No blood test Cancer diagnosis based on urine?

Cancer diagnosis: Peeing instead of pissing?

Urinalysis is one of the oldest methods of studying certain diseases such as kidney or urinary tract. The excretion can generally say a lot about our state of health. Urine could also be used for cancer diagnosis, as researchers now report.

Number of cancers is increasing

Health experts say more and more people are getting cancer. In Germany alone, around half a million new cases are registered each year. The number of diagnoses has almost doubled in this country since 1970. However, patients today can hope for recovery more than before. Important for this, however, is the earliest possible diagnosis. According to researchers, urine could also be used for cancer diagnostics.

So far, tests for cancer diagnosis usually work with blood samples. Researchers now report that urine is also available for cancer diagnostics. (Image: Gerhard Seybert / fotolia.com)

Genetic material from urine

Researchers from the Christian-Albrechts-Universität Kiel (CAU), the University Medical Center Schleswig-Holstein (UKSH) and the Lithuanian University of Health Sciences in Kaunas are convinced of the diagnostic potential of urine.

The reason for this is the genetic material contained therein, which offers new possibilities for cancer diagnostics as so-called cell-free DNA, according to a statement from Kiel University.

According to the researchers, out of a quantity of 60 milliliters of urine - about half a urine cup - researchers were able to obtain as much genetic material in the laboratory as they would from a blood sample of ten milliliters.

For this, the team of scientists worked on new methods to extract the cell-free DNA from the urine.

The researchers of the Institute for Clinical Molecular Biology (IKMB) at the CAU published their results in cooperation with their international colleagues in the journal "BioTechniques"..

Amount of DNA in the urine varies greatly from person to person

As explained in the communication, the term cell-free DNA refers to fragments of genetic information that are outside of cells in different body fluids.

These DNA components are formed when body cells but also tumor cells die off. They are first released into the bloodstream and from there, among other things, continue to enter the urine.

The scientists first came across a number of problems: The amount of DNA in the urine varies greatly from person to person, and varies greatly from day to day, even in the same person.

For this reason, the DNA concentrations initially contained in the samples were sometimes too small, so that the researchers had to increase the amount of urine collected.

They also regularly observed that the urine of healthy women contains more than twice as much of the diagnosis-promising cell-free DNA as an identical amount in healthy men.

This fact must be taken into account in future cancer diagnostics, so that these gender differences do not distort the results.

Tests for cancer diagnosis usually work with blood samples

So far, tests for cancer diagnosis usually work with blood samples. Some of these blood tests use cell-free DNA from a possible tumor to detect certain types of lung or colon cancer.

Whether the genetic material from the urine is just as well suited for clinical research and diagnostics as blood, the experts would like to clarify in the next twelve months in the laboratory of the IKMB at Kiel University in further research.

"For this purpose, we will compare the genetic traces of a tumor in the blood plasma and urine on the basis of the available samples from the study participants at the UKSH and see if the disease can be detected in both ways", says Michael Forster, scientist at the Institute for Clinical Molecular Biology of the CAU.

Benefits for patients

The researchers in Kiel hope to develop a urine-based procedure in the future, which allows just as reliable diagnoses as conventional blood tests. This would initially offer advantages for patients who would be spared the unpleasant blood collection.

In addition, such a test procedure would be faster and less expensive than the previous methods, since, for example, unlike blood tests, no medical personnel are required for the sampling.

"In the US, similar test methods for cancer diagnosis are already commercially available. Recently, an international research team also presented a newly developed, not yet clinically approved urine test for certain urinary tract tumors, "Forster describes the current state of development.

And British researchers reported years ago on a urine test that can diagnose pancreatic cancer.

"Until the introduction of new urine-based clinical tests in Germany, several years will pass for clinical research and cost and benefit considerations," said Forster. (Ad)