Local therapies improve survival in men with metastatic prostate cancer at diagnosis

This study investigated the benefit of local therapies as first-line interventions for metastatic prostate cancer. Authors reported improved survival with radiation and surgery among men with metastatic prostate cancer at diagnosis.

Metastatic prostate cancer is cancer that has spread to distant parts of the body. The first-line treatment for metastatic prostate cancer generally involves hormone therapy. Local treatments, such as surgery or radiation, are less commonly prescribed. However, there is evidence to suggest that treating the primary tumor site with local therapies can slow metastatic cancer progression and improve survival. Local therapies include different types of radiation therapy, such as external beam radiation therapy or brachytherapy, and prostate surgery. More high-quality studies are needed to establish the benefit of local treatments for metastatic prostate cancer. 

This study examined the records of 15,501 men with metastatic prostate cancer at diagnosis. Men were divided according to type of treatment received. 9.5% of men received local therapy. 90.5% of men received non-local therapy (hormone therapy, watchful waiting, or radiation to metastatic non-primary tumors). 66% of men receiving local therapy underwent hormone therapy (treatment to block male hormones, such as testosterone, involved in prostate cancer growth) within 6 months of diagnosis. Treatment outcomes were followed for an average of 39 months.

3-year overall survival rate (proportion who have not died from any cause since treatment) was 63% for the local therapy group. This was significantly higher compared to 48% in the non-local therapy group. A 3-year overall survival benefit was observed among men undergoing local therapy with hormone therapy (57%) compared to hormone therapy alone (48%). Brachytherapy was the local therapy associated with the highest 3-year overall survival (80%). This was followed by prostate surgery (78%) and external beam radiation therapy (60%).

Men undergoing local therapy had a 39% reduced overall mortality risk compared to men undergoing non-local therapy. Higher age, additional medical conditions, higher tumor stage, and extent of cancer spread each significantly increased mortality risk. Analysis showed that men with a predicted 3-year overall mortality risk of more than 70% do not benefit from local therapy.  

 Authors concluded that local therapies improved survival in men with metastatic prostate cancer at diagnosis. Men with a lower tumor risk and good general health showed the greatest survival benefit.