Video: Castrate Resistant, Non-Metastatic Prostate Cancer (M0 state) | Prostate Cancer Staging Guide
Prostate Cancer Staging Guide | Transcription
Hi, I'm Dr. Scholz. Let's talk about prostate cancer.
We're in the middle of a series about prostate cancer staging. At the PCRI we have a Staging Guide and we're loosely following the format in here. In this video, we're going to cover "Low-Royal." We have five different stages of prostate cancer, each subdivided into three subtypes: Low, Basic, and High. Today's video is about Low-Royal. Low-Royal is an advanced—Royal is the most advanced stage—so, Low-Royal is an advanced stage of prostate cancer. And Low-Royal is defined as a man who was Indigo, who's been on hormone therapy (Lupron for example) for usually many years, but now even with a low testosterone, the PSA is starting to rise.
Just for review, Basic and High-Royal are men that have scans showing cancer outside the pelvic region, in the bones. Basic-Royal: Five or fewer metastases. High-Royal: Six or more metastases. So Low-Royal is without metastases except for perhaps some enlarged lymph nodes in the pelvic region. It's defined as Royal because of the resistance to Lupron and it's other cousins such as Eligard and Firmagon, Zolodex and the like. Resistance to the best available therapy, which is hormone therapy, is a very serious development with prostate cancer, and that is why this category qualifies as Royal and not one of the earlier stages. Untreated men go on to develop metastases in the bones after about an average of 18 months. This is a very serious development and the advent of metastases needs to be prevented with appropriate therapy.
Historically, there's been no treatment for this category and doctors have often reassured their patients that it's okay to have a rising PSA and not take any immediate action. That, of course, is a big mistake. Why would people think that it's okay? Well, many men have been in remission for as long as 10 or more years and nothing's happened. Fears related to cancer have been dissipated. But the rising PSA with a low testosterone is a signal that things are changing quickly and something must be done. So what can be done? It turns out that modern, second-generation hormonal therapy such as Xtandi, Erleada, and there is a new medicine coming out called Darolutamide can delay the onset of metastases for about two years. That's a healthy amount of time considering that these medicines have relatively few side effects beyond what the Lupron is already causing. The studies have been done that show this delay in the onset of metastases with these medications are very high-quality studies, randomized prospective trials. What's interesting though is that at the research centers where these studies were done, the men had fairly high PSA levels, even though their scans were clear, the average PSA was in the 8-10 range. Men can be detected with Lupron resistance with much lower PSAs—less than 1, easily. Men who get on treatment earlier do even better. So if we can get an average two-year delay in metastases with someone starting with a PSA of 8-10 there's probably going to be much longer remissions in men that start earlier. In our own practice, we've seen men go on medicines with PSAs less than 1, and some of them have remained in remission for years and years, and there's no sign of them progressing at all.
So, it's clearly important to identify this sub-category of Low-Royal and get on the right treatment. When you hear doctors talking about Low-Royal, the common terminology is "M0." M0 means "M" for metastases, "0" means no visible metastases in the bones. So it's important to remember that even though scans are all clear, we're talking about a very serious stage of prostate cancer. Men who don't get treatment in a timely fashion are going to develop bone metastases in an average of 18 months. This can be prevented with modern new agents. Men who have rising PSAs who are on Lupron need to start treatment as quickly as possible.