Prostate Ca: Equivalent efficacy for RP, radiation in high-risk patients?

Other key prostate cancer studies from AUA 2018 included updated survival data from the European Randomized Study of Screening for Prostate Cancer and a multi-center trial of MRI-targeted biopsy. The prostate cancer take-home messages were presented by Kelvin A. Moses, MD, PhD, of Vanderbilt University Medical Center, Nashville, TN.

• In a study of high-risk prostate cancer comparing treatment with radical prostatectomy versus radiation therapy and androgen deprivation, there were critical significant differences between the two populations, but Kaplan-Meier curves showed no difference in local failure, distant metastasis failure, and overall survival, indicating that there is likely equivalent efficacy between radical prostatectomy and radiation in this population.
• Updated survival data at 19-year follow-up from the European Randomized Study of Screening for Prostate Cancer showed a significant difference in progression to metastatic disease in men screened for prostate cancer versus controls. There is a significant increase in prostate cancer mortality in the control group, and the separation of curves begins at about 8 years from the time of screening.
• During active surveillance, use of the prostate health index (phi) and multiparametric MRI in combination is a more accurate predictor of grade reclassification at next surveillance biopsy than either test alone.
• Men on active surveillance for prostate cancer show moderate to high levels of anxiety early on, but their anxiety was relieved and improved significantly over time.
• Adverse pathology at radical prostatectomy was observed at a threefold higher rate for favorable intermediate-risk prostate cancer (based on several definitions) versus low-risk disease, a finding with important implications for counseling patients about their potential for disease progression while on surveillance.
• Follow-up and long-term results of studies of thermal and ultrasonic ablation, including their use as focal therapy, are still pending, but they are promising.
• In the management of oligometastatic disease, treatment of the primary tumor may have a survival benefit over systemic therapy alone. A randomized trial will be undertaken to study this subject.
• A test of the external validity of the Prostate Cancer Intervention versus Observation Trial (PIVOT) using reference cohorts from the SEER database, the National Cancer Database (NCDB), and PLCO trial showed that the PIVOT population was significantly less healthy than the NCDB and PLCO populations where Charlson data were available. Also, overall mortality was 64% in the PIVOT trial versus 8% to 23% in an equivalent population in the other series. PIVOT is thus likely not applicable to clinical practice.
• An examination of the impact of prior local therapy on overall survival in men who eventually reached metastatic castrate-resistant prostate cancer found that men who received radical prostatectomy plus or minus adjuvant or salvage radiation had significantly improved survival compared to those receiving radiation alone or observation or androgen deprivation. Treatment of the primary tumor does have long-term survival benefit in this high-risk group.
• In an expanded cohort of men with prostate cancer bone metastases, a mitochondrial DNA point mutation at 10398, over 50% of patients had a mutation at this location, which far exceeds any other somatic mutation previously reported, suggesting functional importance.
• A sub-analysis of SPARTAN trial data examining PSA progression in patients with non-metastatic castration-resistant prostate cancer taking apalutamide (ERLEADA) showed that a shorter PSA doubling time was associated with increased risk of metastasis or death, increased risk of symptomatic progression, and a shorter time to progression during treatment. 93% of patients receiving apalutamide had a significant >50% decline in PSA from baseline; PSA declined to <0.2 ng/mL in 40% of patients and <0.02 ng/mL in 13%. Median time to PSA response was less than 1 month.
• Early results of a randomized clinical trial of diet intervention in men on active surveillance did not show any significant differences in tissue specimens, but future data may have long-term implications.
• A multicenter trial found MRI-targeted biopsy to be non-inferior to standard transrectal ultrasound-guided biopsy for diagnosis of clinically significant prostate cancer.