The use of needle biopsies for radiobiological assessment of oxygen levels in KHT-C tumors.

Hypoxia affects the sensitivity of cells to radiation. Hence there is considerable interest in the development and assessment of techniques for measuring oxygen levels. In the work described here, we explore the use of tumor needle biopsies (fine needle aspirates) in an assay that is standard in the field of radiation biology: the paired survival assay. We found that needle biopsies are a feasible option for estimating cell survival when conducting this assay, and that the variability in cell survival between tumors was greater than that between different biopsies from the same tumor. Using this technique, we then compared measurements of tumor hypoxia using the paired survival assay and the growth delay assay in the same individual tumors. We found a significant correlation between these two techniques.