[Molecular genetic methods for the prognostic criteria in multiple myeloma]

Abstract

Routine cytogenetic and molecular genetic analysis of plasma cell malignancies, such as multiple myeloma, became widespread only recently. As the result of these investigations, it became clear that tumor cell karyotype is fundamental from the viewpoint of therapy selection and prognosis. It is worthwhile to distinguish hyperdiploid and nonhyperdiploid myeloma, while five separate prognostic groups (TCI-5) may be identified on the basis of immunoglobulin gene translocations and cyclin expression. Deletion of the q arm of chromosome 13 or amplification of region 1q21 (and the CKS1B gene) can identify further subgroups of poor prognosis and few therapeutic options. Meanwhile, tumors harboring translocation t(11;14) respond favorably to conventional chemotherapy and exhibit exceptionally good and long-lasting response to high-dose chemotherapy. Progression of the disease may coincide with complex translocations of the c-myc gene or deletions involving the p53 tumor-suppressor gene, spreading of ras-mutations. These events represent clonal evolution at great tumor cell mass and advanced disease, therefore, are only of secondary prognostic significance.