New tests for advanced and aggressive forms of prostate cancer

Recent media releases have provided initial information about new tests for “advanced”, BRCA mutation-associated and for “aggressive” forms of prostate cancer that need immediate intervention. However, we suspect that some further clarifications will be necessary before these tests become widely available.

One media release, from The Institute of Cancer Research in the UK, has announced the development and validation of a “three-in-one blood test” that can be used to:

  • Identify prostate cancer patients who are potentially good candidates for treatment with the growing class of PARP inhibitors (e.g., olaparib and others) because they have mutations to the BRCA1 or BRCA2 genes
  • Analyze patient DNA after PARP inhibitor treatment has been started, to see which patients were responding and which weren’t (so that patients who were not responding could be switched promptly to some other type of treatment)
  • Monitor responding patients over the course of treatment to watch for signs of genetic evolution and resistance to treatment.

The scientific report on this new test of circulating DNA levels has been published by Goodall et al. in the journal Cancer Discovery.

The utility of this test will clearly be limited to those patients with forms of prostate cancer that are not responding well to standard therapies and in whom either germline or tumor mutations involving the BRCA genes are known or suspected.

A second media release comes from a company called OTraces in Maryland. According to the company, they have been working on — and have now validated — a new type of blood test that might be able to better define men who have aggressive forms of early stage prostate cancer. This research has been carried out in collaboration with a team at Johns Hopkins under the direction of Dr. Ken Pienta.

According to the information in the media release, the new test can identify aggressive forms of prostate cancer with a very high level of sensitivity (95 percent) and specificity (87 percent). However, what the media release does not tell us is how “aggressive” prostate cancer is being defined or how the test works from a scientific perspective. There are already other tests that claim to be able to identify aggressive forms of prostate cancer as compared to “not cancer” (e.g., benign prostatic hyperplasia and chronic prostatitis), so the clinical value of this new test remains to be fully established as compared to the tests that are already available. The media release also does not provide any link to actual, published, peer-reviewed data.

Assuming that published scientific information about this new test supports the claims being made in this media release, we would assume that this test might be used in conjunction with a prostate biopsy to confirm the presence of high-risk prostate cancer in men being diagnosed with signals of potential such high-risk (i.e., a clinical stage of T2b or higher or a PSA level of >10 ng/ml). However, more information about this test will be essential before it is likely to have widespread utility.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.

%d bloggers like this: