Pitfall in the Surgical Management of a Shrunken Skin Defect after Neoadjuvant Chemotherapy for Locally Advanced Breast Cancer

A 53-year-old woman with a large, easy-bleeding, and ulcerated breast tumor visited our hospital due to severe anemia. Transfusion and Mohs’ chemosurgery gave the patient marked improvement of her local and general condition. After confirming the human epidermal growth factor receptor type 2 (HER2)-positive breast cancer with no distant metastasis, anti-HER2 agents-containing chemotherapy brought about clinical complete response of the locally advanced breast cancer with a shrunken but still large skin defect. We, therefore, treated the patient with mastectomy and axillary node dissection but failed to directly close the skin even after full skin undermining. We then tried to cover the skin defect using a latissimus dorsi flap, that is, horizontal spindle skin 12 × 6 cm in size, but again failed to fully cover the skin defect. We finally and ostensibly covered the skin defect through an additional skin incision to the recipient skin, but could not get complete wound healing. Pathological study showed a marked collagen fiber around the skin defect and faint viable cancer cells beneath the nipple. The patient required 3 months of wound management for complete wound healing, leading to the application of anti-HER2 agents without anticancer agent to the patient during that time as an adjuvant therapy. Regrowth of her hair once lost by the neoadjuvant chemotherapy (NAC) made the patient refuse the adjuvant anthracycline-containing chemotherapy after wound healing. The patient, therefore, received trastuzumab-emtansine for a year and has been well for 17 months postoperatively. Breast surgeons should note that a skin defect after favorable response to NAC is often surrounded by less stretchable skin due to chemotherapy-induced massive collagen fiber and requires careful preoperative planning for skin closure.