Dr. Fonseca on FISH Testing in Patients With Myeloma

Rafael Fonseca, MD, hematologist, Mayo Clinic, discusses the use of fluorescence in situ hybridization (FISH) testing in diagnosing patients with myeloma.

By definition, every patient with myeloma will have genetic abnormalities. High risk is determined by FISH, but many people are not using FISH correctly, says Fonseca. They’re sending the bone marrow without consideration for sorting of the cells, or otherwise marking of the cells. Pathology labs are looking at the nuceli of the bone marrow which doesn’t provide the right information. The correct information is important for physicians to think about high-risk markers, subsequent maintenance strategies, and counseling approaches.

Induction chemotherapy is a highly effective treatment, but leaves no viable plasma cells behind. Therefore, physicians who see patients who have received 1 or 2 cycles of induction therapy have lost the opportunity to look at plasma cells following treatment. Consequently, there is no opportunity to know if a FISH report is normal or not, he says.