To study vascular anastomosis patterns of internal mammary vessels (IMAV) as recipient vessels in deep inferior epigastric artery perforator (DIEP) flap breast reconstruction and evaluate clinical outcomes.

Early stage breast cancer patients receiving modified radical surgery with either immediate DIEP flap breast reconstruction or delayed DIEP breast reconstruction in the Department of Oncoplastic Plastic Surgery , Hunan Cancer Hospital from September, 2015 to January, 2019 were retrospectively analyzed. Unilateral pedicled DIEP flap was used in all cases with Zone Ⅳ discarded. IMAV were chosen as sole recipient vessels. According to the anatomy of flap pedicle and IMAV, the corresponding anastomosis patterns were selected, including: (1) two ends method. (2) one proximal end method. (3) two proximal ends method. (4) proximal trunk and its branch method. (5) distal end method. (6) proximal end to side method. Flap survival, breast morphology, recurrence of breast cancer, donor site wound healing were followed up. Descriptive methods were used for statistical analysis.

Two hundred and eight breast cancer patients were enrolled. The average age was 38.7±3.5 years (27-65 years). One hundred and nine cases received immediate breast reconstruction and 99 received delayed breast reconstruction. The average weight of flap was 410 g (295 - 640 g). The flap length was 23.9±0.8 cm. The width was 12.2±0.5 cm. The thickness of flap was 4.3±0.4 cm. The length of pedicle was 10.9±0.3 cm.One hundred and ninty-four DIEP flaps had two accompanying veins and 14 had one accompanying vein. One hundred and seventy-three cases had one internal mammary vein and 35 had two internal mammary veins. Vascular anastomosis patterns: Method 1 was used in 89 cases, method 2 in 49 cases, method 3 in 35 cases, method 4 in 25 cases, method 5 in 7 cases and method 6 in 3 cases. Among 208 flaps two failed. One flap using method 1 had vascular pedicle torsion and the other using method 2 had venous thrombosis. One case received secondary implant reconstruction following debridement and the other had recipient site was closed primarily. All the other 206 flaps survived completely without contracture deformation. The reconstructed breasts had good shape and elasticity. Linear scar was left on the donor sites. The abdominal wall function was not affected. All patients were followed up for 12-48 months (22.6 months on average) with satisfactory results. One case had brain metastasis and received further treatment. No local recurrence was found.

According to the specific anatomy of the vascular pedicle of DIEP flap and the internal mammary vessels, the vascular anastomosis method was selected flexibly to ensure breast reconstruction safety with satisfactory results.

Surgical flaps; Internal mammary vessel; Arteriovenous anastomosis; Deep inferior epigastric artery perforator flap; Breast reconstruction