Today, most PET oncology procedures are performed using the non-proprietary tracer FDG. FDG-PET captures increased tissue glucose metabolism, a hallmark of many tumors. However, FDG also has shortcomings, particularly in terms of specificity: FDG-PET cannot reliably distinguish malignant tissues from non-malignant proliferating tissues or from tissues with increased glucose metabolism being due to other stimuli such as infection, inflammation. In addition, while most tumors are FDG-avid, some are not. For example, FDG-PET is not suitable for differentiated tumors of the prostate, particularly because of their slow growth and low metabolic activity.
Our focus in Oncology imaging at Piramal Healthcare, is based on indications, where FDG has limitations. Our [Ga-68] labeled molecular imaging agent for the detection of localized prostate cancer, has successfully completed proof-of-mechanism studies in humans.
Exploiting adaptations of the tumor metabolism other than increased glucose consumption is an additional focus of research at Piramal Healthcare, Imaging Division. Our front-runner in this area is FSPG – a [F-18] labeled agent targeting the cystine/glutamate exchanger (system xC-). This compound also finished proof-of-mechanism studies in a variety of different tumor entities.
Images courtesy Prof. Moon, ASAN MC, Seoul, Korea; Prof. Gambhir, Stanford Univ., U.S.A