When treating cancer patients, doctors usually find it helpful to know where the cancer began. That's one reason Rosetta Genomics (Rehovot, Israel) wants to validate its microRNA-based test designed to identify the primary site of cancer of unknown primary (CUP). The company has initiated a clinical validation study of its CUP assay with the University of Texas M. D. Anderson Cancer Center (Houston).
The validation study will include 100 patients who are diagnosed with CUP at M. D. Anderson. Rosetta expects to submit this test for regulatory approval later this year.
"The initiation of this validation study is an integral part of the commercialization roadmap for our diagnostic tests, as we advance them toward use in a clinical setting," said Amir Avniel, president/CEO of Rosetta Genomics. "We believe the initiation of this study for our CUP assay with a leading cancer research center such as M. D. Anderson attests to the critical unmet need this test addresses."
Rosetta said data on its CUP assay and its high sensitivity and accuracy was published in the April issue of Nature Biotechnology.
According to Rosetta, CUP is a heterogeneous group of cancers that constitutes 3% to 5% of all cancers with a poor median survival of six to 10 months. Each year, roughly 70,000 patients in the U.S. are diagnosed with CUP. A patient is typically diagnosed with CUP only after undergoing a wide range of tests, including various imaging tests such as X-ray, CT, MRI, and PET, which often fail to identify the origin of the cancer, the company noted.
Treatment that is specific to the type and location of the primary tumor is more likely to be effective, according to the National Cancer Institute (NCI; Bethesda, Maryland). Rosetta says patients with CUP pose a therapeutic dilemma and treatment is often empiric with a "trial and error" approach. In the era of rapidly growing effective cytotoxic and targeted therapies for known cancers, quicker and more accurate methods of identifying the tissue of origin of CUP cases would permit the use of these therapies, thereby improving the chances of achieving a response and possibly extending the patient's survival, the company said.
"The current gold standard diagnostic evaluation for CUP consists of a careful history and physical examination, laboratory tests, imaging studies, invasive studies when necessary, and thorough pathologic evaluation. This process is lengthy and exposes the patient to unnecessary toxicities," said Gauri Varadhachary, MD, of M. D. Anderson. "Rosetta Genomics' microRNA-based CUP assay may present an alternative test to current diagnostic practices. This study aims to validate their assay as well as compare its performance with current tests for CUP."
According to the NCI, in patients in whom the primary cancer is eventually found, it's usually found in the lung and pancreas. CUP also may be traced to the breast, prostate, colon, or rectum, the organization said.
When diagnostic tests have not identified the cancer's origin, NCI said, doctors must decided whether the potential benefits of extensive testing outweigh the patient's discomfort and the financial costs.
MicroRNAs (miRNAs) are recently discovered, naturally occurring, small RNAs that act as master regulators and have the potential to form the basis for a new class of diagnostics and therapeutics, according to Rosetta. The company develops MicroRNA-based diagnostics and therapeutics.
Rosetta recently acquired Parkway Clinical Laboratories (Bensalem, Pennsylvania) for $2.9 million. The acquisition is expected to allow Rosetta to expedite development and validation of its diagnostic tests worldwide. The company also said that ownership of the CLIA-certified lab would allow it to control the commercialization of its diagnostics, including marketing, sales, and reimbursement strategy (Medical Device Daily, July 25, 2008).