In 2017, a 25-year-old woman presented to our clinic with a giant circumferential nevus extending from the elbow joint to the shoulder. The nevus was about 31 cm long and 22.5 cm wide, covering 90% of the entire circumference of the upper arm (Fig. 1). Moreover, the lesion accounted for approximately 5% of the total body surface area. The giant nevus was present on the left upper extremity at birth, when it measured 21×15 cm, and at the age of 6 years, the patient underwent partial surgical removal of the nevus at the forearm and elbow with a full-thickness skin graft measuring 4.5×19 cm.

The patient preferred a procedure that would yield optimal results both functionally and aesthetically with minimal disruption to her daily life. We explained that a large flap was required to fully cover the lesion on the upper arm, but the larger the tissue expander, the longer the scar on the donor site, which can be prominent during the expansion period. For these reasons, we scheduled pre-expanded pedicled TDAP flap surgery on the patient’s left back and staged excision of the lesion through serial re-expansion of the transferred flap on the upper arm. Additionally, we believed that multiple rounds of general endotracheal anesthesia (GEA) would burden the patient; accordingly, we planned to use GEA for the main procedures and conscious sedation for the additional operations.

The operation focused on ensuring free functional movement of the arm, achieving the aesthetic goal of minimal scarring and skin tone matching, and allowing the patient to continue her typical daily activities and wear her usual clothing. Accordingly, we planned to perform sequential TE by combining pre-expansion of a pedicled TDAP flap at the donor site with multiple expansions of the transferred flap on the upper arm. We used a relatively small expander to limit the scarring of the donor site and to allow the patient to maintain her everyday routine, even though this increased the number of procedures necessary. The surgical process is summarized in Table 1.

Before surgery, the perforator arteries were detected using Doppler ultrasound and marked. With the patient under GEA and in the lateral decubitus position, an incision was made 2 cm anterior to the anterior border of the latissimus dorsi (Fig. 2A). Subsequently, we dissected through the suprafascial layer and found the perforators marked previously. Once the perforators were located, the pedicle dissection was continued through the intramuscular descending branch via the thoracodorsal artery. The serratus vessels and transverse branches were ligated. After isolation of the pedicle, we created a suprafascial pocket for the tissue expander (rectangular, 19×8×5 cm, 760 mL; Sebbin, Boissy-l’Aillerie, France). The bleeding was controlled and the area irrigated, and an expander was placed under the skin flap and perforator pedicle; the expander was then partially inflated (Fig. 2B). Starting 2 weeks after surgery, weekly serial expansions were performed until the expander reached maximal expansion volume. The tissue expander was gradually inflated to a total volume of 840 mL over 5 weeks.

Twelve weeks after completion of the expansion, a second operation was performed under GEA (Fig. 3). An incision was made along the previous operative scar, and dissection was carried out to expose the tissue expander. With the removal of the expander, we extended the incision and elongated the pedicle until it was long enough for the flap to be transferred without tension or kinking. The muscle around the pedicle was partially included to avoid vessel damage, and the fibrous capsule of the pre-expanded flap was partially excised. After harvest of the pre-expanded pedicled TDAP flap, we excised the nevus at the posterior region of the upper arm and at the elbow, and we covered the defect with the harvested flap. A new tissue expander (rectangular, 16×7×5 cm, 560 mL; Sebbin) was placed under the transferred TDAP flap for serial expansion. The donor site was closed primarily without skin tension. Starting 2 weeks after surgery, weekly serial expansions were performed until maximal expansion volume was reached.

Other procedures to remove the rest of the nevus were performed a minimum of 3 weeks after completion of the expansion. This and subsequent procedures (in other words, the third procedure and onward) were performed as day surgery in the outpatient department with the patient under local anesthesia and conscious sedation using propofol (Dongkook Pharm, Seoul, Korea) with secure monitoring of vital signs. After deflation of the expander, the remainder of the nevus was removed with as much flap coverage as possible without tension, and the re-expanded transferred flap was advanced to the area of the defect. During surgery, the expander was removed, and capsulotomy and capsulectomy were performed to allow maximal mobility of the expanded flap. After two additional rounds of serial expansion and excision, the nevus was removed completely. Eventually, through one round of expansion at the donor site and three rounds of transferred flap expansions, we covered the entire lesion of the upper arm with the pre-expanded, serially re-expanded pedicled TDAP flap. The average amount of inflation was 580 mL for the transferred flap. In the histopathological examination, no evidence of malignancy was found in the specimen. At 2-month and 1-year follow-up after the last operation, the patient showed a full range of motion with respect to the elbow joint and shoulder with no contracture, as well as healthy skin at the area covered by the flap. There were no complications, such as lymphedema, that sometimes occur during the removal of circumferential nevi (Fig. 4).