Are thin flaps still a contraindication? Early outcomes of prepectoral DTI reconstruction in a large single-center cohort

Introduction: Prepectoral direct-to-implant (DTI) breast reconstruction has gained popularity due to reduced morbidity and improved aesthetic and functional outcomes. However, thin mastectomy flaps (<1 cm, R1 following the Rancati classification) are traditionally considered at higher risk of complications, often leading surgeons to prefer subpectoral or staged approaches. This study evaluates whether prepectoral DTI reconstruction can be safely performed in patients with thin mastectomy flaps, challenging the traditional view that these patients are unsuitable candidates. Materials and methods: A retrospective single-center analysis was conducted on 1239 patients undergoing immediate prepectoral DTI breast reconstruction after nipple-sparing (NSM), skin-sparing (SSM), or skin-reducing mastectomy (SRM) between August 2018 and June 2025 (1663 mastectomies). Patients with prior radiotherapy were excluded. Intraoperative flap thickness was categorized as Group 1 (5-6 mm), Group 2 (7-9 mm), and Group 3 (>= 10 mm). The primary endpoint were early postoperative complications (<30 days), classified as major or minor. Results: Overall, 152 mastectomies (9.14%) developed early complications. Complication rates were comparable across flap-thickness groups (Group 1: 10.48%, Group 2: 9.57%, Group 3: 8.66%; p = 0.704). Rates of wound dehiscence, infection, implant extrusion, and minor complications did not significantly differ among the groups. Ischemic complications requiring revision were more frequent in thinner flaps (2.1% in Group 1 vs. 0.51% and 0.43% in Groups 2 and 3), although absolute numbers remained low. Periprosthetic seromas showed a statistically significant but clinically modest difference. Conclusions: Flap thickness alone is not an independent predictor of early morbidity in prepectoral DTI reconstruction. When intraoperative perfusion is adequate and a standardized protocol is used, even flaps <1 cm can be safely subjected to DTI prepectoral reconstruction. These findings support expanding prepectoral indications to selected patients with thin mastectomy flaps.