BACKGROUND
Oral squamous cell carcinoma (OSCC) is the most common malignant tumor in the head and neck. A free flap is often used to repair tissue defects left after surgery. Due to the existence of 2 surgical sites—the donor site and recipient site—cross-contamination should be prevented during the operation. This report presents a case of donor tumor implantation suspected to be caused by cross-contamination.
CASE REPORT
A 57-year-old Chinese man was admitted with a mass in the left floor of the mouth, first noticed 2 months before. The biopsy confirmed squamous cell carcinoma (SCC). Under general anesthesia, extended resection of the left floor of the mouth SCC and repair with a left anterolateral thigh free flap were performed. Five months after surgery, a mass was found in the scar on the left thigh. Extensive resection of the left thigh mass was performed, and postoperative pathology revealed metastatic SCC. At the same time, a tumor was found on the right back and another on the chest wall. These 2 tumors were resected at the same time and were also confirmed as SCC. Seven months after surgery, the patient gradually developed local recurrence and systemic multiple metastases, and he died 10 months after surgery.
CONCLUSIONS
The “no tumor left behind” principle should be strictly followed in malignant tumor surgery to avoid malignant tumor implantation. Oral and maxillofacial surgeons should be aware of this and use appropriate techniques to avoid such incidents.

Keywords: Carcinoma, Squamous Cell; Implants, Experimental; Metastasectomy; Surgery, Oral