This article regarding 68Ga DOTATATE Positron Emission Tomography (PET) comes to us from Mayo Clinic’s, Dr. Ayse T. Kendi and Medical/NET oncologist Dr. Thorvardur Halfdanarson, regarding this new diagnostic tool for imaging NETs. As this is now available at Mayo Clinic, Rochester, MN, I wanted you all to be aware of it.
68Ga DOTATATE Positron Emission Tomography (PET) is the new golden standard for imaging of neuroendocrine tumors (NETs). [68Ga] DOTATATE PET has been used in Europe and Australia for the last 10 years effectively as the first line imaging choice for NETs and replaced Octreoscan years ago. Recently this imaging modality has been approved by FDA and was made available to the NET community in USA. 68Ga DOTATATE has unique ability to bind to the somatostatin receptors that are overpopulated on the cell surface of NET cells. The somatostatin receptors can serve both as a target for imaging such as Ga68 DOTATATE PET/CT imaging and the less accurate Octreoscan as well as a target for therapy, either with somatostatin analogs (octreotide and lanreotide) and radioactively tagged somatostatin analogs such as Lu-177 DOTATATE (Lutathera). Gallium is the part that acts like a light-source that is attached to the peptide (DOTATATE) which has high affinity to bind to these receptors. Once the [68Ga] DOTATATE is injected through a vein and circulates in the body for about 60 minutes, it is time to get the images. Unlike Octreoscan, you don’t need to have multiple visits to nuclear medicine. One visit for about 2 hours is all that is needed.
68Ga DOTATATE can detect more and smaller lesions than the older Octreoscans, has lower radiation and is essential for assessment for peptide receptor radionuclide therapy (PRRT). With the advent of Ga68 imaging, there is no role for Octrescans where Ga68 imaging is available. Please know that although most of NETs will light up, some won’t light up and you may need another imaging with MRI, CT or FDG-PET/CT.
Please also note that, although it is FDA approved, it is an imaging modality that is not available in every hospital or imaging center. Please make sure to ask your NET oncologist if and where you could get the imaging.
At Mayo, we have completed more than 100 cases since November 2016. As a team we are very efficient both in acquisition and interpretation of the images. We work in close collaboration of NET oncologists in our institution and most, if not all patients will be offered the opportunity to meet with a NET specialist within then Division of Medical Oncology to discuss the results of the Ga68 DOTATATE imaging study and to formulate a treatment plan going forward which also will include the use of circulating blood markers as indicated. There are now data to suggest that treatment outcomes are better for patients treated at large and specialized NET centers.
Please feel free to comment or ask any questions that you may have. I will see that your questions are answered by one of our clinicians at Mayo.