Effect of intratumoral heterogeneity in oxygenation status on FMISO PET, autoradiography, and electrode Po2 measurements in murine tumors

Conclusions:Ex vivo dual-tracer autoradiography documented the ability of in vivo FMISO PET to distinguish between confluent areas of either viable tissue or necrosis. Electrode Po2 measurements could not be ascribed to specific areas in the tumors. Less uptake of FMISO in SCCVII squamous-cell carcinoma than in C3H mammary carcinoma could be caused by scattered foci versus confluent areas of viable hypoxic tissue in the 2 tumors, respectively.