Objective To summarize the strategy and surgical procedure for unilateral breast reconstruction using a

combined bilateral lower abdominal flap and a unilateral free perforator flap from the deep femoral artery. Methods From December 2019 to October 2022， four patients with breast cancer underwent unilateral breast reconstruction using a combined bilateral lower abdominal flap and a unilateral free perforator flap from the deep femoral artery. The patients were aged 27 to 40 years， with a mean age of （32.4±2.3） years. All cases involved immediate breast reconstruction for early-stage breast cancer， and all patients underwent modified radical mastectomy. Lower abdominal flap designs included： transverse unilateral vascular pedicle （1 case）， transverse bilateral vascular pedicle （1 case）， transverse pedicled rectus abdominis muscle flap combined with a free lower abdominal flap （1 case）， and longitudinal bilateral vascular pedicle （1 case）. Directions of the deep femoral artery perforator flaps included： transverse thin thigh muscle flap （1 case）， transverse adductor magnus perforator flap （1 case）， vertical thin thigh muscle flap combined with adductor magnus perforator flap （1 case）， and oblique adductor magnus perforator flap （1 case）. All femoral flap vascular pedicles were anastomosed to the anterior serratus branch of the thoracodorsal vessels， with the second set of vascular pedicles anastomosed to the lateral thoracic artery and vein. All lower abdominal flap vascular pedicles were anastomosed to the proximal end of the intrathoracic  vessels， with the second set of vascular pedicles anastomosed to the distal end of the intrathoracic vessels. Results All flaps survived. The reconstructed breasts had acceptable contours and good elasticity， with no flap contracture or deformation. The donor site for the lower abdominal flap harvested longitudinally showed poor healing and was repaired using a Z-plasty； All other donor sites healed smoothly， leaving only linear scars， with no significant impact on lower abdominal or lower limb function. Follow-up ranged from 6 to 40 months （mean 19.4 months）. Breast contour was satisfactory， and no cases of breastcancer recurrence were observed. Conclusion The combination of bilateral lower abdominal flaps with a unilateral free perforator flap from the deep femoral artery is suitable for reconstructing a relatively large unilateral breast. Adequate preoperative preparation and the formulation of a clear surgical strategy are key to ensuring a safe and satisfactory outcome.

Breast cancer, Perforator flap from the femoral-deep artery, Lower abdominal flap, Breast reconstruction