Impact of rapid genetic counselling and testing on the decision to undergo immediate or delayed prophylactic mastectomy in newly diagnosed breast cancer patients: findings from a randomised controlled trial

Abstract

Background:Female breast cancer patients with a BRCA1/2 mutation have an increased risk of contralateral breast cancer. We investigated the effect of rapid genetic counselling and testing (RGCT) on choice of surgery.Methods:Newly diagnosed breast cancer patients with at least a 10% risk of a BRCA1/2 mutation were randomised to an intervention group (offer of RGCT) or a control group (usual care; ratio 2 : 1). Primary study outcomes were uptake of direct bilateral mastectomy (BLM) and delayed contralateral prophylactic mastectomy (CPM).Results:Between 2008 and 2010, we recruited 265 women. On the basis of intention-to-treat analyses, no significant group differences were observed in percentage of patients opting for a direct BLM (14.6% for the RGCT group vs 9.2% for the control group; odds ratio (OR) 2.31; confidence interval (CI) 0.92–5.81; P=0.08) or for a delayed CPM (4.5% for the RGCT group vs 5.7% for the control group; OR 0.89; CI 0.27–2.90; P=0.84). Per-protocol analysis indicated that patients who received DNA test results before surgery (59 out of 178 women in the RGCT group) opted for direct BLM significantly more often than patients who received usual care (22% vs 9.2% OR 3.09, CI 1.15–8.31, P=0.03).Interpretation:Although the large majority of patients in the intervention group underwent rapid genetic counselling, only a minority received DNA test results before surgery. This may explain why offering RGCT yielded only marginally significant differences in uptake of BLM. As patients who received DNA test results before surgery were more likely to undergo BLM, we hypothesise that when DNA test results are made routinely available pre-surgery, they will have a more significant role in surgical treatment decisions.

Does rapid genetic counseling and testing in newly diagnosed breast cancer patients cause additional psychosocial distress? results from a randomized clinical trial

“…As reported in our previous work, this expectation was not met, based on ITT analyses. 12 On the basis of the per-protocol analysis of our clinical data, significant group differences were observed in the uptake of CPM. That is, women who received their DNA test results before surgery (59/178 women in the RGCT group) opted significantly more often for direct bilateral mastectomy (BLM) than patients who received UC (22 vs. 9.2%; OR 3.09, CI 1.15-8.31, P = 0.03).…”

“…We included patients with unilateral and bilateral breast cancer because a bilateral mastectomy is not always necessary in the case of bilateral breast cancer. 12 …”

“…12,13 Briefly, between November 2008 and December 2010, eligible patients were recruited from 12 hospitals in the Netherlands. The study was approved by the medical ethics committees of all participating hospitals, and all patients provided informed consent before randomization.…”

“…Randomization was stratified by hospital. 12,13 Given the nature of the intervention, blinding of the participants was not possible. The RGCT group was offered an appointment with a clinical geneticist within 5 working days after recruitment and the opportunity to undergo rapid DNA testing, with test results provided within approximately 4 weeks.…”

“…We recently reported the results of the behavioral outcomes from this trial. 12 Briefly, we found that when RGCT is offered routinely to high-risk breast cancer patients, almost all women accept rapid genetic counseling and approximately 40% opt for a rapid DNA test of the BRCA1/2 genes. Based on an intention-to-treat (ITT) analysis, RGCT did not have a significant impact on choice of primary surgery.…”