Does the Type of Reconstruction Matter? A Propensity Score Matched Analysis of Immediate Post-mastectomy Implant and Flap Reconstruction.

Overview

abstract

BACKGROUND: No randomized controlled trials have compared implant and flap reconstruction. Recently, worse longitudinal outcomes have been suggested for flap reconstruction. We compared long-term oncologic outcomes of post-mastectomy breast reconstruction using propensity score matching. METHODS: A retrospective study of post-mastectomy reconstruction was achieved using the Weill Cornell Breast Cancer Registry between 1998 and 2019. Patients were matched using propensity scores based on demographic, clinical, and surgical characteristics. Kaplan-Meier estimates, Cox-regression models, and restricted mean survival times (RMST) were used to evaluate patient outcomes. RESULTS: Before matching, 1395 implant and 586 flap patients were analyzed. No difference in overall survival and recurrence were observed. Multivariable models showed decreased survival for Medicare/Medicaid (HR: 3.09; 95% CI: 1.63, 5.87; P <.001), pathological stage II (HR: 2.98; 95% CI: 1.12, 7.90; P = .028), stage III (HR: 4.88; 95% CI: 1.54, 15.5; P = .007), 11 to 20 lymph nodes positive (HR: 3.66; 95% CI: 1.31, 10.2; P = .013), >20 lymph nodes positive (HR: 6.41; 95% CI: 1.49, 27.6; P = .013). RMST at 10 years post-flap reconstruction showed 2 months of decreased survival time compared to implants (9.56 vs 9.74 years; 95% CI: -.339, -.024; P = .024). After matching, 563 implant and 563 flap patients were compared. Reconstruction was not associated with overall survival and recurrence. RMST between implant and flap reconstruction showed no difference in each 5-year interval over 20 years. CONCLUSIONS: Post-mastectomy breast reconstruction was not associated with a difference in long-term oncologic outcomes over a twenty-year period.