By Admin at 27 Apr 2017, 11:07 AM

New research is helping to make liquid biopsies a readily available alternative to invasive biopsies for cancer patients. Traditional tissue biopsies have historically been necessary to make definitive cancer diagnoses, but such procedures are invasive, costly and carry risks to the patient.

Liquid biopsies are non-invasive blood tests used to detect cancer cells or pieces of tumor DNA that may be circulating in the bloodstream. A series of studies presented at the 2017 American Association for Cancer Research Annual Meeting in Washington, D.C. highlighted recent advancements in replacing surgical biopsies with liquid biopsies.

Liquid Biopsy for Non-Small Cell Lung Cancer (NSCLC)

Immunotherapy targeting the PD-1/PD-L1 pathway, which suppresses the body’s cancer-fighting abilities, is a promising treatment for NSCLC. A biopsy is required to determine patients’ eligibility for the treatment, but the tumor’s location may make this difficult or impossible.

Many patients with advanced NSCLC suffer from fluid surrounding the lungs, known as malignant pleural effusions. When the lungs are drained, the fluid can be tested for PD-L1, providing a potential alternative to tissue biopsy.

When the fluid from 66 patients was tested, nearly all (63) had circulating tumor cells (CTCs) present. Twenty-three percent had detectable PD-L1 expression, which suggests such a test may be useful on a larger scale.

Liquid Biopsy for Prostate Cancer Patients

A separate study looked into circulating tumor cell clusters, in which CTCs are found in groups in the bloodstream — a finding linked to an increased likelihood of cancer spread.

When researchers tested the blood of prostate cancer patients, nearly 45 percent of them had clusters of CTCs. The researchers plan to look into whether clusters of CTC are correlated with other disease markers measured via blood test, like prostate-specific antigen (PSA) and Chromogranin A (CgA), to determine if they’re linked with more aggressive cancer.

Liquid Biopsy for Pancreatic Cancer

University of Pennsylvania researchers are also hoping to develop a non-invasive method for pancreatic cancer diagnosis and monitoring. Liquid biopsies are ideal for the latter, as blood tests can be administered regularly — something that cannot be done with conventional tissue biopsies.

The study is aimed at finding and isolating CTC clusters in pancreatic cancer in order to analyze them and find out more about the cancer’s molecular makeup.

Liquid Biopsy for Barrett’s Esophagus

Barrett’s esophagus is known to increase the risk for esophageal cancer. Researchers are conducting a comparison of diseased and healthy tissue from such patients on a single cell level, in the hope of understanding why the condition sometimes leads to cancer and developing a non-invasive blood test that could be used to diagnose Barrett’s esophagus.

Ultimately, expanding the use of liquid biopsies in favor of surgical biopsies will minimize risks to patients while allowing doctors to monitor any changes occurring within the tumor in real-time. Liquid biopsies may also allow for cancer detection at earlier stages, which could prove to be life saving for high-risk patients.

Source
EurekAlert March 29, 2017

Post a comment

Make me anonymous

CAPTCHA
Below question is to prevent automated spam submissions.

* Math Question:

2 + 1 =

Solve this math problem and enter the result. E.g. for 1 + 3, enter 4.

You must provide a response to the reCaptcha challenge.