Comparative measurement of regional blood flow, oxygen and glucose utilisation in soft tissue tumour of rabbit with positron imaging

C15O2 and 15O2 steady state techniques were used to measure regional blood flow (RBF) and regional oxygen utilisation (ROU) in a rabbit tumour model. RBF values were 4.6+-0.6 ml min/100 cc for normal muscle tissue and 11.0+-3.0 ml/min/100 cc for tumour surface. Corresponding values for ROU were 18.3+-3.5 μmol/min/100 cc for normal tissue and 39.7+-20.1 μmol/min/100 cc for tumour surface. 18F-2-fluoro-2-deoxy-D-glucose (2FDG) was used in the same model to measure glucose metabolic rate. The values obtained were 4.3+-2.1 μmol/min/100 cc for normal muscle and 53.8+-18.3 μmol/min/100 cc for tumour tissue. Tumour-to-muscle ratios increased more rapidly with time for 2FDG than for oxygen utilisation and blood flow. The effect of radiation on tumour and normal tissue was followed by measurements of RBF and ROU. RBF values increased both in tumour and normal muscle tissue during radiation and decreased during one week after radiation. ROU-values decreased (30%) in tumour and increased (45%) in normal muscle tissue during radiation. One week after radiation, ROU-values were 30% lower in tumour and 45% higher in normal muscle tissue. (U.K.)