This news release summarizes findings from a pilot study on a device that would screen for prostate cancer in men by “smelling” urine samples. The device employs gas chromotography, which separates and detects the presence of certain compounds in the urine, along with computer algorithms. The pilot study of 155 patients included those already diagnosed with prostate, bladder, haematuria or poor stream but without the presence of cancer. The researchers claim the device, which is still under development, accurately identified urological cancers from the samples. The release would have been improved had it given more attention to the device’s benefits and evidence found in the study and placed less emphasis on the “urgency” of early diagnosis.
Currently, in the United States the standard test for prostate cancer is a biopsy. The prostate-specific antigen (PSA) blood test, once widely used, is no longer recommended by many medical organizations. Universal screening of men using the PSA test does not lead to a decrease in mortality. On the contrary, it produces a high level of false positives leading to unnecessary biopsies and mental anguish. Prostate cancer is a common cancer in men, but accurate diagnosis is important because the symptoms are often confused with benign disorders. Also, some small prostate cancers are so slow growing they are sometimes not treated. Finding an improved method for diagnosing this disease is desirable and important.
There is no mention of the cost of this diagnostic test aside from the implication that it would be inexpensive. A lead researcher of the device states, “With help from industry partners we will be able to further develop the Odoreader, which will enable it to be used where it is needed most; at a patient’s bedside, in a doctor’s surgery, in a clinic or Walk In Centre, providing fast, inexpensive, accurate results.”
The release is clear that this was a pilot study and that the system is not yet available for mass use. That’s good. But the release does speculate that the test might mean that “invasive diagnostic procedures that men currently undergo eventually become a thing of the past.”
We think that if it’s not too soon to speculate about these kinds of benefits, it’s not too soon to provide some idea of what the test might cost.
There is no quantification of the benefits. An allusion is made to the necessity of early diagnosis and the eventual ease of testing, but there is no quantification of how this test compares to other tests. It is unknown how accurate the test might be when used in the general population (no discussion of sensitivity or specificity) or if a biopsy will be needed if the test is positive or if the test will detect cancer at a stage that can be cured nor if it will lead to a decline in mortality. Thus, benefits cannot be quantified and they release should have made that clear.
The release speculates about potential benefits, but never acknowledges that the test might have downsides similar to the PSA test. False-positive results could lead to unnecessary biopsies and take a psychological toll on men who are tested — the release should have mentioned this.
We liked that this release is fairly clear about the fact that this was a preliminary study and the test is not yet ready for general use. However, there is no mention of any of the findings that appear in the published report. The release does not state more than that the screens were successful. In the study, the test distinguished between prostate and bladder cancer without overlap and the results were found to be statistically significant. In addition, the release should have pointed out that the study was not blinded, that the patients were not representative of the general population and that the results, while promising, may not be that good if used in a general population.
The release doesn’t engage in disease mongering, but we were concerned that the release unjustly pushes the “urgency” of the need for testing. More on that under the “Unjustifiable language” section below.
The funding sources are stated and the origins of the equipment being used and tested is also made clear in the release.
The story goes into some detail about how this test might compare with the PSA test and gives a brief mention of biopsies. The lead author states: “There is currently no accurate test for prostate cancer, the vagaries of the PSA test indicators can sometimes result in unnecessary biopsies, resulting in psychological toll, risk of infection from the procedure and even sometimes missing cancer cases.does indicate that the PSA test is problelmatic for false positives.”
It is clear that this screening tool is still in development and that the developers are seeking funders to expand the testing.
The device is similar to many other technologies in development that are said to “sniff” cancer based on specific odor signatures. But the release makes it sound as though this device is unique.
The release contains several instances of unjustifiable language when it calls the test “revolutionary” and says earlier diagnosis is “urgent.” Examples:
In fact, earlier diagnosis often does not yield expected benefits, because it’s difficult to tell which cancers are aggressive and fast-growing and which ones grow so slowly that they would never cause a problem during the patient’s lifetime.
The release also suggests the test could replace biopsy when there’s no evidence for that. “An accurate urine test would mean that many men who currently undergo prostate biopsy may not need to do so,” according to the release.