The current diagnostic tools in a pathologist’s arsenal sometimes cannot provide a clear distinction between primary mediastinal large B-cell lymphoma (one of the few lymphomas more common in younger women) and diffuse large B-cell lymphoma, the most common type of non-Hodgkin’s lymphoma overall. This may occasionally give rise to diagnostic inaccuracy in routine practice and could leave physicians guessing as to the best course of therapy for their patients.
On April 18, a team of researchers led by Lisa Rimsza, M.D., a pathologist and Director of the Mayo Clinic Molecular Diagnostics—Arizona Laboratory, launched a new genetic test, the Lymph3Cx, which distinguishes between the two types of lymphoma. The establishment of the test and their study results were published in the journal Blood.
Having a test like this available in a clinical laboratory setting can help physicians determine the correct classification of lymphoma to improve therapeutic decision-making for patient care. The test can also be used as a tool to support clinical trials.
“The Lymph3Cx test offers a glimpse into the biology happening inside the cells, painting a picture for what cannot be seen with a microscope, providing yet another piece of the diagnostic puzzle,” says Dr. Rimsza.
The Lymph3Cx test was validated in the Mayo Clinic Molecular Diagnostics —Arizona Laboratory and uses routinely available pathological specimens without requiring added invasive procedures. The turnaround time is typically just a few days, helping patients get the appropriate treatment quickly.
The Lymph3Cx test is considered a modular upgrade to the Lymph2Cx test launched by Mayo Clinic in 2016 with support from the Mayo Clinic Center for Individualized Medicine. Mayo Clinic was the first in the U.S. to offer the Lymph2Cx genetic test to help guide diagnosis and treatment of patients with diffuse large B-cell lymphoma, based on how the lymphoma started, assigning “cell-of-origin” groups using a 20-gene expression-based test. Since 2016, the Lymph2Cx test has been used to screen more than 150 Mayo Clinic patients in Arizona, Florida, and Rochester.
Diagnostic tests like the Lymph2Cx and Lymph3Cx are important for addressing the unmet needs of patients with cancer by providing an individualized approach to treatment. According to Dr. Rimsza, such tests help establish a prognosis, choose an appropriate therapy, and achieve the best outcome possible.