AUA, ASTRO amend guideline for adjuvant and salvage RT after RP

New high-quality and long-term evidence supports using hormone therapy with salvage radiation therapy after radical prostatectomy, according to a recent amendment to the American Society for Radiation Oncology (ASTRO) and AUA joint clinical guideline on adjuvant and salvage radiotherapy after prostatectomy.

“In the past, we would defer on the use of hormonal therapy in combination with radiation therapy,” said Guideline Panel Co-chair Richard Valicenti, MD, MA, of the University of California, Davis. “The data now shows that we should be offering hormonal therapy, or androgen deprivation therapy, with radiation when these patients are progressing after a radical prostatectomy. That’s the main message of the updated evidence-based guideline.”

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The guideline amendment was published in Practical Radiation Oncology (2019; 9:208-13). The authors reviewed 294 studies published from January 1990 to December 2012 in the original document, incorporating data from articles published between September 2012 and December 2017 in the amended version.

Data from three randomized controlled trials, including the ARO 96-02 trial (Eur Urol 2014; 66:243-50), provided 10-year data on the use of radiation therapy after radical prostatectomy. Only 5-year data were available from this trial when the original guideline was published, according to the amended guideline.

“We now know that radiotherapy and the combination of hormone therapy with radiation, following radical prostatectomy, have contributed to even more favorable outcomes for patients than seen previously,” Dr. Valicenti said in a press release. “With the current update, this collaborative guideline now reflects nearly three decades of multidisciplinary research.”

The amendment includes the recommendation that clinicians should inform patients with adverse pathologic findings including seminal vesicle invasion, positive surgical margins, and extraprostatic extension that, compared to radical prostatectomy only, adjuvant radiotherapy reduces risks of biochemical (PSA) recurrence, local recurrence, and clinical progression of cancer. Clinicians should also let patients know that the impact of adjuvant radiotherapy on subsequent metastases and overall survival is less clear, according to the amended guideline.

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The authors concluded two randomized controlled trials offered sufficient evidence to create a new statement. Guideline Statement 9 includes data from the RTOG 9601 (N Engl J Med 2017; 376:417-28) and GETUG-AFU 16 (Lancet Oncol 2016; 17:747-56) trials, both analyzing hormonal therapy’s effects on overall survival and on biochemical and clinical progression among patients who received salvage radiotherapy after prostatectomy. The trials offer strong evidence overall to support the use of hormonal therapy in those who are candidates for salvage radiotherapy. Clinicians offering the therapy should communicate its benefits and harms, according to the amended guideline.

The amended guideline also recommends more research on genomic classifiers that can predict treatment effectiveness.