Piper 2016.

Study characteristics
Methods	Retrospective single‐centre matched cohort 2001 to 2009 University of California, San Francisco, USA 98 participants
Participants	Inclusion: Patients with breast cancer undergoing breast‐conserving surgery Exclusion: Patients without negative margins at the time of initial surgery
Interventions	Intervention: Volume displacement ‐ simultaneous partial mastectomy and bilateral reduction mammoplasty, (n = 49) Control: standard BCS: WLE, (n = 49)
Outcomes	Primaryoutcomes (median follow‐up 60 months): Local recurrence Overall survival Secondaryoutcomes Re‐excisions Recall rates Otheroutcomes: Findings on follow‐up imaging Margins
Notes	No disclosures/funding declared Authors were contacted requesting full dataset for primary outcomes