Adjuvant radiation therapy immediately after surgery improved survival in men with prostate cancer and high-risk features, according to study results published in Journal or Clinical oncology.
“Three previous randomized trials published in 2020 concluded that early rescue radiation should be the new standard of care for all men after prostate cancer surgery. However, there was a lack of men with high-risk traits in those studies,” Anthony V. D’Amico, MD, doctorate, professor and chief of genitourinary radiation oncology at Dana-Farber/Brigham and Women’s Cancer Center, Healio told me. “As a result, we simulated a group of 26,000 men from the US and Germany to investigate whether adjuvant radiation therapy as opposed to early salvage could have a survival benefit in men with risky characteristics in surgery, which was not well treated in previous randomized trials.”
D’Amico and colleagues evaluated the effect of adjuvant versus early radiation therapy on all-cause mortality risk in 26,118 men (median age, 62 years) treated for pT2-4N0 or N1M0 prostate cancer between 1989 and 2016. All men received treatment across four institutions in the US and Germany.
The median follow-up was 8.6 years.
Researchers reported 2,104 deaths, of which 25.62% were associated with prostate cancer. A total of 2,424 men had a high risk of death despite surgery based on unfavorable pathology defined as pelvic lymph node positive (n = 933) or Gleason score of 8 to 10 prostate cancer and disease extending beyond the prostate. Of this group, 428 received adjuvant radiation therapy, 1031 received early radiation and 965 received no radiation.
Results of a sensitivity analysis excluding men with persistent PSA showed that adjuvant radiation therapy was associated with significantly lower all-cause mortality compared to early radiation therapy in men with unfavorable pathology at radical prostatectomy when men with positive pelvic lymph nodes were included (adjusted HR = 0.66; 95% CI, 0.44-0.99) or excluded (aHR = 0.33; 95% CI, 0.13-0.85).
At 10-year follow-up after surgery, all-cause mortality was only 5% among men who received adjuvant radiation therapy, compared to 22% among those who received early radiation therapy.
These data indicate that the risk of death was reduced by a third in men treated with adjuvant radiation therapy who had prostate cancer that spread to lymph nodes, D’Amico said.
Anthony V. D’Amico
“We observed a 67% reduction in mortality and 20% improvement in 10-year survival with adjuvant versus early radiation therapy in the cohort of men with either positive pelvic lymph nodes or evidence of additional capsular elongation or seminal vesicle invasion in the context of Gleason scoring 8 to 10 prostate cancer,” said D’Amico.
A limitation of the study was that this is a retrospective study and there may be factors that have not been controlled for, D’Amico added.
“However, the analysis we performed was robust because it adapted to everything that was known,” he said. “Future research will delve more deeply into men with positive nodes to see whether adjuvant as opposed to early salvage benefits men with one positive node versus two or more positive nodes. There is controversy as to whether a single positive node provides adjuvant radiation. But based on our findings, we found an association, regardless of the number of positive nodes, with regard to a survival benefit for adjuvant as opposed to early rescue radiation.”
For more information:
Anthony V. D’Amico, MD, doctorate, can be reached at Brigham and Women’s Hospital and Dana Farber Cancer Institute, 75 Francis St., Boston, MA 02115; email: email@example.com.
🎬📺 Free Movies and Free TV Shows! 🎭🎬