Dr. Glen Weiss

New imaging method may be better than biopsies

July 08, 2014
by Lauren Dubinsky, Senior Reporter
In order to determine if a patient’s tumor has the cancer-causing KRAS mutation, a biopsy would usually be done but that could lead to problems for sensitive areas of the body including the lungs. However, a new medical imaging technique may help clinicians determine a more accurate treatment and enhance treatment management for lung cancer patients, according to a recent study published in the journal PLOS ONE.

Quantitative computed tomography-based texture analysis (QTA) is a non-invasive alternative to biopsies and other invasive procedures to collect and analyze biological samples.

Researchers at the Translational Genomics Research Institute scanned 48 patients with non-small cell lung cancer (NSCLC) with QTA and found that it can determine if the patients’ tumors had the KRAS gene mutation with 90 percent accuracy.

“If validated in other independent sample sets, this could be a useful clinical tool for non-invasive tumor characterization of KRAS in NSCLC,” Dr. Glen Weiss, the study’s lead author and director of clinical research and medical oncologist at Cancer Treatment Centers of America’s western regional medical center, wrote in an email to DOTmed News. “Ideally, that could be evaluated shortly after a patient's CT scan, and have a faster turnaround time than laboratory molecular testing.”

QTA will help clinicians determine the best treatment for NSCLC because if a patient has a tumor with a KRAS mutation then they will know to avoid epidermal growth factor receptor inhibitor therapy, because it is unlikely to work, wrote Weiss.

QTA determines if a tumor has the KRAS mutation by quantifying lesion heterogeneity based on the distribution of pixel intensities within a region. When the tumor is being visualized on the CT scan, the differences in the pixel intensity areas are analyzed for tumors known to have mutated KRAS and those that have wild-type or non-mutated KRAS.

In the future, QTA may be used as an adjunct that can assist with the major mutations or genomic abnormalities, wrote Weiss. However, since there are so many different types of mutations, to get enough sample sets to validate them all may be a “monumental amount of work.”

Going forward, the researchers plan to evaluate other major mutations and genomic abnormalities pertaining to NSCLC and they plan to validate QTA for KRAS from other independent sample sets.