Serial tumour blood-flow measurements in androgen-dependent and -independent Shionogi tumour models.

Abstract

To investigate the relationship between blood supply and hormonal status of hormone-dependent and -independent tumours in mice. Contrast-enhanced dynamic magnetic resonance imaging (MRI) was used to measure tumour blood flow (TBF) in Shionogi tumours implanted subcutaneously in mice. Serial measurements were taken throughout the initial tumour growth period, and during regression and subsequent androgen-independent (AI) relapse of the tumours in male mice, and throughout the growth of AI tumours in female mice. Average TBF values and coefficients of variation were calculated from tumour tissue perfusion maps reconstructed from MRI data. The Tukey-Kramer test was used to identify differences between androgen-dependent (AD), male AI and female AI tumours. The mean TBF strongly depended on tumour size in all three stages of the tumour growth cycle. AI tumours had a significantly higher TBF than AD tumours, with mean (sd) values of 0.8 (0.3) (male AI) and 0.27 (0.1) mL/g/min (AD), (P < 0.001), and 0.61 (0.31) (female AI) and 0.27 (0.1) mL/g/min (AD) (P < 0.01), respectively. Tumour tissue perfusion was more homogenous in AI than in AD tumours, with a coefficient of variation of 0.91 (0.31) in male AI and 1.89 (0.48) in AD tumours (P < 0.001), and 1.47 (0.38) in female AI and 1.89 (0.48) in AD tumours (P < 0.05). AI Shionogi tumours have a higher TBF than AD tumours; this could have implications in the diagnosis, prognosis, therapy and monitoring of hormone-sensitive tumours.