When many diagnoses of cancer require a biopsy and at least a blood test involving needles and injections, many people are dreaming about a noninvasive diagnosis. Well, this dream seems to come true. Scientists have found that urine can help detect cancer.
How can urine detect cancer?
First, evidence of cancer may come from kidneys. Cancer cells will release some molecules like proteins, which are so small that they can reach the kidneys through the blood. These molecules will then travel to urine.
Second, evidence of cancer may come from bladder and ureters, tubes connecting the kidneys to the bladder. Entire cancer cells or their DNA are so big that they cannot reach the kidneys. Instead, they may be in ureters and bladder.
In these two cases, evidence of cancer may eventually be found in urine. In addition, the virus leading to cancer may also be found there. For example, scientists can detect the HPV causing cervical cancer easily in the urine.
Testing urine for bladder cancer
For now, the blood in the urine is the first alert for bladder cancer. But only one fifth of people with urine in the blood have bladder cancer.
In order to find a more accurate way to detect bladder cancer, the researchers are trying to observe the DNA fragments of the cancer cells in the urine. And they have already tested 800 urine samples.
"We have a very promising experimental test that identifies the most common genetic changes seen in bladder cancer," said Richard Bryan.
Testing urine for pancreatic cancer
For now, it is very difficult to diagnose pancreatic cancer at early stage because many patients have no symptoms at that time. When symptoms do occur, the cancer often becomes advanced and is hard to treat.
But the researchers have just found three key proteins in the urine which are related to pancreatic cancer.
Diagnosing cancer at early stage is like “looking for a needle in a haystack,” said Professor Tatjana Crnogorac-Jurcevic. "We've already gone through the haystack and found our needles, so now it's really a matter of evaluating our test on large samples of patients."
To conclude, scientists are now planning to recruit patients for clinical trials. Maybe in a foreseeable future, urine test can be put into practice to diagnose cancer.