Top Line: Is there better selection criteria for omission of breast radiation than age and basic pathologic features?
The Study: LUMINA is a prospective multicenter cohort study that enrolled women 55 and older who had lumpectomy with at least 1 mm margins for T1N0, grade 1-2 breast cancer. Furthermore, patients had to have luminal A subtype defined as ER≥1%, PR>20%, and Ki67≤13.25%. Out of 727 patients who met the clinical criteria, 501 (69%) had luminal A subtype and received adjuvant endocrine therapy without radiation. There was no randomized comparator arm, but the rate of local recurrence was just 2.3% at 5 years. There were almost as many contralateral breast cancers (1.9%) and more than twice as many second non-breast cancers. Recurrence-free and overall survival were both 97% at 5 years.
TBL: The rate of local recurrence for women 55 and older with T1-2N0, luminal A breast cancer is very low at 5 years with adjuvant endocrine therapy alone, but the verdict remains out on whether several years of endocrine therapy or a few days of radiation is the better value. | Whelan, ASCO 2022