Benzinga | Oct 5, 2020 08:03AM EDT

Study Shows Biocept's Target Selector May Provide a More Robust Method for Detecting Lung Cancer Metastasis in Cerebrospinal Fluid than Cytology

SAN DIEGO , Oct. 5, 2020 /PRNewswire/ -- Biocept, Inc. (NASDAQ:BIOC), a leading commercial provider of molecular diagnostic tests and services for physicians treating cancer patients, announces results from a prospective study comparing its Target Selector(tm) cerebrospinal fluid testing to conventional cytology in patients with non-small cell lung cancer (NSCLC) and leptomeningeal metastasis. The results were presented on Friday, October 2, in a virtual poster "Hot Topic: Liquid Biopsy" presentation at the International Association for the Study of Lung Cancer (IASLC) by David Berz, MD, PhD, MPH of the Beverly Hills Cancer Center. The presentation can be found here.

Leptomeningeal metastasis is difficult to diagnose and assess for treatment response using conventional methods such as cytology. In this study, 28 cerebrospinal fluid samples from 15 patients obtained sequentially before and during treatment were compared. Target Selector(tm) improved detection of circulating tumor cells (CTC), finding CTCs in 78% of the samples, whereas cytology detected tumor cells in 55% of samples. Target Selector(tm) also provided sensitive quantitative identification of actionable EGFR mutations in cerebrospinal fluid. In patients with stable disease and partial response, Exon 19 deletion mutant copy numbers decreased, whereas they increased in a patient with progressive disease. Strikingly, alterations in CTC density (CTCs/mL) as well as in EGFR mutant copy numbers were observed weeks before a treatment response was measured via traditional clinical evaluations, such as the RECIST criteria.

"Even in this small study the ability to detect response to this experimental treatment in cerebrospinal fluid using Target Selector(tm) is promising, particularly as the diagnosis of leptomeningeal disease remains challenging using current methods," said Dr. Berz. "Cytological assessment has limited sensitivity and often requires multiple sample collection attempts. In addition, cytology is a qualitative measurement, whereas Target Selector(tm) allows for quantitative assessment of treatment response. Given these encouraging results, additional studies of the use of Target Selector(tm) testing in patients with leptomeningeal disease is highly warranted."

"These results indicate Target Selector(tm) may play an important role in providing valuable information to neuro-oncologists in making treatment decisions for patient with lung cancer metastases to the brain," said Biocept President and CEO Michael Nall. "As more therapies are developed with the ability to cross the blood brain barrier that target specific cancer related gene and protein alterations, analysis of cerebrospinal fluid to inform early detection and subsequent monitoring for treatment response and disease progression will likely become increasingly important."