Radiotherapy (Radiation) To The Primary Tumor Benefits Men With Prostate Cancer Who Have Distant Metastasis at Diagnosis

[JoelT]

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.

To find out if, in fact the 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

[Bluebird11]

Joel, thanks for this article. When first diagnosed in 2007, the theory was not to touch the prostate (diagnosed distant mets) because it was considered the 'mother' tumor. Once the local tumors in the prostate were no longer active- there would be a signaling to other spots in the body, and these in turn would want the need to grow.

This is why, I understood the prostate wasn't removed.

Does this make sense, the way I've described it?

So, now the discussion is this may not be the case?

Has anyone after being diagnosed with distant mets ever gone back years later to try to stop the localized PCa with radiation or other means?

When dealing with what we are dealing with, we have a localized problem that continues to need stabilizing, and then mets that need to be controlled. It's like two separate areas we are dealing with.

With mets to a vertebrae, they can radiate that vertebrae, but then there's the gland itself creating it's own problems.

Any new thinking other than some of the latest meds like xtandi, zytiga etc...

thanks..

genie

[JoelT in reply to Bluebird11]

Geneie,

Thinking changes and will continue to change. All we can do is go with the current thought and hope it is the best.

Down the near term road be prepared to hear more about genetic testing and PARP Inhibitors.

[Hidden]

My 2nd opinion urologist suggested no removal or radiation of the prostate if metastasis evidence found. That makes no sense to me. If the main prostate tumor is shedding cancer cells, which turn into mets, why wouldn't you attack the main tumor? I wouldn't think a study would even be needed to support that argument.

[JoelT]

There isn't agreement among Docs about the value of "debulking" tumors in cases like you have described. However, there is increasing study evidence that supports its positive value.

I suggest that you go to the Advanced Prostate Cancer Blog I write (www,advancedprostatecancer.net) and specifically to my very recent post speaking to this question (advancedprostatecancer.net/....

I also have a pod cast about debulking on iTunes (Prostate Cancer Pod Cast).

Also, look at my post in the beginning of this string.

Bottom Line - Thinking has moved strongly in the direction of the value of debulking.

If it were me I would treat the primary tumor(s).

Joel

[Cancersucks]

Ex did not receive radiation until this week, 16 months after diagnosis. He had hundreds of skeletal mets but his prostate showed no evidence of tumors via PET scan. He is also 44yo and ONC decided against prostatectomy or radiotherapy as pain was minimal and mets were widespread. Now, with unbearable pain to lumbar spine and left hip (femoral head fracture due to lesions), EBR was initiated with cabazitaxel although prognosis is poor.

Joel, what are your thoughts about radiotherapy at diagnosis if pain is nonexistent or minimal? There still are risks to this treatment as well... I have talked to men with bowel issues and/or colon cancer etc. due to radiation.

[JoelT]

The problem with external beam radiation(EBT) (beta radiation) when there is a large number of mets is both the practicality of radiating many different sites as well as the amount of radiation that would be required.

A better alternative is the drug Xofigo. It is a superior drug to treat bone mets. It is a radio pharmaceutical that emits alpha radiation. The drug mimics calcium that is attracted to bone, especially to bone that has a lot of metabolic activity (which prostate cancer mets have) and then as it enters the bone matrix it radiates the met. Being an alpha emitter it has limited effects on surrounding tissue.

EBT always comes with the potential of developing side effects including bowl and urinary issues. Targeting of radiation has improved greatly, but we still have way too many cases of off targeted radiation causing significant damage to good healthy tissue. The more radiation the more the risk of developing radiation induced problems.

Joel