Prognostic Significance of Chromosome 13q14 Deletion and Expression of CD19, CD28 and CD117 in Multiple Myeloma

Abstract

MM is a neoplastic PC disorder that ischaracterized by clonal proliferation of malignant PCsin the BM microenvironment, M protein in the blood or urine, and associated organ dysfunction. It accounts for approximately 1% of all cancers and 10% of hematologic malignancies.The disease is slightly more common in men and in African Americans. The diagnosis of MM requires 10% or more clonalPCs on BM examination or a biopsy proven plasmacytoma andevidence of end-organ damage (hypercalcemia, renal insufficiency, anemia, or bonelesions i.e. CRAB) that is felt to be related to the underlying PC disorder.Treatment, although notcurative, is intended to control the disease and minimize its end-organ effects. The natural history of MM is heterogeneous with survivaltimes ranging from a few weeks to >20 years. Analysis ofprognostic factors is essential to compare outcomes within andbetween clinical trials. Prognosis in MM depends on host factors (age, performancestatus, and comorbidities),disease stageandaggressiveness together with response to therapy. Staging ofMM using the Durie–Salmon staging or the ISS provides prognostic information but is not helpful in making therapeutic choices. In the context of cytogenetics and prognosis inMM, deletions of 13q14 were shown to be an unfavorable prognostic variable whendetected by interphase FISH. It was reported that the loss of 13q14is not solely an independent prognostic factor, however, its prognostic value is attributed to its associationwith other cytogenetic abnormalities. Recent advances in flow cytometry have permittedmore specific and sensitive evaluations of PCpopulations.One of the advantages of multiparametericflowcytometry is the generation and identificationof markers that allow the unequivocal identification ofPCs among other hematopoietic cells, and the identification of aberrant PC phenotypesthat help to discriminate between normaland neoplastic PCs.Moreover, several marker combinations, particularly that of CD117and CD28, in addition to CD19, show promise in predicting outcome for MM. In light of that, the aim of this study was to evaluate the prognostic significance of del13q14 together withCD19, CD28 and CD117 expression in PCsas regards their impact on OS as well as clinical outcome of the newly diagnosed MM patients.