When something could save lives, having an abundance of it on hand is a good thing. On the other hand, if there’s a scarcity of it, it won’t be readily available when it’s needed—and many lives will be put at risk. This is true for a prostate cancer (PCa) imaging agent called Gallium-68 (68Ga or GA 68 PSMA-11).
The great news about 68Ga is that on Dec. 1, 2020, the FDA approved its use for patients with suspected prostate cancer metastasis (when cancer cells spread from the place where they first formed to another part of the body) who are potentially curable by surgery or radiation therapy. The not-so-great news is that it has not been widely available.
What is Gallium-68?
Ga 68 PSMA-11 is a radioactive diagnostic agent that is administered in the form of an intravenous injection. As it circulates through the blood, it is formulated to adhere to a protein called PSMA on the surface of PCa cells anywhere in the body. Its form of radioactivity, which occurs in small, brief amounts considered harmless, emits subatomic particles called positrons that are detected by positron emission tomography/computed tomography (PET/CT scan). Even tiny locations of PCa spread in the bones or soft tissue will “light up.” The ability to locate these areas means appropriate treatment decisions can be made to intervene early and control the spread.
The problem is that 68Ga does not occur in nature. It is a manufactured isotope produced in a generator from a chemical element called germanium (atomic number 32). Germanium itself is not as abundant as other elements. It is mined in numerous countries and generally used as a semiconductor. However, it can be created in a cyclotron, and several years ago some manufacturers anticipated an increase in demand for germanium while was being researched for use in nuclear medicine.[i] These companies wisely began developing portable generators so that hospitals could produce 68Ga on site.
While that’s a great way to increase availability, there’s a geographic problem. 68Ga has a short half-life, meaning its usefulness quickly deteriorates—in 68 minutes, to be precise. Unless a PCa patient can come to a center that has such a generator, it’s not possible to produce the isotope in the hospital’s lab, run it down the hall, tackle the maze of sidewalks to the parking decks, hop in a car, and deliver it to an appropriately equipped community imaging center a few hours away to perform the scan. In short, the availability of 68Ga PSMA PET/CT scans has been restricted to centers that invested in cyclotrons.
New imaging kit facilitates wider availability
Great news was announced on Dec. 20, 2021—just over a year since the FDA approved 68Ga. The FDA has now approved a special 68Ga PET/CT imaging kit that improves access to this potentially life extending isotope. The kit, with the brand name illuccix, is made by a company called Telix. In their news release, the company explains, “Illuccix can be prepared with 68Ga via either GE’s FASTlabTIM cyclotrons or in nuclear pharmacies and healthcare centers across the country… This optionality, along with a four-hour shelf life after radiolabeling with 68Ga, enables Illuccix to flexibly extend the reach of advanced PSMA-PET imaging to patients across the country.”[ii]
It’s only been 12 months since 68Ga was FDA-approved, and already it’s becoming more widely available. The pace of imaging research and development, with rapid integration of Artificial Intelligence tools, is bringing benefits to patients that decades ago would have sounded like science fiction. The quest to conquer cancer and other diseases is clearly on a roll.
NOTE: This content is solely for purposes of information and does not substitute for diagnostic or medical advice. Talk to your doctor if you are experiencing pelvic pain, or have any other health concerns or questions of a personal medical nature.
References
[i] Massat MB. Nuclear Medicine Prepares for Greater 68Ba Demand. Appl Radiol. 2021;50(2):30-31.
[ii] Broderick J, Kahl K. “FDA Approves Novel PSMA-PET Imaging Product for Prostate Cancer.” Urology Times, Dec. 20, 2021. https://www.urologytimes.com/view/fda-approves-novel-psma-pet-imaging-product-for-prostate-cancer
About Dr. Dan Sperling
Dan Sperling, MD, DABR, is a board certified radiologist who is globally recognized as a leader in multiparametric MRI for the detection and diagnosis of a range of disease conditions. As Medical Director of the Sperling Prostate Center, Sperling Medical Group and Sperling Neurosurgery Associates, he and his team are on the leading edge of significant change in medical practice. He is the co-author of the new patient book Redefining Prostate Cancer, and is a contributing author on over 25 published studies. For more information, contact the Sperling Prostate Center.
