Post-Conference Perspectives: Breast Cancer Recurrence Score - Episode 5
Joseph A. Sparano, MD: I think perhaps the greatest potential future application or expansion of the results of TAILORx involve the application to patients who have node-positive disease. In fact, there was an entire session at the 2018 San Antonio Breast Cancer Symposium devoted specifically to this topic. We do know that there are prospective trials that have been done in patients with node-positive disease, the PlanB trial namely, demonstrating that women who have a low recurrence score or very low recurrence score treated with endocrine therapy alone do very, very well, not unlike what was observed in the MINDACT trial for patients with 1 to 3 positive nodes who had a low 70-gene MammaPrint score.
So this suggests that biology matters, biology is important, and although anatomy is prognostic and provides information regarding recurrence risk and prognosis, it doesn’t provide information that necessarily is predictive for benefit from chemotherapy, which is something that the 21-gene assay does. So I do see potential application here of these findings in patients with node-positive disease. There have been trials that have been completed. The RxPONDER trial has been completed, and we should have a more definitive answer on this question. But I do see clinicians developing a greater comfort level with sparing the use of adjuvant chemotherapy in patients with low-volume, node-positive disease, particularly postmenopausal women who have very favorable biology based on a very low recurrence score.
The 21-gene recurrence score provides very robust prognostic and predictive information. However, even patients who have a low or intermediate recurrence score—if there is such a thing as an intermediate recurrence score anymore—still have about a 3% to 5% risk of distant recurrence. So I do think we need to do more work to try and identify why those 3% to 5% of patients who have a very favorable biology relapse. Can we improve the recurrence score by adding in other genes, by looking at adding other markers that evaluate other biological processes? So I think that’s part of some of the additional work that can be done.
Transcript Edited for Clarity