Pathwork Diagnostics

Redwood City, CA, August 29, 2011 – Pathwork Diagnostics, Inc., a privately held molecular diagnostics company focused on oncology, announced that results of a study evaluating the use of its Pathwork® Tissue of Origin Test in patients with cancer of unknown primary (CUP) were published in the Journal of Molecular Biomarkers and Diagnosis. The Tissue of Origin Test aids in the diagnosis of challenging cancer cases such as those that are metastatic or that have a complex clinical history.

In the study, the researchers retrospectively performed the Tissue of Origin Test on biopsy specimens from patients with CUP. Assay results were correlated with clinical and pathologic features and treatment results. The Tissue of Origin test provided predictions of the primary site in 96% of patients with CUP. Predictions were generally consistent with clinicopathologic features.

CUP accounts for approximately 2-5% of all cancer diagnoses. Although several clinical subsets with specific treatment implications have been identified, the majority of patients receive “broad- spectrum,” empiric chemotherapy which is only modestly effective, producing median survivals of 9-11 months.1-3
“As treatments improve for specific cancer types, it becomes more important to identify the tissue of origin in patients with CUP so that site-specific therapy can be administered,” explained lead researcher John D. Hainsworth, M.D., Chief Scientific Officer, Sarah Cannon Research Institute, Nashville, TN. “Accurate identification could allow these patients to benefit as treatments targeted for specific malignancies improve in the future.”

The study article, Molecular Tumor Profiling in the Diagnosis of Patients with Carcinoma of Unknown Primary Site: Retrospective Evaluation of Gene Microarray Assay, was authored by Dr. Hainsworth, Raji Pillai, W. David Henner, Meredith Halks-Miller, Cassie M. Lane and F. Anthony Greco.

In the study, the Tissue of Origin test was successfully performed in 45 tumor specimens. In 43 of 45 assays (96%), a specific tissue of origin was predicted. The most commonly identified tissues of origin included: lung (11), pancreas (6), sarcoma (6), ovary (5), and colon (4). Most diagnoses were compatible with the clinical features, IHC staining, and response to treatment.

The Tissue of Origin Test results were also correlated with previous CUP test results using a molecular 10-gene RT-PCR CUP assay designed to detect 6 primary cancer sites. The Tissue of Origin test provided predictions in a higher percentage of patients than did the CUP assay (96% versus 53%). Agreement between the Tissue of Origin test and the CUP assay was relatively low, possibly related to the limited number of genes assessed by the CUP assay.

About Pathwork Diagnostics
Pathwork Diagnostics, Inc. is a privately held company based in Redwood City, CA, that develops and commercializes high-value molecular diagnostics for oncology. For more information call toll-free (877) 808-0006 or visit www.pathworkdx.com.

1. Hainsworth JD, Erland JB, Kulman LA, et al (1997) Carcinoma of unknown primary site: Treatment with 1-hour paclitaxel, carboplatin, and extended schedule etoposide. J Clin Oncol 15: 2385-2393.
2. Greco FA, Burris HA, Litchy S, et al (2002) Gemcitabine, carboplatin, and paclitaxel for patients with carcinoma of unknown primary site: A Minnie Pearl Cancer Research Network study. J Clin Oncol 20: 1651-1656.
3. Culine S, Lortholary A, Voigt JJ, et al (2003) Cisplatin in combination with either gemcitabine or irinotecan in carcinomas of unknown primary site: Results of a randomized phase II study – Trial for the French Study Group in Carcinomas of Unknown Primary (GEFCAPI01). J Clin Oncol 21: 3479-3482.