ObjectiveTo explore the effectiveness of the modified designed bilobed latissimus dorsi myocutaneous flap in chest wall reconstruction of locally advanced breast cancer (LABC) patients.MethodsBetween January 2016 and June 2019, 64 unilateral LABC patients were admitted. All patients were female with an average age of 41.3 years (range, 34-50 years). The disease duration ranged from 6 to 32 months (mean, 12.3 months). The diameter of primary tumor ranged from 4.8 to 14.2 cm (mean, 8.59 cm). The size of chest wall defect ranged from 16 cm×15 cm to 20 cm×20 cm after modified radical mastectomy/radical mastectomy. All defects were reconstructed with the modified designed bilobed latissimus dorsi myocutaneous flaps, including 34 cases with antegrade method and 30 cases with retrograde method. The size of skin paddle ranged from 13 cm×5 cm to 17 cm×6 cm. All the donor sites were closed directly.ResultsIn antegrade group, 2 flaps (5.8%, 2/34) showed partial necrosis; in retrograde group, 6 flaps (20%, 6/30) showed partial necrosis, 5 donor sites (16.7%, 5/30) showed partial necrosis; and all of them healed after dressing treatment. The other flaps survived successfully and incisions in donor sites healed by first intention. There was no significant difference in the incidence of partial necrosis between antegrade and retrograde groups (χ2=2.904, P=0.091). The difference in delayed healing rate of donor site between the two groups was significant (P=0.013). The patients were followed up 15-30 months, with an average of 23.1 months. The appearance and texture of the flaps were satisfactory, and only linear scar left in the donor site. No local recurrence was found in all patients. Four patients died of distant metastasis, including 2 cases of liver metastasis, 1 case of brain metastasis, and 1 case of lung metastasis. The average survival time was 22.6 months (range, 20-28 months).ConclusionThe modified designed bilobed latissimus dorsi myocutaneous flap can repair chest wall defect after LABC surgery. Antegrade design of the flap can ensure the blood supply of the flap and reduce the tension of the donor site, decrease the incidence of complications.