HOUSTON — In an unexpected turn of events, a team including investigators with the Naval Medical Center in Portsmouth, VA., found that adding short-term androgen deprivation therapy (STADT) to prostate bed salvage radiotherapy not only reduced progression in advanced prostate cancer but also improved patients’ mental processing speed.1
That was not true, however, in patients who had STADT combined with prostate bed radiotherapy (PBRT) and also pelvic lymph node radiotherapy (PLNRT), although they had the greatest decline in cancer progression.
Jeffrey Wefel, PhD, of MD Anderson Cancer Center in Houston presented the study highlights at the 2023 American Society of Clinical Oncology (ASCO) annual meeting in Chicago, June 2-6, 2023.
The study built on RTOP 0534, an international randomized phase 3 trial that published results in The Lancet last year. That study demonstrated that STADT benefitted men who had persistently detectable or prostate-specific antigen (PSA) scores that rose after being initially undetectable following prostatectomy. At a median of 8. 2 years of follow-up with survivors, the five-year freedom from progression rates were 70.9% for PBRT, 81.3% for PBRT plus STADT and 87.4% in the group that had PBRT, STADT and PLNRT.2
The team presenting at ASCO hypothesized that treatment with STADT would additionally lead to a greater decline in neurocognitive function when compared to PBRT alone. To test the hypothesis, they undertook longitudinal monitoring of neurocognitive function in 429 of the 1,716 men in RTOP 0534.
The team used the Clinical Trial Battery [Hopkins Verbal Learning Test – Revised (HVLT-R), Trail Making Test (TMT), and the Controlled Oral Word Association (COWA) test] at baseline, six weeks, one year and five years after the end of radiotherapy. When necessary, raw scores were adjusted to standardized z-scores to account for age and education.
Test completion was 82% at baseline, 76% at six weeks, 63% at one year and 30% at five years. Delayed The greater decline in neurocognitive function between the group with the PBRT alone and the group having all three treatments was as expected. Recall was seen in 16% of patients who received all three treatments, vs. 7% in the PBRT-only group (p=0.023). Patients who received all three therapies also had greater decline on the HVLT-R Total Recall and Delayed Recall.
The team did not anticipate that the comparison between the PBRT and PBRT plus STADT group would favor those who had STADT at six weeks, based on improvement on the Trail Making Test [1.498 (SE 0.626, p = 0.017), which measures processing speed.
“Compared to patients treated with PBRT alone, patients treated with PBRT+STADT+PLNRT exhibited greater worsening in episodic verbal learning and memory processes at six weeks after the end of RT, while patients treated with PBRT+STADT exhibited greater improvement in processing speed,” the researchers concluded. “The absence of long-term or progressive cognitive decline associated with STADT-containing regimens is promising but limited by substantial missing data at year 5.”
- Wefel JS, Karrison T, Pollack A, Baalogh AG, Watkins-Bruner D, Gomella LG, Michalski JM, Hallman MA, Rodrigues G, Seawaard SA, Kuettel MR, Barker JL, Camarata AS, Hopkins JO, Greenberg M, Jones J, Sandler HM, Seiferheld W, Movsas B. Neurocognitive function outcomes in NRG/RTOG 0534, the SPPORT trial. 2023 ASCO annual meeting. June 2-6, 2023. J Clin Oncol 41, 2023 (suppl 16; abstr 12022)
- Pollack A, Karrison TG, Balogh AG, Gomella LG, Low DA, Bruner DW, Wefel JS, Martin AG, Michalski JM, Angyalfi SJ, Lukka H, Faria SL, Rodrigues GB, Beauchemin MC, Lee RJ, Seaward SA, Allen AM, Monitto DC, Seiferheld W, Sartor O, Feng F, Sandler HM. The addition of androgen deprivation therapy and pelvic lymph node treatment to prostate bed salvage radiotherapy (NRG Oncology/RTOG 0534 SPPORT): an international, multicenter, randomized phase 3 trial. Lancet. 2022 May 14;399(10338):1886-1901. doi: 10.1016/S0140-6736(21)01790-6. PMID: 35569466; PMCID: PMC9819649.