ObjectivesLarge breast tumor resection can cause chest wall defects that are difficult to close. A combination of oncoplastic techniques is required to repair chest wall defects and immediately reconstruct the breast. In this report, we present the use of the contralateral internal mammary artery perforator (IMAP) flap to repair large chest wall defects and perform breast reconstruction for a series of patients.MethodsBetween July 2013 and June 2020, 10 patients and 4 patients underwent chest wall defect repair and breast reconstruction, respectively, with contralateral IMAP flaps. The average body mass index was 26.9 kg/m2 (range: 21.5–33.7 kg/m2). Tumor sizes varied from 2.5 × 1.5 × 0.8 to 9.5 × 6.0 × 4.0 cm3. Defect sizes ranged from 16 × 10 to 8 × 4 cm2. All patients underwent multiple imaging examinations to exclude abnormalities. Primary outcomes included complete tumor resection and flap survival. Secondary outcomes included the BREAST‐Q results and bilateral breast symmetry measurements.ResultsAll flaps exhibited good postoperative survival and were between 20 × 12 and 10 × 5 cm2. Two patients experienced minor complications that did not influence outcomes. No obvious donor site complications were observed. The BREAST‐Q results indicated favorable reconstructive efficacy, with “satisfaction with breasts,” “physical well‐being (chest),” and “satisfaction with the outcome” scores of 77.8 (range: 58–87), 83.2 (range: 77–89), and 80.1 (range: 70–88), respectively. No signs of tumor recurrence were observed during a median follow‐up period of 53.5 months (range: 6–83 months). However, poor postoperative bilateral breast symmetry was observed (vertical extent: 0.63 [range: 0.36–0.88]; horizontal extent: 0.64 [range: 0.41–0.80]).ConclusionsIMAP flaps are reliable options for chest wall defect repair and breast reconstruction for selected patients with locally advanced breast cancer and inner breast tumors. Despite poor postoperative bilateral breast symmetry, most patients reported excellent outcomes.