New treatment therapies available for advanced prostate cancer

Prostate cancer remains the second leading cause of cancer death among men in the U.S. Largely because of a decrease in PSA testing, urologists across the country are seeing more patients with advanced and/or metastatic (spreading) disease. This usually makes the patient incurable.

Historically, patients who didn’t have success with primary treatment for their prostate cancer or who have developed metastatic disease have had very few options. Androgen (hormone) deprivation therapy (ADT) is started, drastically decreasing testosterone within the body.

Because prostate cancer cells require stimulation from testosterone to grow and divide, ADT causes regression of the cancer. Unfortunately if given enough time the cancer cells will mutate and, for a variety of reasons, will start to grow and spread again. This stage is defined as metastatic castrate resistant prostate cancer (mCRPC). The lack of further treatment options for this stage, other than chemotherapy, has served as a catalyst for the development and release of four new therapeutic options over the last five years.

Provenge (Sipuleucel-T) is a vaccine against prostate cancer and was approved by the FDA in 2010 based on three pivotal trials, each showing improvement in overall survival for patients with mCRPC.

In 2011 and 2012, the FDA approved two oral medications for mCRPC, Zytiga (Abiraterone Acetate) and Xtandi (Enzalutamide) . These oral medications are taken once daily, both showing dramatic improvements in overall survival. Initially these agents were only approved for patients that had already received chemotherapy. However, their results were so impressive that the FDA approved them for earlier use prior to chemotherapy.

Xofigo (Radium-223) was FDA approved in 2013 for certain patients with mCRPC and was found to improve overall survival and quality of life measures. A director at the FDA described it best while stating, “Xofigo binds with minerals in the bone to deliver radiation directly to bone tumors, limiting the damage to the surrounding normal tissues.”

This is a groundbreaking advancement since it has long been thought that when patients develop pain, progress and die of prostate cancer, it is due in part to the volume of cancer within the bones.

Given the rapid introduction of these novel therapies for advanced prostate cancer, understandably there is not yet a consensus on the correct sequence of the available therapies. There are multiple trials attempting to find the correct sequence and also determine if there is a benefit to getting some of these therapies sooner in the disease process, before the patient develops metastatic disease.

All of these therapies are available in Wichita, including Xofigo, which is currently delivered at the fastest growing Xofigo infusion center in the country. Furthermore, local physicians have been very active at enrolling patients in several trials for various urological cancers.

Wichita boasts one of the top enrolling centers in the country for a DNA test to help determine which prostate cancers need treatment vs. observation, and also has the leading enrolling center for a Xofigo trial following patients after the therapy is given. In addition, there are trials enrolling patients evaluating the benefits of earlier administration of Xtandi before the patient develops metastatic disease.

As knowledge is gained regarding the vast array of new treatment options for advanced prostate cancer, it is certain that recommendations and timing of these therapies will change. Physicians in Wichita treating advanced prostate cancer will continue to be at the forefront of this national discussion and maintain involvement in the trials forging our treatment guidelines.

This story was originally published July 18, 2015 at 5:36 PM with the headline "New treatment therapies available for advanced prostate cancer."