Tumour oxygenation levels correlate with dynamic contrast-enhanced magnetic resonance imaging parameters in carcinoma of the cervix

Background and purpose: The Eppendorf pO 2 histograph is the ‘gold standard’ method for measuring tumour oxygenation. The method is not suitable for widespread application because its use is limited to accessible tumours. A non-invasive imaging technique would be an attractive alternative. Therefore, the relationships between tumour oxygenation and dynamic contrast-enhanced magnetic resonance imaging (MRI) parameters were investigated. Materials and methods: The study comprised 30 patients with carcinoma of the cervix. Tumour oxygenation was measured pre-treatment as median pO 2 and the proportion of values less than 5 mmHg (HP5) using a pO 2 histograph. Repeat measurements were obtained for nine patients following 40–45 Gy external beam radiotherapy giving a total of 39 measurements. Dynamic contrast-enhanced MRI using gadolinium was performed prior to obtaining the oxygenation data. Time/signal intensity curves were generated to obtain two standard parameters: maximum enhancement over baseline (SI−I) and the rate of enhancement (SI−I/s). Results: Using the 39 measurements, there was a significant correlation between SI−I and both median pO 2 ( r=0.59; P