New ASCO/CCO Guidelines for Metastatic Prostate Cancer

The American Society of Clinical Oncology (ASCO) and Cancer Care Ontario (CCO) have released a joint clinical practice guideline for treatment of men with metastatic castration-resistant prostate cancer (CRPC), which was published in the Journal of Clinical Oncology. According to the new guideline, androgen deprivation therapy (ADT) should be continued throughout the course of treatment and additional targeted therapies should be offered in conjunction with ADT. The guideline emphasizes patients’ quality of life on treatment and the consideration of the costs of therapy. It also stresses that palliative care should be offered to all metastatic CRPC patients.

“This guideline incorporates data for multiple newly available drugs for men with metastatic castrate-resistant prostate cancer,” Ethan Basch, MD, director of the cancer outcomes research program at the UNC Lineberger Comprehensive Cancer Center in Chapel Hill, North Carolina and co-chair of the ASCO/CCO expert panel, told Cancer Network. “The guideline considers efficacy, toxicity, quality of life, strength of evidence, and strength of panel recommendations for each drug.”

“Including quality of life data in the guideline helps people understand how the different treatments will make them feel,” said Andrew Loblaw, MD, co-chair of the genitourinary cancer disease site group for CCO and co-chair of the ASCO/CCO expert panel, in a statement. “We also have to be conscious of cost, because it can affect access to treatment and quality of life.”

“Metastatic prostate cancer commonly causes pain, physical debility, and decrements in overall quality of life. The panel feels it is important to consider quality of life and symptoms when discussing and choosing treatment with patients,” Basch added. “Drug developers should be measuring these outcomes rigorously in pre-approval clinical trials.”

With six new therapies for metastatic CRPC approved in the last few years, clinicians and their patients now have many treatment options to understand. The guideline is a way to facilitate an informed choice of the best potential therapy for each patient.

The guideline was created by a panel of prostate cancer experts who reviewed the medical literature up to June 2014. The panel reviewed the 28 randomized clinical trials from 1979 to 2004 that were part of the 2007 ASCO/CCO guideline, as well as an update from 2012 that included an additional 25 trials.

According to Dr. Basch, docetaxel is one of several options available for men with CRPC, though toxicity should be discussed. “The distinction between pre-docetaxel and post-docetaxel that has played a role in regulatory trials is not used in this guideline and is not felt to be useful for guiding clinical care. There is not sufficient information about combining or sequencing drugs to support any recommendations.”

Key summary of the guideline recommendations

1. ADT, either pharmaceutical or surgical, should be continued indefinitely.

2. Abiraterone with prednisone, enzalutamide, or radium-223 (for men with bone metastases) should be offered alongside ADT.

3. Docetaxel with prednisone should be offered, and cabazitaxel may be offered to those men who experience disease progression despite treatment with docetaxel. Side effects of these chemotherapies should be discussed.

4. Sipuleucel-T may be offered to men with few or no symptoms.

5. Ketoconazole or other antiandrogens, such as bicalutamide, flutamide, and nilutamide, may be offered, but clinicians should recognize that they have limited clinical benefit.

6. Bevacizumab, estramustine, or sunitinib should not be used as therapy for metastatic CRPC.

7. Palliative care should be an option for all patients alongside potentially effective therapies.