Preoperative breast MRI to identify candidates for omission of postoperative radiotherapy among early breast cancer patients

Adjuvant breast radiotherapy as a standard component of breast-conserving surgery (BCS) treatment for early cancer can overtreat many women. Breast MRI is the most sensitive modality to assess local tumor burden. The prospective PROSPECT trial, at four centers in Australia, found that among 201 breast cancer patients who were truly unifocal on MRI and pT1N0 or N1mi on pathology, omission of radiotherapy after BCS resulted in only one local recurrence after 4.5 years and one more after 7.5 years. The authors conclude that these results suggest that in the treatment of women with unifocal breast cancer on MRI and favorable results on pathology, radiotherapy after BCS can be safely omitted.