Fractional antedating goal response
Leyton and colleagues assessed the response of radiation-induced fibrosarcomas to cisplatin in mice .Using immunohistochemistry for proliferating cell nuclear antigen, decreased FLT uptake was correlated with decreased cell proliferation seen pathologically prior to evidence of change in tumor size measured grossly with calipers. assessed the ability of changes in the FLT PET/CT signals performed before and following one cycle of neoadjuvant chemotherapy to predict pathological response assessed after a second cycle of neoadjuvant chemotherapy in breast cancer patients .This method relies on changes in tumor size, which is likely a crude surrogate for alterations in tumor proliferation or cell death, which may occur much sooner than tumor shrinkage.
Written, informed consent was obtained from all patients and the trial was registered on with the identifier NCT00963807.Currently, The NCCN (National Comprehensive Cancer Network) Guidelines recommend induction (neoadjuvant) chemotherapy for patients with stage II or IIIA disease, though the appropriate role for neoadjuvant chemotherapy is still evolving .In this study, 354 patients with stages IB–IIIA NSCLC were randomized to receive induction chemotherapy versus no induction chemotherapy.One attempt to ascertain the biology of lesions seen on CT imaging has been with positron emission tomography (PET). FDG PET carries with it challenges in assessing response, notably uptake of the radiotracer into non-malignant inflammatory cells, which can confound assessments of tumor response.In addition, “flare” reactions and “stunning” of FDG activity levels by treatment have been described, which make it less than perfect in some instances as a general early metric of tumor response to treatment.