The WT1 test measures the expression levels of the WT1 gene, which is often elevated in certain types of cancer. It's used for diagnostic, prognostic, and monitoring purposes in various malignancies.

There are minimal risks associated with the test itself, as it's a simple blood draw. However, the results may have significant implications for the diagnosis and management of cancer, which should be discussed with a healthcare provider.

The normal range for WT1 gene expression can vary depending on the specific laboratory and the method used for testing. Generally, lower levels of expression are expected in healthy individuals compared to those with certain types of cancer.

Elevated levels of WT1 gene expression may suggest the presence of certain cancers, particularly kidney cancers like Wilms tumor, mesothelioma, and acute myeloid leukemia, among others.

The test typically requires a blood sample, although in some cases, other types of samples such as bone marrow or tissue biopsy specimens might be used.