Variability of Biological Parameters Between Tumor Biopsy & Surgical Samples in Breast Cancer Patients

A real-world study reported at the ESMO Breast Cancer 2023 Annual Congress identified a risk for inappropriate therapeutic decision-making resulting from an alarmingly high rate of false-negative tests coming from biopsy specimens looking for biological parameters such as PR and HER2.  Study researchers at the University of Catania suggested tumor heterogeneity was a big reason why markers like PR and HER2 were being missed that subsequently turned up in surgical specimens. But biopsy technique was also an issue, they concluded. OncTimesTalk correspondent Peter Goodwin caught up with one of the study authors, Federica Martorana, Assistant Professor of Medical Oncology. Together with lead author Sabrina Nucera from the University of Messina, and their co-authors, she said they retrospectively analyzed data from samples—collected over a 10 year period—for which both biopsy and surgical specimens were available. They excluded patients receiving neoadjuvant therapy and looked for differences in the detection of estrogen and progesterone receptors plus Ki67, as well as HER2 score, tumor grade, and intrinsic subtype. As a result, they had to re-classify 25 out of 61 cases of luminal B-like breast cancer that turned out mostly to be luminal A, with three of them being triple-positive.