Blood flow distribution within transplantable tumours in the mouse.

Tumour blood flow was estimated by fractional distribution of rubidium in two allografts (B16 melanoma and Lewis lung tumour) and two xenografts (Glioma 522, a human grade IV astrocytoma and Mel-mo, a human melanoma), in order to investigate the influence of certain tumour characteristics on tumour perfusion. In all four tumours perfusion decreased with increase in tumour weight. The rubidium extraction in Mel-mo was markedly lower than that of the other three tumours; this tumour was the most necrotic. Necrosis was patchy in Glioma 522 and Mel-mo, but predominantly central in B16 and Lewis lung tumour. However, all tumour nodules examined showed a similar pattern of rubidium extraction: high at the rim with a rapid fall towards the centre. It appeared that while overall blood flow may be related to the extent of necrosis, blood flow distribution within tumour nodules did not correlate closely its pattern.