Using [¹⁵O]-water pet it is possible to estimate tumour vascular physiological parameters including blood flow and the volume of distribution of water. My project investigated the way in which vascular physiology could be modified by anticancer treatments of (1) cytostatic and (2) cytotoxic nature. This thesis reports a series of studies using positron emission tomography (pet) and water labelled with radioactive oxygen-15. I also report some results with the tracers [¹⁵O]-carbon monoxide, [¹¹c]-thymidine and [11c]-bicarbonate. In practice, the studies revealed unanticipated potential for error in the methods used. Therefore this thesis has focused in large part on quality assurance of [¹⁵O]-water pet methods as used by the clinician researcher.EThOS - Electronic Theses Online ServiceGBUnited Kingdo