ObjectiveTo explore the clinical efficacy of volume displacement techniques for breast defects following breast conserving surgery. MethodsAfter inclusion and exclusion, the patients with breast defects following breast conserving surgery in the Minda Hospital of Hubei Minzu University from February 2013 to March 2020 were retrospectively enrolled, and were assigned into a volume displacement group and volume replacement group according to different surgical techniques. Then the outcomes were compared between the two groups, including short-term efficacy (incision length, operation time, intraoperative blood loss, volume of resected specimen, cosmetic effect, patients’ subjective satisfaction, total postoperative complications, and total hospitalization time) and long-term efficacy (local recurrence rate, 3-year tumor-free survival, and 3-year overall survival). ResultsA total of 208 eligible patients were included in this study, including 105 in the volume displacement group and 103 in the volume replacement group before propensity score matching (PSM); after PMS, a total of 62 patients were enrolled, including 33 in the volume displacement group and 29 in the volume replacement group. No statistical difference was reported in the baseline data between two groups (P>0.05), except that the maximum diameter of lesion in the volume displacement group was smaller than that in the volume replacement group (P<0.05). The incision length, operation time, total hospitalization time, total postoperative complication rate, local recurrence rate, 3-year tumor-free survival rate, and 3-year overall survival rate had no statistical differences between the two groups (P>0.05), whereas the intraoperative blood loss was less (t=3.294, P=0.002) and the volume of resected specimen was smaller (t=2.030, P=0.047) in the volume displacement group as compared with the volume replacement group, and the cosmetic effect and patients’ subjective satisfaction were better in the volume displacement group as compared with the volume replacement group (Z=2.297, P=0.022; Z=2.256, P=0.024). ConclusionThe study analysis with small size samples reveals that volume displacement technique for breast defects following breast conserving surgery can achieve a good cosmetic effect and high patients’ subjective satisfaction without increasing risk of postoperative complications and tumour recurrence, which demonstrates a good long-term efficacy profile.