Routine biopsies are crucial to fighting cancer because they help track down how the disease is progressing.

Unfortunately, the procedure is never pleasant. Fortunately, a new method has been developed, easing the process for cancer patients.

Instead of taking a sample from tumor tissue, liquid biopsies capture DNA shed by tumors or cancer cells in the blood. Due to the repeated nature of sampling for cancer treatment, this noninvasive procedure simplifies taking samples, making it easier to make adjustments toward a treatment plan.

Liquid biopsies were rarely used before except in research, but now, more and more doctors are including them in routine care. At the University of Texas MD Anderson Cancer Center, for instance, around 10 percent of patients diagnosed with metastatic colon cancer are getting the procedure instead of the usual biopsy methods.

It is clear that liquid biopsies have a lot of potential, the only problem is that there aren't any definitive studies available proving that they do present a benefit to patients as well as which kind are best for which conditions and who should get them and when.

At the moment, liquid biopsies are recommended when a tissue biopsy is difficult, such as in the case of lung cancer, or when the original site of the disease is unknown. As a test, a liquid biopsy is a simpler way of letting doctors explore another avenue of treatment when current therapies are no longer working for a patient.

Early liquid biopsies focused on searching for whole tumor cells in the bloodstream. Newer ones check for free-floating cancer DNA instead, making gene profiling possible to assess which mutations are driving cancer growth.

However, whether or not the procedure is cost-effective is yet to be seen. One test, for example, costs $5,400. Liquid biopsies are not covered by all insurance plans. Typically, providers cover them for specific kinds of patients. However, compared with gene profiling, costs are similar. On the other hand, liquid biopsies can help save on other costs, like doing away with drugs that don't work, many of which possibly costing up to $15,000 per month.

Essentially, liquid biopsies offer another way to check for cancer aside from the usual colonoscopies, mammograms and other methods. Besides providing a means to screen for disease more easily, test results can also come out faster, allowing for a more prompt response to cancer treatment.

Several companies are currently in the process of developing liquid biopsy tests, including Guardant Health Inc. and Trovagene.

Photo: National Eye Institute | Flickr

ⓒ 2021 All rights reserved. Do not reproduce without permission.