The Impact of Neoadjuvant Systemic Treatment on Postoperative Complications in Breast Cancer Surgery

Abstract Purpose: The aim of the study was to analyse the impact of neoadjuvant systemic treatment (NST) on postoperative complications and the beginning of adjuvant treatment. Methods: This study includes data from a prospectively maintained database including patients with breast cancer (BC) stage I-IV with or without NST undergoing breast cancer surgery between January 2010 and September 2021. Results: Out of 517 enrolled patients, 77 received NST, 440 had primary breast surgery. After NST patients underwent surgery after a meantime of 34 days (26.5 – 40 days). No statistical significance could be found comparing the complication grading according to the Clavien Dindo classification. The complications were most frequently rated as grade 3b. There were no complications with grade 4 or higher. When differentiating into short and long-term, the overall rate of short-term complications was 20.3% with no significant difference between the two groups (20.8% vs. 20.2%). Regarding long-term complications, there was more impairment of shoulder mobility (26.0% vs. 9.5%, p = < 0.001) and chronic pain (42.9% vs. 28.6%, p = < 0.016) for patients with NST. The beginning of the administration of the adjuvant treatment was comparable in both groups (46.3 days vs. 50.5 days). Conclusion: In our cohort, complications between both groups were comparable according to Clavien Dindo. This study shows that NST has no negative impact on postoperative short-term complications and most importantly did not lead to a delay of the beginning of adjuvant treatment. Therefore, NST can be safely admitted, even when followed by extensive breast reconstruction surgery.