The common belief is that if you are diagnosed with prostate cancer that has already developed metastases only a systemic treatment will provide a life extending benefit. In other cancers it has been shown that the treatment of the primary tumor improves survival (tumor debulking).
To find out if, in fact radiotherapy treatment of the primary tumor in prostate cancer with distant metastasis would provide a similar positive benefit, researchers evaluated the efficacy and toxicity of radiotherapy of the primary tumor in prostate cancer in men with metastasis.
The study included 140 men with metastatic prostate cancer at initial diagnosis. Metastatic sites were divided into 4 groups as follows: solitary bone, 2-4 bones, 5 or more bones, and visceral organs (soft tissue). The researchers compared the patient, tumor, treatment characteristics, and clinical outcomes between men treated with radiotherapy [PRT] group or without radiotherapy to the primary tumor.
The men in the PRT group were statistically significantly younger, however all of the other characteristics showed no difference.
The study found that the overall survival (OS) and biochemical failure-free survival (BCFFS) were improved in PRT men (3-year OS: 69% vs. 43%, p = 0. 004; 3-year BCFFS: 52% vs. 16%, p = 0. 002).
Multivariate analysis identified the PRT as a significant predictor of overall survival (hazard ratio [HR] = 0. 43, p = 0. 015). None of the men in the PRT group (38 men) experienced severe (grade 3 or higher) genitourinary or gastrointestinal toxicity.
This most interesting data suggests that radiotherapy to the primary tumor was associated with improved overall survival and BCFFS in metastatic prostate cancer.
The results of this study warrants additional controlled clinical trials of men diagnosed with stage IV prostate cancer. In the mean time, men who are diagnosed with metastatic disease, should discuss with their doctors the merits of having radiotherapy despite having distant Metastasis.
PloS one. 2016 Jan 25*** epublish ***
Yeona Cho, Jee Suk Chang, Koon Ho Rha, Sung Joon Hong, Young Deuk Choi, Won Sik Ham, Jun Won Kim, Jaeho Cho