Evaluation of the Sensitivity of Conventional Cytogenetic and Fluorescence in Situ Hybridization Methods for the Detection of Cytogenetic Abnormalities in Multiple Myeloma Patients: A Retrospective Study

The identification of genetic abnormalities in multiple myeloma (MM) patients is of particular importance in designing their treatment. Therefore, it is necessary to use diagnostic methods with high sensitivity to detect abnormalities. Conventional cytogenetic and fluorescent in situ hybridization (FISH) methods are commonly used to identify genetic abnormalities. So far, studies have been conducted to investigate the sensitivity of each of these methods alone; nonetheless, the present research aimed to assess and compare the sensitivity of two methods in identifying genetic abnormalities.

in this study, the sensitivity of Conventional cytogenetic and FISH methods for identifying genetic abnormalities in MM patients has been investigated and compared.

This retrospective study included 246 patients who were referred to Kariminejhad Center for the diagnosis of genetic abnormalities from 2009-2019. All patients were diagnosed based on diagnostic tests, as well as the approval of the relevant physician. The diagnosis of cytogenetic abnormality was made based on the two methods of conventional cytogenetic and FISH.

As evidenced by the obtained results, out of 246 patients examined by conventional cytogenetics, only 17.8% had abnormal karyotypes. While out of 67 patients examined by FISH, 64.1% had abnormal results. The results also pointed out that out of 50 patients with normal karyotypes, 31 cases had abnormal FISH results. Moreover, 25% of patients had hyperdiploidy (pseudodiploid or structural abnormality in 23 pairs of chromosomes), which was diagnosed by conventional cytogenetics. Furthermore, 40.90% of subjects had diploid abnormalities (pseudodiploid or structural abnormalities). In addition, FISH detected del 13q in 27.9% and t(11;14) IGH-CCND1 in 18.6% of patients, the most frequently observed compared to other abnormalities.

Considering that the variety of mutations and translocations is high in different parts of the world and new mutations are detected every day, the use of both methods together can help identify genetic disorders.