SIU 2017: Routine Use of Adjuvant Radiation After Radical Prostatectomy for Positive Surgical Margin: Not for All!

Lisbon, Portugal (  Dr. Dall’era gave a very interesting talk elaborating why not all patients with positive surgical margins (PSM) after radical prostatectomy (RP) should receive adjuvant radiation therapy. He began his talk with several important arguments why adjuvant treatment is nor for all. First, not all men with PSM recur, not all PSM are the same, early salvage may be just as good, significant cost of adjuvant radiotherapy, and the argument that novel imaging and biomarkers will help identify men at risk, who should be treated.

Dr. Dall’era mentioned the 3 prospective randomized trials assessing adjuvant radiotherapy after RP. These include the SWOG 87-94, EORTC 22911, and ARO 96-02. According to Dr. Dall’era, 30-35% of men in the SWOG and EORTC trials had persistent PSA after RP, making the treatment of radiation fall under the category of salvage and not adjuvant. Furthermore, only the ARO 96-02 required undetectable PSA at enrollment. Additionally, a substantial number of men in the control arm of these trials never recurred. Only the SWOG trial showed an overall survival advantage for adjuvant radiotherapy, and lastly, the patients in the control arms of all these trials generally received salvage radiotherapy later on.

Dr. Dall’era continued and stated that these 3 randomized trials don’t answer the question of whether all men with PSM need adjuvant radiotherapy. Some retrospective data show that up to 45% of men with PSM will not recur in a follow-up time of more than 10 years. Recent evidence also demonstrates that after 20 years of follow-up, no difference was seen in distant metastasis and overall survival in patients with PSM that received adjuvant radiotherapy, compared to those who didn’t. There is a difference in the types of PSM, and it is also known that Gleason score of 4 and above at the margin has a much more substantial risk of prostate cancer specific mortality than lower Gleason scores.

A description on the Decipher genomic classifier test was also given, as a possible way to mark those patients at risk for recurrence, which should be treated with adjuvant radiotherapy. Additionally, the usage of ultrasensitive PSA could be enlisted to help use decide who needs to be treated. Almost 100% of men with any postoperative ultra-sensitive PSA over 0.03 had eventual clinical biochemical recurrence (BCR).

Dr. Dall’era concluded his elaborate presentation by summarizing these points: Not all men with PSM recur, not all men with BCR progress to clinical recurrences or death. According to Dr. Dall’era, it is important to adopt a risk stratified approach and take into account the grade and length of PSM, the value of ultrasensitive PSA at 3 months postoperatively, measure time to PSA recurrence, and use novel biomarkers and imaging to improve care and choose the appropriate patients for adjuvant radiotherapy. Lastly, it is important to note, that early salvage radiotherapy may work just as well with less overtreatment.

Presented by: Marc Dall’era

Written by: Hanan Goldberg, MD, Urologic Oncology Fellow (SUO), University of Toronto, Princess Margaret Cancer Centre.Twitter: @GoldbergHanan at the 37th Congress of Société Internationale d’Urologie - October 19-22, 2017- Lisbon, Portugal