Another radiation trial for older women. Radiation reduces local recurrence but not distant metastasis or overall survival. Again, hope one of our FCS radiation oncologists will share their thoughts in the comment section below.
Limited level 1 evidence is available on the omission of radiotherapy after breast-conserving surgery in older women with hormone receptor–positive early breast cancer receiving adjuvant endocrine therapy.
We performed a phase 3 randomized trial of the omission of irradiation; the trial population included women 65 years of age or older who had hormone receptor–positive, node-negative, T1 or T2 primary breast cancer (with tumors ≤3 cm in the largest dimension) treated with breast-conserving surgery with clear excision margins and adjuvant endocrine therapy. Patients were randomly assigned to receive whole-breast irradiation (40 to 50 Gy) or no irradiation. The primary end point was local breast cancer recurrence. Regional recurrence, breast cancer–specific survival, distant recurrence as the first event, and overall survival were also assessed.
A total of 1326 women were enrolled; 658 were randomly assigned to receive whole-breast irradiation and 668 to receive no irradiation. The median follow-up was 9.1 years. The cumulative incidence of local breast cancer recurrence within 10 years was 9.5% (95% confidence interval [CI], 6.8 to 12.3) in the no-radiotherapy group and 0.9% (95% CI, 0.1 to 1.7) in the radiotherapy group (hazard ratio, 10.4; 95% CI, 4.1 to 26.1; P<0.001). Although local recurrence was more common in the group that did not receive radiotherapy, the 10-year incidence of distant recurrence as the first event was not higher in the no-radiotherapy group than in the radiotherapy group, at 1.6% (95% CI, 0.4 to 2.8) and 3.0% (95% CI, 1.4 to 4.5), respectively. Overall survival at 10 years was almost identical in the two groups, at 80.8% (95% CI, 77.2 to 84.3) with no radiotherapy and 80.7% (95% CI, 76.9 to 84.3) with radiotherapy. The incidence of regional recurrence and breast cancer–specific survival also did not differ substantially between the two groups.
Omission of radiotherapy was associated with an increased incidence of local recurrence but had no detrimental effect on distant recurrence as the first event or overall survival among women 65 years of age or older with low-risk, hormone receptor–positive early breast cancer. (Funded by the Chief Scientist Office of the Scottish Government and the Breast Cancer Institute, Western General Hospital, Edinburgh; ISRCTN number, ISRCTN95889329. opens in new tab.)
Metronomic dose: low dose cytotoxic therapy at high frequency was studied in combination with an AI (cape at 500mg TID) and showed superiority over AI single agent, this may be an option for patients not tolerating CKD4/6 inhibitors.
In summary: It did not work in those patients with stages II-III.
The INSEMA trial showed that for early stage, T1-T2 clinically node negative breast cancer, sentinel lymph node biopsies should not be mandatory, and best clinical judgement can be used.
Imlunestrant (novel oral SERD) was active in patients with an ESR1 mutations, but otherwise did not offer a benefit in this population of women with ER+ HER2-neg MBC. Overall survival (OS) data is pending with further follow up.
Yet another combination to consider after CDK4/6i + ET in HR+ MBC!
FCS Hematology Oncology Review creates a platform for our physician network to observe the most recent articles and studies available in the oncology and hematology world. By sharing these articles we are building our wealth of knowledge of new observations and treatments as they come available.
