The use of stereotactic radiotherapy in patients with metastatic prostate cancer.

This study examined stereotactic body radiotherapy (SBRT) as a treatment for advanced prostate cancer. This study concluded that SBRT may be effective in the treatment of these patients.

Oligometastatic prostate cancer is cancer that is no longer confined to the prostate gland. However, it has not yet become wide-spread to surrounding organs. It is usually treatable with curative therapy. This can include prostate surgery or radiation therapy. One form of oligometastatic cancer is oligoprogressive castration-resistant prostate cancer (oligo-CRPC). CRPC is cancer no longer responding to hormone therapy. Hormone therapy targets male sex hormones that fuel tumor growth.

Tumor-directed stereotactic body radiotherapy (SBRT) uses radiation beams from different directions. This means that the tumor receives high levels of radiation. The surrounding tissues receive low levels of radiation, with minimal damage. The impact of SBRT in the treatment of oligo-CRPC is still under investigation.

The records of 86 patients who received SBRT for oligo-CRPC were assessed in this study. The average length of follow up was 30.7 months.

The average length of time patients survived after SBRT without metastases (spread tumors) was 12.3 months. 52.3% of patients were alive one year after treatment, without the disease progressing. 33.7% of patients were alive two years after treatment, without progression of the disease. 

26 patients received a second course of SBRT. This was due to progressive disease. The average length of time patients survived without receiving whole body treatment was 21.8 months. 72.1% of patients survived for one year without requiring whole body treatment. 

Side effects on the bladder, sexual, and bowel functions were experienced by 3 patients overall.

This study concluded SBRT may be effective in the treatment of oligo-CRPC.

This was a small study which looked at the medical records of patients. New larger studies which actively follow patients, and do not rely on medical records are required.