ASCO and Cancer Care Ontario update guideline on radiation therapy for prostate cancer

The American Society of Clinical Oncology (ASCO) and Cancer Care Ontario today issued a joint clinical practice guideline update on brachytherapy (internal radiation) for patients with prostate cancer. The update provides evidence-based recommendations for different patient risk groups, and specifies the most effective forms of brachytherapy.

"This guideline provides very clear direction about what is now the non-surgical standard of care for the majority of patients with prostate cancer - brachytherapy either by itself or as part of a combination approach," said Andrew Loblaw, MD, FRCPC, MSc, co-chair the Expert Panel that developed the guideline update, representing ASCO. "Brachytherapy is also more convenient than external beam radiation and has a much higher chance of curing the disease. However, not every patient should have brachytherapy and not all treatment centers are experienced in delivering high quality brachytherapy."

The guideline recommendations pertain to men newly diagnosed with prostate cancer who require or choose active treatment and are not considering, or are not suitable, for active surveillance. Patients may be ineligible for brachytherapy if they have moderate to severe urinary symptoms, an enlarged prostate, prior prostate surgery, and contraindications to radiation treatment, or are in poor physical health.

"For the urologists, who are most often the gate-keepers in terms of first contact with men with prostate cancer, this guideline update provides new information which they can incorporate into patient counseling and treatment decision-making," said Joseph Chin, MD ,FRCSC, co-chair the Expert Panel that developed the guideline update, representing Cancer Care Ontario. "By optimizing treatment selection, which may or may not be brachytherapy for a particular patient, outcomes should ultimately be improved."

Key recommendations of the guideline update:

• For eligible patients with low-risk prostate cancer either low dose rate brachytherapy (LDR) alone, external beam radiotherapy (EBRT) alone, or radical prostatectomy should be offered.
• For eligible patients with low-intermediate risk prostate cancer (Gleason 7, PSA < 10 ng/ml or Gleason 6, PSA 10-20 ng/ml) LDR brachytherapy alone may be offered.
• For eligible patients with intermediate-risk prostate cancer who choose to receive EBRT with or without androgen deprivation therapy (ADT), addition of a LDR or high-dose rate (HDR) brachytherapy boost should be offered.
• For eligible patients with high-risk prostate cancer receiving EBRT and ADT, brachytherapy boost (LDR or HDR) should be offered.
• Iodine-125 and Palladium-103 are each reasonable isotope options for patients receiving LDR brachytherapy; no recommendation can be made for or against using Cesium-131 or HDR monotherapy.
• Patients should be counseled about all their care options (surgery, EBRT, brachytherapy, active surveillance, as applicable) in a balanced, objective manner preferably from multiple disciplines.
• If choosing brachytherapy, a patient should go to a treatment center following strict quality assurance standards.

To develop this guideline update, an Expert Panel reviewed relevant literature published between 2011 and December 2016. Five randomized controlled clinical trials provided the evidence base for this guideline update. The Brachytherapy for Patients with Prostate Cancer: American Society of Clinical Oncology/Cancer Care Ontario Joint Guideline Update was published today in the Journal of Clinical Oncology.