Cytogenetic abnormality in patients with multiple myeloma analyzed by fluorescent in situ hybridization

To analyze the fluorescent in situ hybridization (FISH) data and the association with clinical characteristics, therapy response, and survival time in patients with multiple myeloma.

We performed a retrospective review of patients with multiple myeloma from November 2010 to April 2014.

Cytogenetic abnormalities by FISH were detectable in 66% of patients. One cytogenetic abnormality, two cytogenetic abnormalities, and complex abnormalities were detectable in 21.2%, 51.5%, and 27.3% of cases, respectively. 1q21 amplification, t(4p16.3/14q32), and 17p deletion were observed in 69.7%, 30.3%, and 21.2% of cases, respectively. Total response rates (complete response [CR] + near CR + partial response) were 93.8% and 82.1%, respectively, in cytogenetic normality group and abnormality group. CR rates were 50% and 32.1%, respectively. Median overall survival (OS) time was 51 months and 24 months, respectively, in cytogenetic normality group and abnormality group (P<0.05). Median OS time was not significantly different between 1q21 amplification group and no 1q21 amplification group in patients with FISH abnormalities (P>0.05). Median OS time was not significantly different between t(4;14) group and no t(4;14) group in patients with FISH abnormalities (P>0.05). Seven patients of 17p deletion died in 2 years.

Multiple myeloma is characterized by a high occurrence of chromosomal aberrations. 1q21 amplification and t(4;14) are the most common abnormalities. Multiple cytogenetic abnormalities are frequently observed in the same one patient. The total response rate, CR rate, and OS time are worse in cytogenetic abnormal patients compared with cytogenetic normal patients. Patients with 17p deletion have a very poor prognosis. Future goals of therapy will be to achieve minimal residual disease, biomarkers, and genomic data, which might provide a better estimate of the depth of response to therapy and OS.