On May 27th, 2016, the US Food and Drug Administration (FDA) issued a press release detailing the diagnostic benefits of a new radioactive agent used as an injection — Axumin. Axumin injections have been approved for diagnostic imaging in suspected recurrent prostate cancer in men.
A radioactive diagnostic agent, Axumin, has been approved for use in positron emission tomography (PET) imaging scans in men suspected with prostate cancer recurrence.
The approval of the radioactive agent will allow radiologists to employ it in the detection of prostate-specific antigen (PSA) in patients who have undergone the primary treatment of prostate cancer but still have elevated levels of PSA. Elevated levels of PSA are an indicator, though not definitively, of prostate cancer.
Safety Check Of This Agent
To check the safety and efficacy of Axumin, two studies were conducted. The first study comprised of a comparison between the 105 scans in men with suspected recurrences of prostate cancer, with the histopathology reports of prostate biopsy and biopsies of suspicious imaged lesions.
The second study assessed the agreement between the 96 Axumin and C11 choline scans in patients with median PSA values of 1.44ng/ml. In both cases, qualified radiologists studied scans to interpret the results.
The results of these two independent studies were coherent with both studies thus reinforcing the safety and efficacy of the drug and solidifying the proposal that the agent can be used for imaging prostate cancer in men with high PSA levels.
Prostate Cancer Stats
According to the Centers for Disease Control and Prevention (CDC), prostate cancer is the second leading cause of cancer death among men, with lung cancer being the chief reason.
According to the 2012 statistical data on prostate cancer, about 177,489 men in the US are currently living with prostate cancer and about 27,244 men have died of it.
Among other risk factors, high PSA levels in men after primary treatment indicate the chances of recurrence of prostate cancer.
PSA is a special protein made by the prostate gland. After the primary treatment, if the levels of PSA are still high, there is a probability that a person could develop prostate cancer again but it is not the case every time.
There is no set value for the normal PSA level but it has been seen that some men with PSA levels below 4.0ng/ml develop prostate cancer and that many men with higher levels do not level develop it. There are many other factors associated with the fluctuation in PSA levels in men such as urinary tract infection or prostatitis and hereditary nature.
Director of the Division of Medical Imaging products, Libero Marzella, said that those conventional imaging tests were unable to detect the actual location of the recurrent prostate cancer. However, Axumin provided an accurate alternative advancement in the field.
About Axumin Injections
Axumin, or fluciclovine F18, is a synthetic amino acid and can be actively transported to the prostate cancerous cells via amino acid transporters without being metabolized in the body or incorporated in the surrounding cells. It acts as a radiotracer and emits radiations during the PET scan which gives us subsequent relative information.
There is another radiotracer [18F] flouro 2-deoxyglucose that is used in PET scans but because of its intake and high urinary excretion problem, it cannot be used for imaging prostate cancer.
Minor Risks Associated With This Drug
Since Axumin is a radioactive element, it should be handled with maximum safety and protection to lessen the chances of exposure to the patients as well as the handlers. So far the only adverse reaction associated with this agent that has come under consideration is the redness and pain at the injection site as well as a metallic taste in the mouth.
Limitations Of Axumin Pet Imaging
It is mentioned in the study that there are minimal chances of image interpretation errors occurring with Axumin PET imaging. False image interpretation might lead to an overdiagnosis or underdiagnosis of the disease.
In reference to the study, a false positive image leads to overdiagnosis of the symptoms of the disease. On the other hand, a false negative report undermines the fact that the disease exists in the subject and the patient receives incomplete or no treatment for the disease. Additionally, a negative image does not ensure 100% protection against the recurrence of prostate cancer and vice versa.