The Effect of Irradiating a Transplanted Murine Lymphosarcoma on the Subsequent Development of Metastases

Mice were implanted with a lymphosarcoma on either the thorax or leg. Some of these tumours were given a single dose of 240 kV x-rays on reaching a predetermined size, whilst others were left unirradiated. Metastases developed in specific lymph nodes, depending on the position of the transplanted tumour, and were larger if the tumour had been irradiated than if not. The growth rate of metastases in the ipsilateral axillary lymph node was faster than that of the transplanted tumours, irrespective of the radiation dose the tumour had received.