FIG. 10.

The effects of tumor type and size on oxygenation and blood volume. Median tumor pO₂ and the percentage of hypoxic region were estimated from EPRI in (A) SCCVII and (B) HT29 tumors. Representative pO₂ maps at three tumor sizes are shown in the left upper panels. Tumor pO₂ values from at least three tumors at each size are shown in red bar graphs (n = 3–4). The hypoxic volume, the percentage of the tumor volume having pO₂ <10 mmHg, was plotted as a line superimposed on the bar graphs (n = 3–4). Blood volume images (right panels) were obtained from MRI studies using USPIO (n = 3–4). MRI, magnetic resonance imaging; USPIO, ultrasmall superparamagnetic iron oxide particles. *p < 0.05. **p < 0.01. Adapted from Ref. (66) with permission. To see this illustration in color, the reader is referred to the web version of this article at www.liebertpub.com/ars