Which Approach is Best for Biopsy Gleason Score 9–10 Prostate Cancer?

Treatment with radical prostatectomy (RP) plus adjuvant external beam radiotherapy (EBRT), androgen deprivation therapy (ADT), or both (MaxRP) provides equivalent survival outcomes as EBRT, brachytherapy, and ADT (MaxRT) in men with Gleason score 9–10 prostate cancer, according to a new study published in JAMA Oncology.

“It makes logical sense that in these very aggressive prostate cancers, you need a multi-modality approach,” said study author Anthony V. D’Amico, MD, PhD, who is chief of the Division of Genitourinary Radiation Oncology and an institute physician at Dana-Farber Cancer Institute at Brigham and Women’s Hospital in Boston.

Researchers evaluated a total of 639 men (mean age, 65.83 years) with clinical T1–T4, N0M0 biopsy Gleason score 9–10 prostate cancer. In this cohort, 80 were consecutively treated with MaxRT between February 6, 1992 and April 26, 2013. A total of 559 men were consecutively treated with RP and pelvic lymph node dissection. Among the 559 men managed with RP and pelvic lymph node dissection, 88 received adjuvant EBRT (15.7%), 49 received ADT (8.8%), and 50 received both (8.9%). The median follow-up was 5.51 years among 80 men treated with MaxRT, and 4.78 years among 559 men treated with RP-containing treatments.

During the follow-up period, 161 men died; of these deaths, 106 were from prostate cancer (65.8%). There was no significant difference in the risks of prostate cancer–specific mortality (adjusted hazard ratio [HR], 1.33) and all-cause mortality (adjusted HR, 0.80) in men who underwent MaxRP vs those who underwent MaxRT. When comparing the two groups, the plausibility indexes for equivalence was 76.75% for the end point of the risk of prostate cancer–specific mortality, and 77.97% for the end point of the risk of all-cause mortality. Plausibility indexes for all other treatment comparisons were less than 63%.

D’Amico said this study should serve as a wake-up call that clinicians should be treating patients who have a Gleason score of 9–10 and other adverse features upfront with a multi-modality approach. “Waiting for the PSA to rise is not as good as treating upfront,” D’Amico said in an interview with Cancer Network. “A lot of men with this cancer are going unaddressed for a long time.”

Amar U. Kishan, MD, who is an assistant professor in the Department of Radiation Oncology at the David Geffen School of Medicine at the University of California in Los Angeles, said these findings are similar to those of a larger study he and his colleagues conducted. Kishan’s research compared outcomes between patients with Gleason score 9–10 disease treated with RP and EBRT plus brachytherapy.

“I think this is a good study,” Kishan told Cancer Network. “The conclusion regarding the importance of multimodality therapy is clearly an important one, and one that I agree with.”