Lymph node metastasis in an animal model: effect of piecemeal laser surgical resection

BACKGROUND AND OBJECTIVES: Endoscopic laser surgical resection of advanced squamous cell carcinoma (SCC) often requires division of the tumor into several pieces. It is unknown if this approach influences the incidence of regional and distant metastases. STUDY DESIGN/MATERIALS AND METHODS: In 143 rabbits VX2 SCC was induced. Eight days later the tumor was resected by two different methods. In the first group en bloc cold steel resection was performed. In the second group piecemeal laser resection was performed. On the 51th day the animals were sacrificed and examined for lymph node and distant metastases. RESULTS: After piecemeal laser resection 47.7% of the animals had lymph node metastases compared to 24.6% after en bloc resection (P = 0.01). The incidence of distant metastases did not differ for the two groups. CONCLUSIONS: In our model narrow margin piecemeal laser resection was associated with a higher incidence of metastases compared to wide en bloc surgical resection. The exact mechanism responsible for this increase is unclear.