The eye tumor biopsy must be taken before radiation
Once you have been diagnosed with primary uveal melanoma, if you choose to know your metastatic risk, a critical aspect is the timing involved in sampling your tumor. If you’re newly diagnosed, your doctor may already be discussing treatment of the eye tumor, in the majority of cases (more than 80%) with some form of radiation therapy
There is often a very short period of time between diagnosis and radiation treatment—and the tumor tissue sample required for DecisionDx-UM testing must be taken prior to radiation therapy.
Once tumor tissue has been exposed to radiation, the test’s ability to render meaningful results may be compromised. For this reason, the test cannot be run on radiated tissue. It is extremely important to have a discussion about the test with your treating doctor in the short window of time before radiation therapy (see “Talk to Your Doctor”).
Timing is not a critical issue if the treatment plan is enucleation, or removal of the eye. In this case, tissue can be collected by needle biopsy after the eye has been removed, or later, from the wax tissue block of the eye that is made following surgery, as is standard practice.