Pathwork Diagnostics Inc, launched today an additional version of the Pathwork® Tissue of Origin Test that has the capability of analyzing formalin-fixed, paraffin-embedded (FFPE) tissue specimens. This molecular diagnostic test, which aids in the diagnosis of tumors with uncertain origins, is now available as a service through the CLIA-certified Pathwork Diagnostics Laboratory.
“The capability to work with FFPE specimens will enable our test to be more broadly utilized by oncologists and pathologists,” said Deborah J. Neff, President and Chief Executive Officer of Pathwork. “Due to the RNA degradation that occurs in FFPE specimens, generating robust and reproducible data for many genes simultaneously was a significant challenge. Maintaining the high level of robust and reliable performance for the FFPE version of the test was an outstanding technical accomplishment by the company.”
To determine the tumor’s origin, the Pathwork Tissue of Origin Test uses microarray technology to measure the expression pattern, comprising more than 1,500 genes, in a tumor with an uncertain origin and compares it to expression patterns of a panel of 15 known tumor types, representing 90% of all solid tumors and 58 morphologies overall.
In the clinical validation study utilizing FFPE tumor specimens, the test demonstrated 89% positive percent agreement (akin to sensitivity) with available diagnoses and greater than 99% negative percent agreement (akin to specificity). This statistically significant study consisted of 352 metastatic, poorly differentiated and undifferentiated tumors that had been identified as one of the 15 tumor types on the panel using existing methods.
The American Cancer Society estimates that there are 1.4 million new cancer diagnoses annually in the United States. Of these new cases, up to 10% are of tumor types not readily classifiable in the course of the initial diagnostic workup. Tumors with uncertain origins are among the most frustrating for physicians and place a disproportionate burden on patients, health care professionals, and the health care system.
“Now that the Pathwork Tissue of Origin Test works with FFPE specimens, it will be more easily available for pathologists to utilize,” said Dr. Larry Weiss, chair, division of pathology, City of Hope. “When there is uncertainty about a tumor’s origin, the Tissue of Origin Test holds the promise of delivering unique data not available through other methods, filling the information gap with accurate, objective, actionable information that may allow a patient’s physician to make treatment decisions with greater confidence.”
By utilizing the Tissue of Origin Test, physicians will be able to use objective criteria to identify the primary site of a tumor’s origin, the first step in beginning standard-of-care, tumor-specific therapy per National Comprehensive Cancer Network (NCCN) Clinical Practice Guidelines. Targeting therapy to specific tumor types can also allow patients to avoid the toxicity of broader, and in some cases, ineffective chemotherapy.
The test may also allow physicians to arrive at a diagnosis sooner, which can benefit cancer patients by enabling treatment to begin more quickly and allowing patients to enroll in and benefit from appropriate clinical trials.
With today’s announcement, the Pathwork Diagnostics Laboratory is now able to process and analyze both FFPE and frozen tissue specimens. Upon specimen receipt, Pathwork runs the microarray test on the specimens, and a staff pathologist interprets the test results and provides a comprehensive clinical report to the physician.
Pathwork will seek FDA clearance for the FFPE version of the Tissue of Origin Test in an in vitro diagnostic (IVD) kit format so that pathologists can run the test in their own clinical laboratories.
“The FFPE version of the test will utilize the Pathchip® microarray, which runs on the proven Affymetrix GeneChip® System 3000Dx,” said Kevin King, Affymetrix President and Chief Executive Officer. “We’re proud to partner with Pathwork and congratulate them on being our first partner to validate the Affymetrix platform for FFPE diagnostic tissue specimens. We are excited about the potential for this product and look forward to working collaboratively with Pathwork as they build their diagnostic product line based on the Affymetrix platform.”