A chance to cut.

Top Line: Back at ASCO ‘20, we were disappointed by results from the EA2108 trial, which showed no benefit to early local therapy for de novo metastatic breast cancer.

The Study: Here we have the full publication with subset analyses. EA2108 makes the fourth reported randomized trial asking whether locoregional therapy improves survival in metastatic breast cancer, but only one (MF07-01) reported an improvement. In EA2108, 390 patients were enrolled, and 256 (66%) moved on to randomization after not progressing on initial systemic therapy. Most (60%) had hormone receptor positive, HER2-negative disease. They were randomized to continued systemic therapy or locoregional therapy consisting of standard surgery with adjuvant radiation as indicated by the extent of locoregional disease. Most had mastectomy (70.1%), and 58.7% received post-mastectomy radiation while 84.4% received post-lumpectomy radiation. In the systemic therapy arm, one in five ended up receiving delayed locoregional therapy. At 3 years, there was no difference in overall survival with locoregional therapy (68.4% v 67.9%). Across almost all subgroups, there was no indication of a benefit with locoregional therapy. The exception was a small proportion of patients with triple negative breast cancer who actually had a higher risk of mortality with locoregional therapy (HR 3.33). A minority of patients (12.2%) had oligometastatic disease (3 or fewer lesions in a single organ), and they did not have improved survival with locoregional therapy. When it came to locoregional progression at 3 years, though, the rate was less than half with locoregional therapy (16.3% v 39.8%). Importantly, locoregional therapy led to more symptoms without a major impact on patient worry about tumor growth. At 18 months, quality of life (using the FACT-B TOI) was significantly better in the systemic therapy arm.

TBL: While locoregional therapy improves locoregional control for patients with de novo metastatic breast cancer, there is no improvement in overall survival or quality of life. | Khan, J Clin Oncol 2022