Anatomical research of pedicled lateral thoracic artery perforator flap in breast reconstruction after breast-conserving surgery

Objective To explore the anatomical basis of pedicled lateral thoracic artery perforator flap in breast reconstruction after breast-conserving surgery. Methods (1)To observe and record the resources and distribution of lateral thoracic artery in 8 adult specimens. Eight fresh adult cadavers(16 sides), 6 males, 2 females, aged from 28 to 71 years, 39.5 years on average. The specimens were perfused with red gel joining lead oxide via femoral artery. The occurrence rate, location, course, branch and vascular anastomosis of bilateral lateral thoracic arteries with peripheral blood vessels were dissected from the upper to the clavicle, the lower to the fifth rib, the outer to the axillary front, and the inner to the parasternum. The sources of the lateral thoracic perforator vessels were systematically classified. The outer diameter and pedicle length of the lateral thoracic artery were measured. (2) From August 2015 to February 2019, 12 cases of early breast cancer patients received breast-conserving surgery and pedicled lateral thoracic artery perforator flap transfer breast reconstruction in Hunan Province Cancer Hospital. All patients were female. Age ranged from 14 to 52 years old (43.2 years old on average). Eight cases were invasive ductal carcinoma and 4 cases were invasive lobular carcinoma. The locations of the masses were the upper lateral quadrant (n=9), the lower lateral quadrant (n=3). Survival of the flap and the shape of the reconstructed breast were observed after operation. Results Lateral thoracic artery was observed in 15/16 sides of 8 specimens, pierced between the pectoralis major muscle and latissimus dorsi muscle, outer diameter average of 0.80 mm(0.7-0.9 mm); pedicle length average of 8.15 cm (6.8-10.4cm), had rich vascular anastomosis with the thoracoacromial artery, internal mammary artery, thoracodorsal artery and intercostal artery. Lateral thoracic artery was classified in 6 types, originated from thoracoacromial artery (8/15, type Ⅰ), axillary artery (4/15, type Ⅱ), thoracodorsal artery (2/15, type Ⅲ), subscapular artery (1/15, type Ⅳ), multi-resources (1/15, type Ⅴ). In one specimen, lateral thoracic artery was absent (1/15, type Ⅵ). The average weight of the mass of tumor and breast tissue was 70-95(80.0±5.7)g. Size of the flaps were 10.5-13.5 (11.2±0.4) cm in length, 4.5-7.5 (6.3±0.5) cm in width, and 3.0-4.5(3.4±0.4) cm in thickness. Complications developed in 2 of the cases, fat necrosis in two and wound dehiscence in one, all healed smoothly with dressing treatment. All flaps survived. The reconstructed breasts' shape, texture and elasticity were good. There was no flap contracture deformation in all cases. Only linear scar left in the lateral thoracic donor sites. Function of shoulders were not affected. All 12 patients were followed up for 6 to 20 months (11.5 months on average) with satisfactory results. No recurrence of breast cancer happened. Conclusions The lateral thoracic artery perforator has variable resources, instant existence and extensive performance. The pedicled lateral thoracic artery perforator flap can be a useful, alternative and reliable technique in breast reconstruction after breast conserving surgery, especially in laterally located breast cancer. Key words: Breast neoplasms; Mammaplasty; Lateral thoracic artery; Perforator flap; Breast-conserving surgery