Risk of lymph node metastases after en bloc cold steel, en bloc laser-, and piecemeal laser surgical resection of auricular VX2 carcinoma

There is some controversy in the literature if lymph vessels are enduring sealed during piecemeal CO₂ laser surgery of squamous cell carcinomas of the head and neck or a propagation of tumor cells into the lymphatics occurs. The aim of the present study was to analyze the incidence of lymph node and distant metastases after different methods of resection of a VX2 carcinoma in an animal model. A solid auricular VX2 carcinoma was induced in 200 rabbits. Seven days later, an en bloc cold steel (group A), en bloc laser surgical resection with CO₂ laser in continuous wave mode with 2 W (group B), or piecemeal laser surgical resection after transection of the tumor with CO₂ laser in continuous wave mode with 2 W (group C) or 20 W (group D) was performed. The animals were killed and the incidence of lymph node and distant metastases was compared between the different groups. Of the rabbits, 21.1 % developed lymph node metastases and 10 % pulmonary metastases. The incidence of lymph node metastases was 17.4 % in group A, 20.4 % in group B, 26 % in group C, and 20 % in group D. These differences were not statistically significant. En bloc cold steel, en bloc laser-, or piecemeal laser surgical resections include similar risk of postoperative metastases. Propagation of tumor cells cannot be excluded with certainty by any of these methods.