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New, Improved Blood Test for Prostate Cancer . . .

October 5, 2009. Claims on behalf of the EPCA-2 prostate cancer biomarker blood test study that we reported on in April 2007 (below) in our opinion today cannot be accepted without further evidence, independent of the inventor's team.

According to information laid out by Oconome, Inc. in legal complaints (original and amended) this September in US District Court (Pittsburgh) against Dr. Robert H. Getzenberg and the University of Pittsburgh:

In early 2007, Onconome learned that the respected medical journal Lancet had rejected Dr. Getzenberg's EPCA-2 research paper. Lancet rejected the paper because the Lancet editors were not confident enough in the paper's data and conclusions to publish Dr. Getzenberg's work, even as a proof of principal paper. As the Lancet editor put it in rejecting the paper:

"the editors here are no longer confident enough in the proof for us to publish the concept. There are just too many lingering doubts, too many i-s not dotted and t-s not crossed for us to proceed.. . . [W]e must finally and firmly reject this paper."

Under ordinary circumstances, the fact that one medical journal, like the Lancet, rejects a paper while another, in this case Urology, accepts it would not be cause to question the authenticity of the research. But Onconome's complaint cites information which, althoughnot yet adjudicated nor even fully presented, makes it impossible for us as lay readers to stand behind Urology and against the judgement of the Lancet. This is not the place to lay out all of Onconome's allegations. To mention just one example. Onconome's complaint alleges:

Dr. Getzenberg's own researchers were not able, outside of the Getzenberg lab, to reproduce the results he claimed for his assays. When one of his researchers came to Onconome in late 2006, he ran the assay repeatedly, using the same protocols and procedures used in the Getzenberg lab, and it did not work.

In their legal complaint Onconome Inc. also allege and claim that:

Despite the many historical assertions to the contrary, the Getzenberg laboratory now admits that their immunoassay worked just once in late 2005, for one run, one researcher alone, and never worked before or since for either this researcher or anyone else. The laboratory also confirms that this researcher 'forgot' to keep hard copy records of this one special run, despite federal law requiring such records. In short, the assay was not and is not real.

Dr. Getzenberg, in a phone call September 10, said that the blood test is going ahead and the lawsuit is "about money." J. Strax

For more information see these 2 entries so far in our blog and watch for follow ups:
Company Sues Cancer Scientist for Fraud, Says EPCA-2 Prostate Test Never Worked
September 10, 2009
Prostate Test Going Ahead, Hopkins Scientist Says
 September 10, 2009

New, Improved Blood Test for Prostate Cancer May Be On the Way

April 26, 2007 — New studies of a blood protein recently identified at Johns Hopkins, early prostate cancer antigen-2 (EPCA-2), may change the way men are screened for prostate cancer - a disease that kills tens of thousands of men every year.

Current standards of screening and testing for prostate cancer focus on the blood protein prostate-specific antigen (PSA) along with a digital rectal examination. Men who have more than 2.5 nanograms per milliliter of PSA are considered at risk for prostate cancer.

However, PSA testing often highlights noncancerous conditions (false positives) and can miss some cancers (false negatives).

In a study published in the April issue of the journal Urology, the team of Hopkins researchers introduce evidence in support of EPCA-2 testing as a more accurate way to identify cancer in the prostate.

Robert H. Getzenberg, Ph.D., who identified the EPCA-2 marker and is lead author of the study, says results of this recent study show that the test "has high sensitivity and specificity and accurately differentiates between men with organ-confined and non-organ-confined disease."

Getzenberg says larger clinical trials for EPCA-2 are planned that could make this test available to the public in approximately 18 months.

Currently in the USA about 1.6 million men per year undergo prostate biopsies, and roughly 80 percent of these men have negative results, according to Getzenberg. Of the entire population of men in the United States who have been tested for PSA, Getzenberg says, an estimated 25 million have elevated PSA levels and a biopsy of the prostate that did not reveal any prostate cancer. On the hidden side of the scale, roughly 15 percent of men with prostate cancer go undetected because their PSA levels are below the cutoff level, he says.

Advantages Claimed for the New Test

"A blood test based on EPCA-2 may greatly improve our ability to accurately detect prostate cancer early and minimize the number of false positives, therefore lowering the number of unnecessary biopsies," says Getzenberg. "In addition, this is the first time we have a test that effectively distinguishes between men with cancer confined to the prostate and those whose disease has spread outside of the gland."

Getzenberg and his team measured EPCA-2 levels in the blood of 330 Hopkins patients separated into several groups:

  • men with normal PSA levels and no evidence of disease;
  • men with elevated PSA levels but who had negative biopsies,
  • men with a common noncancerous prostate condition known as benign prostatic hypertrophy (BPH) who did not receive biopsies for prostate cancer,
  • men with prostate cancer but with normal PSA levels,
  • men with prostate cancer confined to the prostate,
  • men with prostate cancer that had invaded outside of the gland at the time of surgery,
  • and a diverse group of patients with benign conditions of other organs as well as individuals with other cancer types.

Patients with an EPCA-2 cutoff level of 30 ng/ml (nanograms per milliliters) or higher were considered to be at risk for prostate cancer. [Note, this was the EPCA-2 level used and must not be confused with PSA levels that are diagnositic of prostate cancer at much lower levels.] This cutoff was based on a pilot study of 30 blood samples, which was then applied throughout the larger study.

