ABSTRACT
<p><b>OBJECTIVE</b>To investigate the cytogenetic characteristics of the various plasma cell dyscrasia using the CD138 MACS-FISH, to elucidate the application value of MACS-FISH in the genetic diagnosis of plasma cell dyscrasia, and to explore the standardization of FISH detection for plasma cell dyscrasia.</p><p><b>METHODS</b>A total of 232 patients with newly diagnosed plasma cell dyscrasia were collected, including 203 cases of MM, 24 cases of AL amyloidosis and 5 cases of MGUS, whose cytogenetic abnormalities were detected by MACS-FISH, and the differences of the positive detection rates of chromosome karyotype analysis, C-FISH and MACS-FISH in MM cytogenetic abnormality were compared. The sensitivity of C-FISH and MACS-FISH were analyzed and compared according to the proportion of bone marrow plasma cells. The correlation between the positive cell rates of C-FISH and MACS-FISH and the proportion of plasma cells were analyzed respectively. The differences in the clone size detected by C-FISH and MACS-FISH were compared.</p><p><b>RESULTS</b>The incidence of cytogenetic abnormality of MM, AL amyloidosis and MGUS detected by MACS-FISH were 85.9%, 62.5%, 60%, respectively. The incidence rate of MM cytogenetic abnormality detected by Chromosome karyotype analysis and C-FISH were 20.0% and 64.7%, respectively, which were significantly lower than that of MACS-FISH(P<0.001). The positive rate of 14q32 translocation, del(14q32), t(11;14), +17p13 and the coexistence of 2 and ≥3 kinds of cytogenetic abnormalities detected by MACS-FISH were significantly higher than that detected by C-FISH(P<0.05). When the plasma cell ratio was less than or equal to 5%, the positive detection rate of MACS-FISH was significantly higher than that of C-FISH (P=0.001), and there was no significant difference in different plasma cell proportion group of MACS-FISH. However, when the plasma cell ratio was less than or equal to 5%, the positive detection rate of C-FISH detection was significantly lower than that of the other 3 groups (P=0.013,P=0.001,P<0.001). The positive cell rates of all cytogenetic abnormalities in C-FISH group and +1q21 and 14q32 translocation in MACS-FISH group were significantly positively correlated with the proportion of plasma cells(P<0.05). The clone size of various cytogenetic abnormalities in MACS-FISH group were significantly higher than that in C-FISH group(P<0.001).</p><p><b>CONCLUSION</b>MACS-FISH may significantly enhance the detection rate of cytogenetic abnormalities in various plasma cell dyscrasia, and it can better reflect the cytogenetic abnormality of plasma cell dyscrasia and its clone size. MACS-FISH may be recommended as a standard method for the genetic diagnosis of plasma cell dyscrasia, the risk stratification of MM and SMM, as well as the genetic diagnosis and research of MGUS and AL amyloidosis.</p>
ABSTRACT
This study was purposed to evaluate the clinical significance of low molecular weight urinary proteins for diagnosis of early renal damage in patients with multiple myeloma (MM). Medical records of 278 patients with MM in Nanjing School of Clinical Medicine from January 2004 to May 2012 were analyzed retrospectively. These patients were divided into 3 groups: glomerular damage group (n = 143), tubular damage group (n = 114) and normal group (n = 21). The clinical and laboratorial data were compared among them. The correlations of urinary retinol-binding protein (RBP) or urinary N-acetyl-β-D-amino-glucosaminidase (NAG) with blood urea nitrogen (BUN), Scr, blood cystatin-C (Cys-C), clearance of creatinine (Ccr), 24 h protein uria and 24 h urine light chains were further analyzed, and the correlation of renal tubulointerstitial lesion scores with low molecular weight urinary proteins in 61 patients were also analyzed. The area under curve (ROC curve) was used to evaluate and compare the discrimination of urinary RBP and urinary NAG. The results showed that glomerular damage group had higher urinary RBP than tubular damage group. However, glomerular damage group had lower urinary NAG than tubular damage group. The two groups had higher urinary RBP and urinary NAG than that in normal group. Urinary RBP related positively to the level of Scr, BUN, Cys-C, 24 h proteinurias and related negatively to the level of Ccr. Urinary NAG related positively to the level of 24 h proteinurias, Ccr and related negatively to the level of Cys-C. Renal tubulointerstitial lesions were significantly correlated with urinary RBP, but weakly correlated with urinary NAG. It is concluded that urinary RBP significantly correlates with renal tubular damage. Compared with urinary NAG, urinary RBP can better assess the extent of renal damage, and has higher specificity.