PP120 Fluorescent In Situ Hybridization (FISH) Vs Conventional Cytogenetic (CC) For Detecting High-Risk Genetic Mutations In Multiple Myeloma

IntroductionThe Revised International Staging System (R-ISS) International Myeloma Working Group (IMWG) recommends a minimal panel to detect high-risk cytogenetics (del17p, t[4;14], t[14;16]) for patients with multiple myeloma (MM). In the Brazilian Public Health System, the use of FISH is currently authorized for rare diseases only, not including MM. In 2021, the Brazilian National Committee for Health Technology Incorporation, with the purpose of broadening the use of FISH to MM patients, requested a review to be undertaken by the Health Technology Assessment Center of University of Campinas’ Teaching Hospital. This study presents the results of a meta-analysis comparing FISH vs CC to the detection of the above-mentioned aberrations in MM patients.MethodsOn 25 June 2021, a pre-structured search on four databases (Embase, MEDLINE, Cochrane and LILACS) was performed to identify studies comparing FISH and CC results in MM patients for the detection of high-risk cytogenetics (del17p, t[4;14], and t[14;16]) in MM patients’ bone marrow samples. Study selection, risk of bias assessment, data extraction (frequency of positive tests) and quality of evidence assessment were performed by two independent researchers. Conflicts were solved in agreement meetings with a third researcher. Meta-analysis was performed using frequency of positives to obtain Risk Difference (RD), a surrogate measure of the surplus positive tests between FISH and CC.ResultsFrom a total of 1346 rendered entries, 11 studies were selected. Only observational studies were available. These studies presented an overall high risk of bias (QUADAS-2). A total of 781 patients were assessed (653 evaluated by FISH and 719 by CC). Meta-analysis results showed that, for t(4;14) FISH detected 12 percent more samples (RD:0.12 [95% confidence interval (CI):0.06-0.19]). For t(14;16), FISH detected 0.42 percent more samples (RD:0.00 [95%CI:-0.01-0.02]). And for del17p, FISH detected 1.6 percent more samples (RD:0.12 [95%CI:0.04-0.20]).ConclusionsFISH appears to be more effective than CC on the detection of t(4;414) and del17p aberrations, and can be a useful tool in hematology practice. The results of t(14;16) presented non-superiority, probably due to the low frequency of this aberration.