Posted: Monday, October 24, 2022
According to Michael Ng, MBBS (Hons), FRANZCR, of St. Vincent’s Hospital, Sydney, Australia, and colleagues, imaging with 18F-DCFPyL PET/CT, a novel prostate-specific membrane antigen (PSMA) tracer, resulted in a significant impact on management intent in patients with prostate cancer who were being considered for salvage radiotherapy, compared with standard CT imaging alone. These research findings, which were published in The Journal of Nuclear Medicine, revealed the new imaging tactics changed treatment plans for nearly 50% of patients.
“The group of patients studied—all post-surgery without other confounding treatments (no prior radiotherapy and no prior drug therapy) with a low and focused PSA range between 0.2 to 2.0 ng/mL—reflects a common management problem,” noted Dr. Ng in a press release from the Society of Nuclear Medicine & Molecular Imaging. “The study’s results are timely and applicable for patients experiencing their first recurrence after prostate surgery.”
The prospective study enrolled 100 patients who had a prior radical prostatectomy and a prostate-specific antigen (PSA) level of 0.2 to 2.0 ng/mL. Enrollees underwent diagnostic CT and 18F-DCFPyL PSMA PET/CT imaging, and treatment intent was recorded at baseline, after CT, and after PSMA imaging.
The investigators reported that PSMA PET/CT detected disease in 49.9% of patients, compared with 15.5% via diagnostic CT. Major changes in treatment intent occurred more frequently after PSMA imaging than after CT imaging (12.5% vs. 3.2%; P = .01), and this was true for moderate changes as well (31.3% vs. 13.7%; P = .001). Most commonly, additional treatment was advised; specifically, recommendations for elective pelvic radiation therapy increased from 15.6% after CT to 33.3% of patients after PSMA imaging. Similarly, recommendations for nodal boost and concurrent androgen-deprivation therapy increased from 0% to 22.9% and from 22.9% to 41.7% of patients, respectively. For 55 patients, follow-up data at 18 months revealed that 94.5% had a PSA level at or below 0.2 ng/mL, and 74.5% had a level that was undetectable (≤ 0.03 ng/mL).
Disclosure: For full disclosures of the study authors, visit jnm.snmjournals.org.