Oncology Scan—Biology

Abstract

What has been termed the “Holy Grail” in radiation therapy research is the ability to use 1 or more biological assays to predict the likely outcome of radiation therapy treatment. This field of predictive assays has focused on 3 biological aspects of tumor response to fractionated irradiation: intrinsic radiosensitivity (functionally measured by clonogenic assay at 2 Gy, or SF2), potential doubling time or Tpot (measuring repopulation), and hypoxia. Each of these 3 aspects is measurable in human tumors, and each promises to provide a separation of tumors of similar stage into the good and the poor responders.