Results from a study involving Pathwork Diagnostics Inc‘s Pathwork® Tissue of Origin Test will be presented this week at the Annual Meeting of the Association for Molecular Pathology (AMP), held November 17 to November 19 in Grapevine, Tex. The Tissue of Origin Test aids pathologists and oncologists in the diagnosis of cancer cases.

Cancers are treated differently based on what type of cancer they are. When the disease is metastatic at the time of diagnosis, determining the type of cancer can be especially difficult. This study evaluated whether pathologists changed their initial or unresolved differential diagnosis when gene expression profiling results from the Tissue of Origin Test were made available to them. The study indicated that more than half of the time the pathologists changed their diagnosis.

“The Pathwork Tissue of Origin test is a valuable adjunct to immunohistochemistry in determining site of origin for lesions that are poorly differentiated or show staining and morphology patterns that are inconsistent with the clinical expectation,” concluded pathologist Maressa Pollen, MD, at Vanderbilt University, Nashville, Tenn.

The retrospective study involved 23 difficult-to-diagnose carcinomas with histopathology reports listing three or more possible sites of origin. In 15 of the 23 cases (65%) the Tissue of Origin test indicated a site of origin different from the initial pathologist-favored site. In all but 2 (13/15) of these cases the pathologist favored the Tissue of Origin test result over their initial diagnosis.

Source: Pathwork Diagnostics