Patients who show biochemical recurrence of prostate cancer often go through treatments that can produce significant adverse events.
Gerald L. Andriole, MD, and co-authors recently presented a study at the 2021 Society of Urologic Oncology Annual Meeting that investigates the novel imaging modality 18F-Fluciclovine PET scan for patients with biochemically recurrent prostate cancer.1 This new technology is designed to identify specific areas of disease recurrence and in so doing allows targeted therapy to sites of recurrence thus avoiding more extensive, unnecessary treatment. Andriole is a Robert Killian Royce distinguished professor of urologic surgery at the Washington University School of Medicine in St. Louis, Missouri.
The clinical dilemma that the practitioners and patients faced when they had been treated for prostate cancer with either a radical prostatectomy or with radiation therapy [was that] if there was biochemical evidence of recurrence of the disease, until we had this PET scan, there was no way of knowing where or what the sites of recurrence were. And so, practitioners often made their best guess using clinical information, like how rapidly the PSA was rising or what the pathology was at the time of the radical prostatectomy. They often defaulted to a more aggressive treatment than was really necessary. Sometimes, they actually administered the wrong treatments. Now that we have the PET scanning with the fluciclovine, [for most] men who have biochemical recurrence (ie, those patients whose [prostate-specifc antigen] is rising after surgery or radiation therapy for prostate cancer) we can identify the specific sites or sites of recurrence and thereby use more directed therapy that specifically targets the abnormal sites and spares the patient unnecessary therapy.
The first was that when practitioners declared their treatment plans without the knowledge of the PET scans, they changed their treatment plans for two thirds of the patients once the scan results were known. So, two thirds of the time, the treatment plan was modified once the information from the fluciclovine PET scan was made available.
The second thing that's very important is that for 40% of the patients in whom the original treatment plan included hormonal therapy,hormonal therapy was eliminatedwhen the fluciclovine PET scan results were made available. This is important for patients, as Hormonal therapy is often associated with pretty significant side effects for men, including hot flashes, cognitive effects, and the like. And, It's never really a curative treatment anyway, so it's really helpful for these 40% of men to totally avoid the side effects of this treatment when it wasn't even going to be beneficial for them.
We are planning to monitor the patients whose treatment plans were modified with the knowledge of the fluciclovine PET scan and determine how their clinical outcomes are in comparison to patients who weren't studied with the PET scan.
The take-home message [is] that men who experienc biochemical recurrence after radical prostatectomy or radiation therapy should undergo PET scanning so that they can have specific targeted treatments administered to the site or sites of recurrence, rather than [be treated] using the historical type of clinical parameters that we used in the past.
Just as background in this particular study, we used data that had accumulated from 2 separate studies—1 that was done in the United States, referred to as the LOCATE trial,2 and 1 that was done in the United Kingdom, referred to as the FALCON study.3 So, this is a very generalizable group of patients that we were able to analyze, making our conclusions more robust.
1. Andriole GL, Scarsbrook AF. Impact of 18F-Fluciclovine PET/CT on plans for ADT in patients with biochemical recurrence of prostate cancer; data analysis from two prospective clinical trials. Paper presented at: 2021 Society of Urologic Oncology Annual Meeting; December 1-3, 2021; Orlando, Florida. Poster #144
2. Andriole GL, Kostakoglu L, Chau A, et al. The impact of positron emission tomography with 18F-Fluciclovine on the treatment of biochemical recurrence of prostate cancer: Results from the LOCATE trial. J Urol. 2019;201(2):322-331. doi:10.1016/j.juro.2018.08.050
3. Scarsbrook AF, Bottomley D, Teoh EJ, et al. Effect of 18F-Fluciclovine positron emission tomography on the management of patients with recurrence of prostate cancer: Results from the FALCON trial. Int J Radiat Oncol Biol Phys. 2020;107(2):316-324. doi:10.1016/j.ijrobp.2020.01.050. Epub 202 Feb 14