Predictive biomarkers of recurrence may not be useful for de-escalating treatment in DCIS

Tanjina Kader, PhD, Peter MacCallum Cancer Centre, Melbourne, Australia, discusses recent findings from a molecular analysis of primary tumors in ductal carcinoma in situ (DCIS). It was found that 18% of de novo primary tumors were nonclonal or not genetically related to the primary DCIS. Tumor clonality was not significantly associated with the grade of the primary DCIS, estrogen receptor (ER), or HER2 status, or prior radiotherapy treatment, suggesting that there is a genetic predisposition or environmental factor that renders some patients highly susceptible to developing new tumors. This has clinical implications, where previously used prognostic biomarkers may not predict recurrence and result in under-treatment of that patient. This interview took place at the American Association for Cancer Research Annual Meeting in New Orleans, LA.