van der Velden Vincent H J, Hoogeveen Patricia G, Pieters Rob, van Dongen Jacques J M
Department of Immunology, Erasmuc MC, Erasmus University Medical Center, the Netherlands.
Br J Haematol. 2006 May;133(4):382-8. doi: 10.1111/j.1365-2141.2006.06056.x.
Minimal residual disease (MRD) diagnostics are used for risk group stratification in several acute lymphoblastic leukaemia (ALL) treatment protocols. It is, however, unclear whether MRD is homogeneously distributed within the bone marrow (BM) and whether this affects MRD diagnostics. We, therefore, analysed MRD levels in 141 paired BM samples (two independent punctures at different locations) from 26 ALL patients by real-time quantitative polymerase chain reaction (PCR) analysis of immunoglobulin and T-cell receptor gene rearrangements. MRD levels were comparable in 112 paired samples (79%), whereas two samples (both taken at day 15) had MRD levels that differed more than threefold. In the remaining 27 paired samples, MRD could be quantified or detected in one sample only. In four patients, MRD-based risk group classification was dependent on the site of BM puncture. Repetition of MRD analyses using 10-fold replicates instead of triplicates resolved most differences. In conclusion, MRD levels in paired BM samples were highly comparable, indicating that it is sufficient to analyse MRD in a single sample only. Nevertheless, MRD-based risk group classification can differ between paired BM samples, mainly because of variation below the quantitative range of the PCR assay rather than to a different distribution of leukaemic cells within the BM.
微小残留病（MRD）诊断用于多种急性淋巴细胞白血病（ALL）治疗方案中的风险组分层。然而，尚不清楚MRD在骨髓（BM）中是否均匀分布以及这是否会影响MRD诊断。因此，我们通过对免疫球蛋白和T细胞受体基因重排进行实时定量聚合酶链反应（PCR）分析，检测了26例ALL患者141对骨髓样本（不同位置的两次独立穿刺）中的MRD水平。112对样本（79%）的MRD水平相当，而两个样本（均在第15天采集）的MRD水平差异超过三倍。在其余27对样本中，仅在一个样本中可定量或检测到MRD。在4例患者中，基于MRD的风险组分类取决于骨髓穿刺部位。使用10倍重复而非3倍重复进行MRD分析可解决大多数差异。总之，配对骨髓样本中的MRD水平高度可比，表明仅分析单个样本中的MRD就足够了。然而,基于MRD的风险组分类在配对骨髓样本之间可能不同，主要是因为低于PCR检测定量范围的变异，而非白血病细胞在骨髓中的不同分布。
