Older patients with hormone receptor-positive breast cancer who did not receive radiation therapy after breast-conserving surgery had higher rates of local recurrence but similar 10-year survival rates when compared to patients who received postoperative radiation therapy, according to updated 10-year data from the PRIME II study, presented at the 2020 San Antonio Breast Cancer Symposium

Getty Images


December 15, 2020 — Older patients with hormone receptor-positive breast cancer who did not receive radiation therapy after breast-conserving surgery had higher rates of local recurrence but similar 10-year survival rates when compared to patients who received postoperative radiation therapy, according to updated 10-year data from the PRIME II study, presented at the 2020 San Antonio Breast Cancer Symposium, held Dec. 8-11.

"Over half the patients diagnosed with breast cancer in developed countries are over the age of 65 years," said Ian Kunkler, FRCPE, professor of clinical oncology at the Western General Hospital, University of Edinburgh. Despite the less aggressive breast cancers typically diagnosed in this population, most patients who undergo breast-conserving surgery continue to be treated with whole breast radiation therapy after surgery, he explained. "We were interested in determining whether older patients with low-risk breast cancer could be spared radiation therapy."

The PRIME II study enrolled 1,326 patients with non-metastatic hormone receptor (HR)-positive breast cancer. All patients were at least 65 years of age, had undergone breast-conserving surgery, and were receiving adjuvant hormone therapy. Patients were randomly assigned to either receive or not receive radiation therapy after surgery. Kunkler and colleagues previously reported greater rates of local recurrence (defined as recurrence in the same breast as the primary tumor) in patients who did not receive radiation therapy, but no significant differences in overall survival, distant metastases, or new breast cancers between the two arms after five years.

The latest data presented at the symposium report results from a 10-year follow-up. Kunkler reported that the rate of local recurrence after 10 years was significantly greater in patients who did not receive radiation therapy compared with patients who did (9.8 percent vs. 0.9 percent).

While postoperative radiation therapy affected the risk of local recurrence, it did not significantly impact certain other clinical outcomes. After 10 years, patients who did not receive radiation therapy had similar rates of distant metastasis (1.4 percent vs. 3.6 percent), recurrence in the opposite breast (1.0 percent vs. 2.2 percent), and overall survival (80.4 percent vs. 81.0 percent) as patients who did receive radiation therapy. Most deaths were due to reasons other than breast cancer.

"We found that omitting postoperative radiation therapy did not compromise survival or increase the risk of distant metastasis," said Kunkler. "Based on these results, we believe that omission of radiation therapy after breast-conserving surgery should be an option for older patients with localized, HR-positive breast cancer who are receiving adjuvant hormone therapy and meet certain clinico-pathological criteria."

A limitation of the study is that only a few patients with grade 3 tumors were recruited, so the results of the study may not be applicable to patients with high-grade tumors or with tumors larger than 3 centimeters. An additional limitation is that data on comorbidities or adherence to adjuvant hormone therapy were not collected.

For more information: www.aacr.org


Related Content

News | Radiation Therapy

June 19, 2024 — RaySearch Laboratories AB announced a milestone in radiotherapy technology where RaySearch’s RayStation ...

Time June 19, 2024
arrow
News | Breast Imaging

June 18, 2024 — Delphinus Medical Technologies, a pioneering medical imaging company that developed the SoftVue Breast ...

Time June 18, 2024
arrow
News | Artificial Intelligence

June 17, 2024 — Avenda Health, an AI healthcare company creating the future of personalized prostate cancer care ...

Time June 17, 2024
arrow
News | Proton Therapy

June 14, 2024 — Atlantic Health System, an integrated health care system setting standards for quality health care in ...

Time June 14, 2024
arrow
News | PET Imaging

June 14, 2024 — Positron Corporation, a leading molecular imaging medical device company offering PET and PET-CT ...

Time June 14, 2024
arrow
News | MRI Breast

June 12, 2024 — Royal Philips recently announced the 1,111th installation of its revolutionary BlueSeal 1.5T magnet ...

Time June 12, 2024
arrow
News | FDA

June 10, 2024 — Siemens Healthineers announces the Food and Drug Administration clearance of the Biograph Trinion, a ...

Time June 10, 2024
arrow
News | Breast Imaging

June 7, 2024 — Scholars and studies funded by Susan G. Komen(R), the world’s leading breast cancer organization ...

Time June 07, 2024
arrow
News | Radiopharmaceuticals and Tracers

June 7, 2024 — Shine Technologies, LLC, a pioneer in next-generation fusion-based technology, today announced a new ...

Time June 07, 2024
arrow
News | Breast Density

June 6, 2024 — Subsequent rounds of abbreviated breast MRI (AB-MR) screening in patients with dense breasts had lower ...

Time June 06, 2024
arrow
Subscribe Now