Genetic testing in women with early-onset breast cancer: a Traceback pilot study

Abstract

In Sweden, a Traceback approach, i.e., a retrospective genetic outreach activity, among cancer patients is not normally used in clinical practice. In this pilot study, we wanted to evaluate a Traceback strategy for possible future clinical implementation and investigate why not all women with early-onset breast cancer underwent genetic testing when they were first diagnosed. Out of all women (n\u2009=\u2009409) diagnosed with breast cancer at\u2009≤\u200935 years in Southern Sweden between 2000 and 2017, 63 had not previously been tested. These women were offered an analysis of the genes BRCA1, BRCA2, PALB2, CHEK2, and ATM through a standardized letter. Subsequently, women with normal test results were informed through a letter and carriers of pathogenic variants were contacted through a telephone call and offered in-person genetic counseling. All tested women were asked to complete a follow-up questionnaire regarding previously not having attended genetic counseling and testing and their experiences of the current retrospective approach. Out of the invited women, 29 (46%) underwent genetic testing and 27 (43%) answered the questionnaire. Pathogenic variants were identified in BRCA1 (n\u2009=\u20092), CHEK2 (n\u2009=\u20091), and ATM (n\u2009=\u20091). The main reason for previously not having undergone genetic testing was not having received any information from their physicians. Most study participants were satisfied with both written pre- and post-test information. The process with retrospective identification, written pre-test information, and genetic testing, followed by in-person counseling for carriers of pathogenic variants only, was well accepted. This has implications for future Traceback implementation programs.