Cell proliferation in human tumours measured by <i>in-vivo</i> labelling with bromodeoxyuridine

Abstract

The causes of failure after radiotherapy or chemotherapy may be related to physical or biological factors. The physical factors will include geographic miss in radiotherapy. The biological reasons may be inadequate drug delivery in chemotherapy or resistance of nutritionally deprived or hypoxic cells, a capacity to repair damage or rapid proliferation of the tumour cells so that repopulation may occur during treatment. There is much current interest in repopulation and it would be of value to identify those tumours which have rapid cell proliferation for, in these cases, a change in drug scheduling or shortening the overall treatment time with radiotherapy may lead to increased success by overcoming the effect of repopulation (Fowler, 1985). We have previously described a method for labelling proliferating cells in human tumours by measuring the uptake of bromodeoxyuridine (BrdUrd) into cells synthesizing DNA, following an intravenous injection, and the potential applications of this procedure to the measurement of proliferation rates in human tumours (Begg et al, 1985; Wilson et al, 1985). In this preliminary communication we report on three human tumours where kinetic studies have been performed and demonstrate the potential advantages of the technique.