Abstract: Objective: To access the efficacy of slow Mohs micrographic surgery combined with latissimus dorsi myocutaneous flap in the treatment of giant dermatofibrosarcoma protuberans of the upper trunk. Methods: The two patients with protuberant dermatofibrosarcoma treated with slow Mohs micrographic surgery combined with latissimus dorsi myocutaneous flap Were retrospectively analyzed. Results: Both patients achieved negative pathological margins after the first-stage slow Mohs surgery. The postoperative wounds were 10 cm×13 cm and 15 cm×15 cm, respectively. Both were treated with secondary design of latissimus dorsi myocutaneous flaps to repair the primary defects, and the secondary defects were sutured directly. Both patients' flaps survived completely, and the wounds healed primarily. Conclusions: Slow Mohs micrographic surgery is a first-line choice for the treatment of dermatofibrosarcoma, and the latissimus dorsi myocutaneous flap can be used to repair large wound surfaces on the trunk after tumor resection.

Key words: dermatofibrosarcoma protuberans, Mohs micrographic surgery, latissimus dorsi myocutaneous flap