Potential for Surgery Omission in Select Breast Cancer Patients after Ablative Radiation

Recent findings from a Phase 2 clinical trial suggest that certain patients with early-stage hormone receptor-positive (HR+) and HER2-negative breast cancer may safely forgo surgery following ablative radiation therapy. This study, led by the University of Texas MD Anderson Cancer Center, was presented at the European Society for Radiotherapy and Oncology (ESTRO) conference in Stockholm by Dr Simona Shaitelman, a professor of Breast Radiation Oncology.

The trial focused on a group of 20 patients, all of whom received initial endocrine therapy followed by ablative radiation. Remarkably, the disease control rate was reported at 100% over a median follow-up period exceeding three years. The participants, with a median age of 71, had stage 1 unicentric breast cancer with favorable tumor biology. Of the 19 patients who underwent biopsy, 53% achieved a pathologic complete response, and no breast cancer-related deaths were recorded among those who did not undergo surgery.

Dr Shaitelman highlighted that these results underscore significant advancements in radiation therapy delivery, which now enable clinicians to administer higher and more precise doses effectively. This can lead to fewer treatment sessions and potentially render surgery unnecessary for some patients. Enhanced understanding of breast cancer biology also plays a critical role in identifying which patients might respond favorably to combined treatments of endocrine therapy and radiation.

The trial identified three key biomarkers predictive of a complete response: smaller tumor size following initial hormone therapy, significant volume reduction before radiation, and greater expression of estrogen. These indicators may assist clinicians in selecting patients who could benefit from non-operative treatments.

Given the promising results, Dr Shaitelman advocated for more extensive research through a multi-institutional study to refine patient selection for non-surgical approaches in breast cancer management. She emphasized the global accessibility of radiation therapy and its untapped potential as a definitive treatment, advocating for rigorous studies of these alternatives to assess if they can match the outcomes of traditional surgical methods.