Pathwork Launches New Version of Tissue of Origin Test

Filed in archive Cancer , Diagnostics on January 13, 2009

Photo courtesy of iStockphoto, Image# 1240328

Pathwork Diagnostics announced today the availability of a new version of the Pathwork Tissue of Origin Test, which aids in the diagnosis of tumors with uncertain origins. The new version uses formalin-fixed, paraffin-embedded (FFPE) tissue specimens, making it much more easily accessible to pathologists and oncologists as FFPE is the most common and preferred method of tissue preservation for labs across the country.

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 percent 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.

When using FFPE specimens, it is sometimes a significant challenge to generate robust and reproducible data for many genes simultaneously due to the RNA degradation that occurs in FFPE specimens, however Pathwork was able to overcome this difficulty and maintain a high level of performance in the FFPE version of the test - 89% positive percent agreement (akin to sensitivity) and greater than 99% negative percent agreement (akin to specificity).

Find more details about this test from Pathwork Diagnostics.