Dr Alexey Aleshin Discusses Lingering Struggles in Pinpointing Biomarkers for Breast Cancer Reoccurrence

Attention on finding biomarkers for metastatic reoccurrence of breast cancer needs to be directed at women with a high risk of this happening in the course of their disease, noted Alexey Aleshin, MD, senior medical director of Oncology at biotech giant Natera.

Transcript

Why is predicting early metastatic reoccurrence such an issue in breast cancer?

Breast cancer is an extremely heterogeneous disease, and there're so many subtypes. So, pathological CR [complete response] status is a great biomarker, not only for response to therapy but for long-term outcomes. Really, it's not perfect, especially for the patients who do not achieve path CR. That's a wide spectrum of women. Some have a little bit of tumor left at the time of recession and some with a lot. Still, the majority of these women's [cancer] do not recur. So, better parsing that subgroup into the women with the highest risk for recurrence versus those who are likely cured prior to therapy and surgery alone is critical for future clinical trials to really fundamentally alter how these women are treated and surveiled in the adjuvant setting.

Are there any obstacles that need to be overcome that you haven't addressed yet?

I think the biggest obstacle in the space is replicability of the data. I think it's not enough to share the data once. I think we need to basically do additional validation studies. This finding is no exception, and excitingly, just at this past year's San Antonio Breast Cancer [Symposium], the follow-on study results were presented from an additional I-SPY2 cohort. The results were highly consistent, again showing that the majority of women's ctDNA [circulating tumor DNA] can be detected, as well as monitored, over time. The relationship described in the current publications also held up, namely that women with early ctDNA clearance have improved outcomes and higher rates of pathological CR, as well as women with residual tumor DNA prior to surgery having worse outcomes long term.