Introduction: Targeted therapies, including pembrolizumab and CDK4/6 inhibitors, have expanded treatment options for breast cancer subtypes such as triple-negative (TNBC) and hormone receptor-positive/HER2-negative cancers. However, their impact on surgical outcomes in two-stage prepectoral breast reconstruction remains unclear. This study evaluates surgical outcomes in patients receiving pembrolizumab or CDK4/6 inhibitors. Methods: A retrospective review was conducted of all patients at a single institution who underwent immediate two-stage prepectoral reconstruction at a single center between January 2018 and October 2024 with ≥3 months of follow-up. Exclusion criteria included autologous, delayed, or direct-to-implant reconstructions, and chemotherapy after implant exchange. Variables analyzed included cancer characteristics, treatments, and postoperative complications. Major complications were defined as those requiring readmission or reoperation. Statistical analyses were performed using Fisher’s Exact and Wilcoxon Rank Sum tests. Results: Of 472 patients, 27 received pembrolizumab and 30 received CDK4/6 inhibitors. Pembrolizumab had significantly higher seroma rates during expansion (44.4% vs. 27%, p=0.05). After implant exchange, major complications (26.3% vs. 8%, p=0.02) and reoperation rates (19.1% vs. 3.7%, p=0.01) were significantly higher. Patients receiving CDK4/6 inhibitors did not experience an increased risk of infection; in fact, the observed rate of minor infections was lower (0.0% vs. 12.4%, p=0.04), although no significant differences were seen in other outcomes. Conclusion: Pembrolizumab is a promising therapy for TNBC, but its association with increased seromas, major complications, and reoperations warrants further investigation. Use of CDK4/6 inhibitors was not associated with an increased risk of infection following tissue expander placement.
Ibrahim et al. (Fri,) studied this question.