with a positive result might experience greater event anxiety and have less decline in perceived utility (p=0.02) than those with a negative or VUS result.

Table 1 BaselinePost V1Post V2 Mean (SD)Mean (SD)Mean (SD)General Anxiety6.8 (3.9)*6.1 (4.0)*  7.2 (3.5)*6.1 (3.6)*5.8 (4.2)*General Depression2.6 (3.0)2.3 (2.6)  2.6 (2.9)2.3 (2.6)2.9 (3.6)Event Anxiety37.1 (9.6)37.7 (9.5)  37.0 (8.9)37.3 (8.5)37.3 (9.4)Cancer Worry18.3 (15.7)16.9 (14.1)  18.4 (15.4)15.7 (14.1)6.6 (14.7)Knowledge (K) Total61.8 (6.1)**63.9 (6.4)**  62.1 (6.7)**64.1 (6.8)**66.3 (6.9)**K-Inheritance29.5 (3.2)30.0 (3.2)  29.7 (3.5)29.8 (3.3)30.3 (3.7)K-Benefits12.0 (1.4)12.3 (1.8)  12.0 (1.4)12.4 (1.7)12.4 (1.9)K-Limitations20.3 (3.2)**21.6 (2.8)**  20.4 (3.4)**21.9 (3.0)**23.6 (2.6)**Satisfaction 42.8 (3.8)   42.9 (3.6)*41.4 (2.6)*Uncertainty7.5 (4.3)6.9 (4.6)  7.7 (4.0)6.5 (4.5)6.7 (4.6)Perceived Utility 37.2 (7.9)   37.7 (7.0)*33.8 (8.6)**p,0.05, **p&lt;0.001

Conclusion: With a tiered-binned counseling model, patients experience increased knowledge. Uptake of panel testing varies by prior testing and potentially by patient affective factors. Most patients do not experience negative psychological responses, although this may vary by test result. Declines in satisfaction and perceived utility may also vary by test result and may reflect the current unclear utility and uncertainty of multiplex testing.

Citation Format: Angela R Bradbury, Linda Patrick-Miller, Brian L Egleston, Amanda Brandt, Jessica Long, Jacquelyn Powers, Jill Stopfer, Laura DiGiovanni, Jamie Brower, Susan M Domchek. Uptake and outcomes of multiplex testing for breast cancer susceptibility [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 P4-12-10.