The VX2 carcinoma in the rabbit auricle as an experimental model for intra-arterial embolization of head and neck squamous cell carcinoma with dextran microspheres

Abstract

A head and neck cancer model is developed using the VX2 carcinoma cell line injected s.c. in both ears of New Zealand White (NZW) rabbits. The study is focused on the effects of intra-arterial embolization of the carcinomas with a new type of dextran hydrogel microspheres. During the phase of exponential growth the tumour-surface doubling-time was 7.1 ± 2.0 days. Standard deviation in growth of the tumours was significantly larger between separate animals than between tumours growing in the left and right auricle of each individual animal (2.0 versus 0.65 days). A fresh cell suspension containing at least 10.106 vital tumour cells was necessary to yield a tumour-take of 85%. The caudal auricular artery perfuses the caudal half of the external ear and is very suitable for macroscopic cannulation. Histological evaluation shows, that the use of dextran hydrogel micro spheres of at least 25 μm in combination with ligation of non-tumour perfusing branches of the central auricular artery yields diffuse embolization of the VX2 carcinoma. This tumour model can be of use in further studies to optimize particle size and dosage for embolization as well as to evaluate the effect of different anti-neoplastic drugs, slowly released by controlled degradation of dextran microspheres.