Growth of xenografted head and neck cancer in nude mice pre-treated with whole body irradiation.

In an attempt to enhance the primary acceptance rate of human squamous cell carcinoma of the head and neck (HNSCC), nude mice (BALB/c) were given whole body irradiation (WBI) prior to heterotransplantation of tumour specimens. A total of 27 fresh HNSCC biopsies were transplanted, with a take rate of 15%. No difference in primary tumour acceptance rate was found between irradiated and non-irradiated mice. Only one of the accepted tumours established growth both in irradiated and non-irradiated mice. In a second experiment, three previously established tumour lines of HNSCC were re-transplanted to irradiated and non-irradiated mice. As compared with non-irradiated mice, the growth rate was lower in all tumours transplanted to irradiated mice, the difference being statistically significant in two out of the three tumour lines. The results of the study show that attempted immunosuppression by WBI of nude mice prior to tumour implantation does not improve the growth conditions of HNSCC. These findings further emphasise the complexity of the transplantation barrier against human tumour xenografts in nude mice.