The auricular VX2 carcinoma: feasibility of complete tumor resection.
The aim of the study was to test the feasibility of resection of VX2 auricular squamous cell carcinoma (SCC) in New Zealand White rabbits (NZW), its influence on the regional and distant metastases and the general prognosis. In 71 NZW rabbits, successful in sano wide margin resection of auricular VX2 SCC was performed 7 days after tumor induction. The animals were sacrificed and examined for metastases after 6 weeks. Local recurrences occured in 7% of the animals. In 28.2% lymph node (LN) and in 15.5% distant metastases developed. Regional metastases presented in 100% of the animals with recurrence and in 22.7% of the RO animals (p < 0.001). Distant metastases presented in 80% of the animals with local recurrence and in 10.6% of the R0 animals (p < 0.001). Of the animals with local control, those with N+ had a significantly higher incidence of distant metastases (46.7%) compared to those with N0 (0%, p < 0.001). Local control and LN involvement were found to be important prognostic factors for early tumor-related death. The VX2 auricular model resembles head and neck (HN) SCC in humans morphologically, pathophysiologically and as a complex neoplastic disease. In the experimental setting it behaved similarly to the clinical situation of wait-and-see in N0 HNSCC patients. Tumoral microemboli present a possible mechanism for the development of recurrences.