THE "NEW" PROSTATE CANCER INFOLINK

The publication of the ASCENDE-RT clinical trial (discussed here) has led to a revision in the brachytherapy guidelines (available here) issued jointly by the American Society of Clinical Oncology (ASCO) and Cancer Care Ontario (CCO). The guidelines are for patients who choose radical therapy rather than active surveillance.

ASCO and CCO based their guidelines only on data from randomized clinical trials that included brachytherapy as an option.  They exclude high-dose-rate brachytherapy (HDR-BT) as a monotherapy because it has not been proven in a randomized clinical trial.

The new guidelines suggesting which therapies are suitable are stratified by patient risk level:

• Low risk
  • Low-dose-rate brachytherapy (LDR-BT) alone
  • External beam radiation therapy (EBRT) alone, or
  • Radical prostatectomy (RP)
• Intermediate risk
  • For favorable intermediate risk-patients (no Gleason score> 3 + 4, no more than half the cores positive, PSA < 10, and clinical stage < T2b), LDR-BT alone
  • For other intermediate-risk patients, EBRT with or without androgen deprivation therapy (ADT) and a brachytherapy boost (LDR-BT or HDR-BT) to the prostate.
• High risk
  • EBRT and ADT and a brachytherapy boost (LDR-BT or HDR-BT)

The guidelines also include the following qualifying statements:

• Patients should be counseled about all their management options (surgery, EBRT, active surveillance, as applicable) in a balanced, objective manner, preferably from multiple disciplines.
• Recommendation for low-risk patients is unchanged from initial guideline, because no new randomized data informing this question have been presented or published since.
• Patients ineligible for brachytherapy may include: moderate to severe baseline urinary symptoms, large prostate volume, medically unfit, prior transurethral resection of the prostate, and contraindications to radiation treatment.
• ADT may be given in neoadjuvant, concurrent, and/or adjuvant settings at physician discretion. It is noted that neoadjuvant ADT may cytoreduce the prostate volume sufficiently to allow brachytherapy.
• There may be increased genitourinary toxicity compared with EBRT alone.
• Brachytherapy should be performed at a center following strict quality-assurance standards.
• It cannot be determined whether there is an overall or cause-specific survival advantage for brachytherapy compared with EBRT alone, because none of the trials were designed or powered to detect a meaningful difference in survival outcomes.

Neither the patient nor the doctor should take these to be their only options. ASCO/CCO only included options for which there is Level 1 evidence; that is, evidence from randomized comparative clinical trials. Patients, doctors, and insurance providers should make treatment decisions based on the full array of available clinical data, understanding that higher level evidence carries more weight.

Editorial note: This commentary was written by Allen Edel for The “New” Prostate Cancer InfoLink.

Filed under: Living with Prostate Cancer, Management, Treatment | Tagged: ASCO, brachytherapy, CCO, guideline, risk, Treatment |