115IN - Addressing clinical challenges in targeted therapies with advanced imaging

Date 29 September 2012
Event ESMO Congress 2012
Session ESMO-EANM-ESR Joint symposium: Imaging biomarkers in the era of targeted therapies
Topics Cytotoxic agents
Staging procedures (clinical staging)
Basic Principles in the Management and Treatment (of cancer)
Imaging
Therapy
Biological therapy
Presenter Wim J.G Oyen
Authors W.J.G. Oyen
  • Department Of Nuclear Medicine, Radboud University Nijmegen Medical Centre, 6500 HB - Nijmegen/NL

Abstract

Advanced imaging techniques are being developed to provide information relevant for patient management beyond changes in tumor size. Treatment with novel targeted therapies showed that conventional RECIST measurements are insufficient to assess response as changes in tumor size occur relatively late, if at all. It has been shown that molecular imaging techniques provide predictive and prognostic information at baseline or by comparing baseline scans to scans obtained very early after the start of treatment. It aims at the (very) early identification of responders before tumor shrinkage occurs, but also indicating a high likelihood of relapse even before tumor growth is apparent. Furthermore, molecular imaging with radiopharmaceuticals may aid in identifying receptor overexpression or pathway activation in tumors before treatment with targeted therapies is initiated. The ability of FDG-PET to predict response of metastatic GIST to imatinib became the role model for the potential of molecular imaging to provide clinically relevant answers within days after the start of treatment. Since the introduction of integrated PET/CT the acceptance of the technology enormously increased. A large number of PET/CT studies was performed in patients treated with various targeted therapies (both antibodies and TKIs) in a wide variety of tumor types with both FDG and other radiopharmaceuticals such as FLT, a marker of proliferation. Similary, advanced CT (perfusion) and MRI (dynamic MRI, DWI, MRS) techniques have taken advantage of the development of technology. Following the introduction of therapeutic monoclonal antibodies such as bevacuzimab and trastuzumab, studies with the radiolabeled derivatives have been used to image the tumor-associated factors and receptors, targeted by these antibodies (immunoPET and immunoSPECT). It has been shown that this approach could successful visualize the antibody targets. More recently, small molecules (e.g. paclitaxel, lapatinib) have been radiolabeled and used in clinical studies. Following the numerous proof of principle and translational research studies, the time has come time to develop the role of the advances towards evidence-based imaging in clinical practice by systematically positioning advanced imaging for treatment selection in clinical trials.

Disclosure

The author has declared no conflicts of interest.