Radiocurability of a transplantable murine sarcoma as influenced by immune competence of the host and adjuvant active specific immunotherapy.

The immunization induced in CBA mice by allogenic transplantation of sarcoma J was evaluated through the rejection rate of a subsequent isologous tumour graft. Female animals appear to be significantly much more competent at various stages of sarcoma growth as after their definite cure by radiation or surgery. A difference of response according to the sex is also present with regard to the auto-immune reaction evoked by tumour irradiation. A marked discrepancy in radiotherapy efficiency is linked to the disparity of immune behaviour, emphasizing the fact that an immunologically competent host constitutes an important factor of tumour radiocurability. In male recipients, an adjuvant active specific immunotherapy potentiates tumour response to a single dose of radiations. On the contrary, the adjunct treatment may display a detrimental effect in animals which already possess a high degree of anti-tumour immunization.