Results showed that the EPCA-2 test with that cutoff level was negative in 97 percent of the patients who did not have prostate cancer. Men with no evidence of disease (regardless of their PSA levels), as well as the control group of patients with other cancer types and benign conditions, all had EPCA-2 levels below the cutoff.

In contrast, in a multi-institutional study published in 2003 in the Journal of Urology, PSA levels between 4 and 10 ng/mg were shown to be accurate in identifying patients without prostate cancer only 19 percent of the time.

Most of the 27,000 men per year who are diagnosed with prostate cancer are in the over-50 age group that is commonly prone to benign prostate overgrowth. Getzenberg's study found that 77 percent of the BPH patients had a level of EPCA-2 lower than the cutoff point. Getzenberg says this is well within the likely percentage range of BPH patients who are prostate-cancer free. He says this result was encouraging since BPH is often associated with elevated PSA levels, leading to misdiagnosis and unnecessary biopsies.

When it came to correctly identifying patients with prostate cancer, EPCA-2 levels at or above the cutoff were detected in 90 percent of the men with organ-confined prostate cancer and in 98 percent of the men with disease outside the prostate. Overall, in this study, the EPCA-2 test detected 94 percent of the men with prostate cancer.

Results of the study also revealed that EPCA-2 levels were significantly higher in patients whose cancers had spread outside the prostate compared to those with disease confided to the gland. EPCA-2 was dramatically better at separating these groups than were PSA levels, according to Getzenberg.

"This is important, since cancer that has spread outside the prostate is more deadly, which makes it even more crucial to have a tool that detects it early," says Getzenberg.

Finally, the EPCA-2 test identified 78 percent of the men with prostate cancer in the group with PSA levels below the accepted cutoff level of 2.5 nanograms per milliliter. According to their PSA levels, these were all "healthy men," but EPCA-2 was able to show that they had prostate cancer.

EPCA-2 is the second prostate-cancer marker identified by Getzenberg and his team that has outperformed PSA. Last year, they discovered an unrelated, tissue-based test, EPCA-1, that also proved effective at identifying prostate cancer. The only commonality between these markers is that they were discovered using the same approach. Getzenberg says the efficacy of EPCA-1 as a test of biopsy samples is currently being evaluated.

Abstract of the Urology aricle:

EPCA-2: a highly specific serum marker for prostate cancer. Leman ES, Partin AW, Getzenberg RH et al. Brady Urological Institute, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, USA. Urology, 2007 Apr;69(4):714-20.

Objectives

To describe the initial assessment of early prostate cancer antigen (EPCA)-2 as a serum marker for the detection of prostate cancer and to examine its sensitivity and specificity.

Methods

Serum samples were obtained from 385 men: those with prostate-specific antigen (PSA) levels less than 2.5 ng/mL, PSA levels of 2.5 ng/mL or greater with negative biopsy findings, benign prostatic hyperplasia, organ-confined prostate cancer, non-organ-confined disease, and prostate cancer with PSA levels less than 2.5 ng/mL. In addition, a diverse group of controls was assessed with an enzyme-linked immunosorbent assay to detect an epitope of the EPCA-2 protein, EPCA-2.22.

Results

Using a cutoff of 30 ng/mL, the EPCA-2.22 assay had a 92% specificity (95% confidence interval 85% to 96%) for healthy men and men with benign prostatic hyperplasia and 94% sensitivity (95% confidence interval [CI] 93% to 99%) for overall prostate cancer. The specificity for PSA in these selected groups of patients was 65% (95% CI 55% to 75%). Additionally, EPCA-2.22 was highly accurate in differentiating between localized and extracapsular disease (area under the curve 0.89, 95% CI 0.82 to 0.97, P <0.0001) in contrast to PSA (area under the curve 0.62, 95% CI 0.50 to 0.75, P = 0.05).

Conclusions

The results of our study have shown that EPCA-2 is a novel biomarker associated with prostate cancer that has high sensitivity and specificity and accurately differentiates between men with organ-confined and non-organ-confined disease.

Funding for the study was provided by the National Cancer Institute of the National Institutes of Health, and Onconome Inc. Under a licensing agreement between Onconome Inc. and the University of Pittsburgh, Getzenberg is entitled to a share of royalty received by the University on sales of products described in this manuscript. Getzenberg also is a paid consultant to Onconome Inc., which has a licensing agreement with The Johns Hopkins University covering EPCA-2 and related technologies. The terms of this arrangement are being managed by The Johns Hopkins University in accordance with its conflict of interest policies.

Other researchers from the Brady Urology Institute at Johns Hopkins who contributed to this study are Eddy S. Leman, Ph.D.; Department of Urology Chairman Alan W. Partin, M.D., Ph.D.; Daniel W. Chan, Ph.D.; Bruce J. Trock, Ph.D.; Lori J. Sokoll, Ph.D.; Leslie Mangold, and Grant W. Cannon.

This page made by J. Strax, April 26, 2007. Last modified, October 5, 2009.

Recent news (2009)

Information on this website is not intended as medical advice nor to be taken as such. Consult qualified physicians specializing in the treatment of prostate cancer. Neither the editors nor the publisher accepts any responsibility for the accuracy of the information or consequences from the use or misuse of the information contained on this website.

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