ASCO20: Novel Imaging Modality Under Study in Biochemically Recurrent Prostate Cancer
Posted: Wednesday, June 10, 2020
Particularly in men with biochemically recurrent prostate cancer who have low PSA levels (< 2 ng/mL), current imaging modalities do not adequately localize and characterize occult disease. However, according to a prospective phase III trial, a novel diagnostic tool demonstrated its potential to do so—effectively enough, in fact, to clinically impact many physicians’ treatment plans. The CONDOR study focused on 18F-DCFPyL (also known as PyL), a second-generation fluorinated PSMA-targeted PET imaging agent. Michael J. Morris, MD, of Memorial Sloan Kettering Cancer Center, New York, and colleagues presented their findings during the ASCO20 Virtual Scientific Program (Abstract 5501).
A total of 208 enrolled men (median PSA level = 0.8 ng/mL) had rising PSA levels after definitive therapy. They also had negative or equivocal standard-of-care imaging (eg, CT/MRI, bone scintigraphy). The patients received a single injection of 9 mCi (333 MBq) ± 20% dose of PyL, followed by PET/CT 1 to 2 hours later.
Previously, the trial’s primary endpoint was met: “Correct localization rate, defined as percentage of patients with a 1:1 correspondence between at least one lesion identified by PyL-PET/CT and the composite standard of truth: pathology, correlative imaging, or PSA response,” the investigators recapped. Here, the secondary endpoint, impact of PyL-PET/CT on clinical patient management, was also shown to be met.
According to local radiology assessment, PSMA-avid lesion(s) were identified in 69.3% of patients. In fact, “63.9% had a change in intended management after PyL-PET/CT, of which 78.6% were attributable to positive PyL finding(s) and 21.4% to negative PyL scans.” These modifications included salvage local therapy changed to systemic therapy (n = 58); observation before initiating therapy (n = 49); noncurative systemic therapy changed to salvage local therapy (n = 43); and planned treatment changed to observation (n = 9). In addition, PyL was considered to be well tolerated.
Disclosure: The study authors’ disclosure information can be found at coi.asco.org.
