New Blood Test for ROS1 Could Help People with Non-Small Cell Lung Cancer Make Personalized Treatment Decisions

The gist: A new blood test might help people with non-small cell lung cancer (NSCLC) make decisions about their treatment. Doctors often use molecular testing to look for tumor mutations that might affect which treatments they suggest to a patient. Molecular testing requires tumor cells, which are usually taken directly from the tumor in a biopsy. A new, less invasive molecular test for NSCLC just requires a blood sample. The test uses circulating tumor DNA, pieces of DNA released by tumor cells into the bloodstream. It looks for a mutation known as ROS1 gene rearrangement. Patients with this mutation might be able to take specific drugs that target the mutation to treat cancer.

“Biocept, Inc. (Nasdaq:BIOC), a molecular oncology diagnostics company specializing in biomarker analysis of circulating tumor DNA (ctDNA) and Circulating Tumor Cells (CTCs), today announced the launch of ROS1 testing on CTCs, which will help physicians identify which of their patients may be receptive to certain drugs for the treatment of non-small cell lung cancer.

“Biocept’s new blood test identifies chromosomal rearrangements of the gene encoding ROS1 proto-oncogene receptor tyrosine kinase (ROS1), thereby defining a distinct molecular subgroup of NSCLCs. Patients with ROS1-positive tumors may be receptive to a number of therapeutic options that inhibit this target.

“It can be difficult to obtain enough tissue material for molecular testing of biomarkers like ROS1 from lung cancer patients due to the small size of tissue biopsies. Occasionally, tissue biopsies are altogether impossible because of risks associated with a surgical procedure for these patients. Biocept’s ‘liquid biopsy’ offers a method of determining the crucial genomic status of a tumor using a simple blood test.”


ctDNA 'Liquid Biopsy' Could Revolutionize Cancer Care

“Bits of tumor cell somatic DNA shed into the circulation or released when cells die can now be detected and counted, thanks to advances in gene sequencing. This circulating tumor DNA (ctDNA) is derived from somatic mutations that occur in the tumor during an individual’s life, unlike hereditary mutations that are present in every cell in the body, so ctDNA is a specific cancer biomarker that can be detected, measured, and tracked.

“Monitoring ctDNA is expected to provide clinicians with faster, cheaper, less invasive ways to assess cancer patients’ clinical status and response to therapy. ctDNA assay for multiple genes via next-generation sequencing (NGS) might become a ‘liquid biopsy’ alternative to invasive tissue biopsy, experts told Medscape Medical News.

“However, they also cautioned that rigorous testing of this concept is needed before the test can be used in practice, saying: ‘for now, we would counsel clinicians not to jump the gun on this.’ “


Blood Test Accurate in Later Stage Lung Cancer Diagnosis

“Simple blood tests for cancer diagnosis and post-treatment assessment are getting closer all the time. New research has shown that a new assay for measuring circulating tumor DNA (ctDNA) could detect essentially all stage II-IV non-small-cell lung cancers (NSCLC), and is even about 50% sensitive in finding stage I NSCLC as well.”

” ‘Analysis of ctDNA has the potential to revolutionize detection and monitoring of tumors,’ wrote investigators led by senior study author Maximilian Diehn, MD, PhD, of Stanford University School of Medicine, in Nature Medicine. ‘Noninvasive access to cancer-derived DNA is particularly attractive for solid tumors, which cannot be repeatedly sampled without invasive procedures.’ “


Drug Combo May Knock Down Lung Cancer

“Some drug-resistant cancers of the lung, pancreas and breast might be made vulnerable again by treating them with a medication already approved for another type of cancer, according to a new study led by scientists at UC San Diego.

“Researchers at UCSD Moores Cancer Center said they plan to start a clinical trial to test the use of Velcade for lung cancer in about six months. This quick start is possible because the drug is currently on the market, said Dr. Hatim Husain, an author of the study who is designing the clinical trial. For more information about the trial, call (858) 822-5182.”

Editor’s note: Clinical trials can be important treatment options for some patients. This one might be particularly appropriate for people who have taken the drug Tarceva (erlotinib) but became resistant to it. The drug combination being tested in this clinical trial has previously shown disappointing results, but the researchers are hopeful that by using molecular testing to identify patients who are more likely to benefit, they may be able to successfully use the treatment. Learn more about clinical trials here.


Sidestepping the Biopsy With New Tools to Spot Cancer

“For people with cancer or suspected cancer, the biopsy is a necessary evil — an uncomfortable and somewhat risky procedure to extract tissue for diagnosis or analysis.

“Lynn Lewis, a breast cancer patient in Brooklyn, has had her cancer analyzed an easier way: simple blood tests that are being called ‘liquid biopsies.’

“Telltale traces of a tumor are often present in the blood. These traces — either intact cancer cells or fragments of tumor DNA — are present in minuscule amounts, but numerous companies are now coming to market with sophisticated tests that can detect and analyze them.”


Sidestepping the Biopsy With New Tools to Spot Cancer

“For people with cancer or suspected cancer, the biopsy is a necessary evil — an uncomfortable and somewhat risky procedure to extract tissue for diagnosis or analysis.

“Lynn Lewis, a breast cancer patient in Brooklyn, has had her cancer analyzed an easier way: simple blood tests that are being called ‘liquid biopsies.’

“Telltale traces of a tumor are often present in the blood. These traces — either intact cancer cells or fragments of tumor DNA — are present in minuscule amounts, but numerous companies are now coming to market with sophisticated tests that can detect and analyze them.”


Sidestepping the Biopsy With New Tools to Spot Cancer

“For people with cancer or suspected cancer, the biopsy is a necessary evil — an uncomfortable and somewhat risky procedure to extract tissue for diagnosis or analysis.

“Lynn Lewis, a breast cancer patient in Brooklyn, has had her cancer analyzed an easier way: simple blood tests that are being called ‘liquid biopsies.’

“Telltale traces of a tumor are often present in the blood. These traces — either intact cancer cells or fragments of tumor DNA — are present in minuscule amounts, but numerous companies are now coming to market with sophisticated tests that can detect and analyze them.”


Quick, Simple Blood Test for Solid Cancers Looks Feasible

“The idea of a general, quick and simple blood test for a diverse range of cancers just came closer to reality with news of a new study published in Nature Medicine.

“Researchers from Stanford University School of Medicine have devised an ultra-sensitive method for finding DNA from cancertumors in the bloodstream.

“Previous research has already shown circulating tumor DNA holds promise as a biomarker for cancer, but existing methods for detecting it are not sufficiently sensitive and do not cover a diverse range of cancers.

“Ways to increase the sensitivity and coverage of such tests exist, but these are cumbersome and time-consuming, and need lots of steps to customize for individual patients, so they are not feasible for use in clinics.

“The new approach promises to change that. It is highly sensitive and specific and should be broadly applicable to a range of cancers, say the researchers.”


Quick, Simple Blood Test for Solid Cancers Looks Feasible

“The idea of a general, quick and simple blood test for a diverse range of cancers just came closer to reality with news of a new study published in Nature Medicine.

“Researchers from Stanford University School of Medicine have devised an ultra-sensitive method for finding DNA from cancer tumors in the bloodstream.

“Previous research has already shown circulating tumor DNA holds promise as a biomarker for cancer, but existing methods for detecting it are not sufficiently sensitive and do not cover a diverse range of cancers.

“Ways to increase the sensitivity and coverage of such tests exist, but these are cumbersome and time-consuming, and need lots of steps to customize for individual patients, so they are not feasible for use in clinics.

“The new approach promises to change that. It is highly sensitive and specific and should be broadly applicable to a range of cancers, say the researchers.”