A novel agent for imaging NETs

Nuclear Medicine Pilot Grant Announced

The Education and Research Foundation (ERF) for Nuclear Medicine and Molecular Imaging announced the winner of the 2017 Pilot Research Grant in Nuclear Medicine, a grant sponsored by the NET Research Foundation (NETRF).

Babak Behnam Azad, Ph.D., Johns Hopkins School of Medicine, won the one-year award for his innovative proposal, which is focused on development of “An improved approach for detection and therapeutic monitoring of neuroendocrine tumors (NETs) by PET.”

Diagnosing neuroendocrine tumors

Unlike other current advances in NET detection that rely heavily on imaging agents that interact with somatostatin receptors present on the surface of tumor cells, Dr. Azad plans to explore how amino acids and the proteins that transport them can be used to detect NETs earlier and non-invasively using positron emission tomography (PET). Dr. Azad explained that this different direction is critical for development of a more effective and reliable approach to detect a wider range of NET tumor types, monitor therapeutic response throughout the treatment cycle, and more accurately diagnose NETs in a broader range of patients.

Babak Behnam Azad, Ph.D.
The Johns Hopkins School of Medicine

“The thing that people don’t talk about enough I feel is that those receptors are not permanently there. Patients that undergo NET therapy; they are typically given somatostatin analogs which bind to receptors prior to the imaging. So once the patient actually undergoes that therapy that changes the cancer biology of the tumor. So that those receptors may no longer be there. So when you do the imaging on the somatostatin targeted imaging it looks like there is no tumor when in actuality there could still be a tumor, it just doesn’t have those receptors”

Earlier diagnosis of neuroendocrine tumors

Nuclear medicine scans use imaging agents or tracers to “bind to and light up” the area of interest.  Tumor cells consume large amounts of nutrients like amino acids to sustain their survival and fuel their rapid growth. Specific proteins, called transporters, shuttle amino acids to the cancer cells. So, a tracer that can specifically bind to these transporter proteins will help reveal areas with higher amino acid concentrations.

Dr. Azad plans to evaluate structural modifications of the existing investigational amino-acid tracer called Fluoro-L-DOPA. The structural changes he proposes will create a novel agent that is engineered to have increased stability and sensitivity for detection of NETs. Dr. Azad hopes those modifications will create a more enduring tracer that will produce sharper images needed to detect even the smallest tumors, regardless of whether those tumors express somatostatin receptors, leading to earlier and more accurate NET diagnosis.