New research from the University of East Anglia (UEA) and Norwich University Hospital has yielded promising new developments in a simpler and more efficient test for prostate cancer detection. This at-home test only requires small samples of urine, and may even replace the current prostate exam in the future. The current prostate exam is considered uncomfortable and invasive by most men, meaning this new, easier test holds a lot of medical promise. Prostate exams are constantly being used to help doctors diagnose enlarged or inflamed prostates, both of which may indicate prostate cancer, the second most common form of cancer among American men. Currently, an estimated 4 million American men are living with undetected prostate cancer due to unchecked prostates, causing the deaths of around 30,000 men per year. The at-home urine test may prevent such deaths by providing a non-invasive test that makes enforcing routine prostate exams much easier than it currently is.
This new and improved prostate exam also presents a scientific explanation that patients are capable of following along with, due to elimination of any inaccuracies that come with current prostate exams. Researchers focused their experiment on the zones of the prostate where tumors are found to constantly produce secretions that naturally flow into the urethra, or where urine is excreted from [6]. These secretions carry cancer cells and cell-free RNA (cfRNA) contained within extracellular vesicles, or cellular sacs, that are flushed out of the body upon urination. cfRNA is a promising analyte that is recurrently detected as a biomarker in individuals with cancer. RNA can be harvested from urine and examined for the presence of prostate cancer (PCa) transcripts and prognostic markers (biomarkers used to measure the progress of a disease in the patient sample) [3,4]. These PCa transcripts and prognostic markers are what essentially “set off” prostate cancer detection, as higher levels of these products, in addition to higher amounts of cell-free RNA and cell-tumor DNA serve as promising diagnostic tools to indicate cancer onset. The contents of the urine test would then be analyzed by laboratory professionals who identify the amounts of PCa and cfRNA present in the patient’s urine. Certain levels of each biomarker would then indicate the likeliness and/or presence of prostate cancer in the patient.
Feedback from the research study’s participants showed that the at home test was preferable. The results of volunteer home urine samples, taken first thing in the morning, were compared with samples collected after a digital rectal examination [5]. The researchers found that the urine samples taken at home showed the biomarkers for prostate cancer much more clearly than after a rectal examination [2]. Using the At-Home test could, in the future, revolutionize how those on 'active surveillance' are monitored for disease progression, with men only having to visit the clinic for a positive urine result. In the case that prostate cancer is diagnosed, patients go on to an active surveillance program following the diagnosis which may involve repeat biopsies and MRI scans which are quite intrusive. This is in stark contrast to current situations, where men are recalled to the clinic every six to 12 months for painful and expensive biopsies. Dr. Jeremy Clark, one of the lead scientists behind this new research at UEA, stated: “A negative test could enable men to only be retested every two to three years, relieving stress to the patient and reducing hospital workload” [7]. The research team even thinks that their findings could also help pioneer the development of home-collection tests for bladder or kidney cancer.
While some may believe that this new test is not as reliable as doctors physically checking for prostate abnormalities, it has been proven by the researchers that this urine test provides all the information given by a normal prostate exam and more, even predicting the severity of prostate cancer detected up to five years earlier than standard clinical methods. This in turn allows doctors to better determine a patient’s possible treatment plan. This is an important step forward, because the first urination of the day provides biomarker levels from the prostate that are much higher and more consistent, making it easier for doctors to predict which tumors will become aggressive and how best to remove the tumor [1]. It is with this new advancement in medicine that many hope prostate cancer diagnosis and treatment can become a much more accessible and feasible option for men across the world.
References:
1. Gillespie, T. (2019, November 29). Home urine test could revolutionise prostate cancer diagnosis. Sky News. https://news.sky.com/story/new-prostate-cancer-test-could-involve-collecting-urine-sample-at-home-11873122.
2. Knowridge. (2020, May 30). This new test may revolutionize diagnosis of prostate cancer. Knowridge Science Report. https://knowridge.com/2020/05/this-new-test-may-revolutionize-diagnosis-of-prostate-cancer/.
3. Larson, M.H., Pan, W., Kim, H.J. et al. A comprehensive characterization of the cell-free transcriptome reveals tissue- and subtype-specific biomarkers for cancer detection. Nat Commun 12, 2357 (2021). https://doi.org/10.1038/s41467-021-22444-1
4. Nature Publishing Group. (n.d.). Prognostic markers. Nature news. https://www.nature.com/subjects/prognostic-markers
5. ScienceDaily. (2019, November 30). Home urine test for prostate cancer could revolutionize diagnosis. ScienceDaily. https://www.sciencedaily.com/releases/2019/11/191130092056.htm.
6. Webb, M., Manley, K., Olivan, M., Guldvik, I., Palczynska, M., Hurst, R., Connell, S. P., Mills, I. G., Brewer, D. S., Mills, R., Cooper, C. S., & Clark, J. (2020). Methodology for the at-home collection of urine samples for prostate cancer detection. BioTechniques, 68(2), 65–71. https://doi.org/10.2144/btn-2019-0092
7. Wooller, S. (2019, November 29). Home pee test for prostate cancer 'detects it 5 years earlier & could save thousands of lives'. The Irish Sun. https://www.thesun.ie/news/4829267/home-pee-test-for-prostate-cancer-detects-it-5-years-earlier-could-save-thousands-of-lives/.