Exploring Cyberknife for Prostate Cancer

Cyberknife is an alternative option to treat prostate cancer, as well as many other cancers such as lung, brain, spine, liver and pancreatic cancer. It is not a surgical procedure, but a form of stereotactic body radiation therapy (SBRT) and robotic-assisted radiosurgery that utilizes a computerized robot to automatically deliver high doses of radiation to the prostate gland. For men with prostate cancer, Cyberknife is recommended for men with cancer limited to the prostate, and men with low to moderate risk prostate cancer.



Key statistics for prostate cancer:

·         Prostate cancer is the most common cancer among men, except for skin cancer.

·         Prostate cancer is the second leading cause of cancer death in men in the United States.

·         In 2014, an estimated 220,800 men in the United States will be diagnosed with prostate cancer.

·         About 93 percent of prostate cancers are found when the disease is confined to the prostate and nearby organs.

·         Overall, most men who develop prostate cancer (99%) are expected to live at least five years after diagnosis.

The advantages of Cyberknife include no hospitalization, low levels of toxicity produced, and less pain compared to other procedures. The disadvantages of Cyberknife include fatigue, erectile dysfunction (20 to 30 percent of patients develop erectile dysfunction), there is no doctor or surgeon controlling the device, a lack of high definition internal visuals to accurately diagnose and treat prostate cancer, it can be difficult to accurately stage the cancer, it requires multiple trips to the hospital for treatments, and it is a fairly new surgery which means there is limited clinical history to determine the true long-term effectiveness.

CyberKnife is most often used for patients with early stage prostate cancer confined to the prostate or in combination with another therapy, such as external beam radiation for patients with cancer that is present beyond the prostate. Your doctor will recommend a treatment plan depending on the stage of the patient’s prostate cancer. There have been a number of studies published on CyberKnife for prostate cancer. According to CyberKnife, studies have shown that ‘at five years after treatment a recurrence-free rate of 93 percent has been reported. Recurrence-free rates of 100 percent at 44 months, 97.5 percent at 51 months, and 94 percent at 4 years have also been reported. Toxicity has been quite low; rates of grade 2-3 toxicity at 20-60 months after treatment range from 2-10 percent for urinary toxicity and 0-5 percent for bowel toxicity. Erectile dysfunction has ranged from 60 percent at 35 months for an early experience to 13-40 percent at 1.5-3 years for more recent experiences in which the prostate gland is delineated with the aid of MRI, which typically reduces the volume of the region exposed to radiation.’