PURPOSE: Prepectoral implant-based breast reconstruction is being increasingly performed over subpectoral postmastectomy reconstruction because of the reduced invasiveness of the procedure, postoperative pain and risk of animation deformity. Radiation therapy is a well-known risk factor for complications in implant-based breast reconstruction. However, the effect of premastectomy versus postmastectomy radiation therapy on outcomes after prepectoral breast reconstruction has not been well-defined. The purpose of this study was to compare the impact of pre- versus postmastectomy radiation therapy on outcomes after prepectoral implant-based breast reconstruction.
METHODS: A retrospective chart review was performed of all patients who underwent prepectoral implant-based breast reconstruction with inferior dermal flap and acellular dermal matrix performed by a single surgeon from 2010 to 2019. Demographic, clinical, and operative data were reviewed and recorded. Outcomes were assessed by comparing rates of capsular contracture, infection, seroma, hematoma, dehiscence, mastectomy skin flap necrosis, rippling, implant loss, local recurrence, and metastatic disease between patients receiving pre- and postmastectomy radiation therapy and patients not receiving radiation therapy.
RESULTS: During the study period, 369 patients (592 breasts) underwent prepectoral implant-based breast reconstruction. Twenty-six patients (28 breasts) received premastectomy radiation, 45 patients (71 breasts) received postmastectomy radiation, and 305 patients (493 breasts) did not receive either pre- or postmastectomy radiation therapy. Patients with premastectomy radiation had higher rates of seroma (14.3% versus 0.2%; P < 0.001), minor infection (10.7% versus 1.2%; P = 0.009), implant loss (21.4% versus 3.4%; P = 0.001), and local recurrence (7.1% versus 1.0%; P = 0.049), when compared with those without radiation. Patients receiving premastectomy radiation also had a capsular contracture rate 3 times that of nonradiated patients (10.7% versus 3.2%; P = 0.075), although the difference was not significant. Patients with postmastectomy radiation had higher rates of major infection (8.4% versus 2.4%; P = 0.017), capsular contracture (19.7% versus 3.2%; P < 0.001), implant loss (9.9% versus 3.4%; P = 0.022), and local recurrence (5.6% versus 1.0%; P = 0.018), when compared with patients without radiation. Outcomes after prepectoral implant-based breast reconstruction were comparable between pre- and postmastectomy radiation therapy groups, respectively, with regard to major infection (7.1% versus 8.4%; P = 1.000), dehiscence (3.6% versus 1.4%; P = 0.488), major mastectomy skin flap necrosis (7.1% versus 2.8%; P = 0.317), capsular contracture (10.7% versus 19.7%; P = 0.382), implant loss (21.4% versus 9.9%; P = 0.184), and local recurrence (7.1% versus 5.6%; P = 1.000). However, patients with premastectomy radiation had a higher rate of seroma compared with those receiving postmastectomy radiation therapy (14.3% versus 0%; P = 0.005).
CONCLUSIONS: In prepectoral implant-based breast reconstruction, both pre- and postmastectomy radiation therapy were associated with higher rates of infection and implant loss compared with nonradiated patients. However, premastectomy radiation was associated with a higher rate of seroma compared with nonradiated and postmastectomy radiation therapy groups. Postmastectomy radiation was associated with a higher rate of capsular contracture when compared with nonradiated patients and a comparable rate of capsular contracture when compared with premastectomy radiation therapy patients.