Brynes R K, Swayne D, McCourty A, Dosik G M, Traweek S T, Slovak M L
Division of Pathology, City of Hope National Medical Center, Duarte, Calif 91010-0269.
Arch Pathol Lab Med. 1994 Dec;118(12):1196-200.
Trisomy 8 is the most common hyperdiploid numerical chromosomal abnormality that is found in myelodysplastic syndromes (MDSs). We explored the utility of combining fluorescence in situ hybridization interphase cytogenetics with routine morphologic analysis to characterize cases for which signs and symptoms were suggestive of MDS in which dysplastic changes were insufficient for a definitive diagnosis. Hybridization with a chromosome 8-specific centromeric probe was performed on bone marrow smears that were obtained from four patients with cytogenetically documented trisomy 8 and hematopoietic cell atypia that was suggestive but not diagnostic of MDS. Signals that corresponded to trisomy 8 were detected in 14.6% to 32.2% of the cells (detection threshold of trisomic clone, 5.0%). The conditions of two patients have remained hematologically stable with no disease progression, and these two patients are now considered to have refractory anemia. The conditions of the other two patients rapidly progressed to morphologically recognizable MDSs. This study demonstrates that the detection of trisomy 8 by fluorescence in situ hybridization can provide useful supplemental information in bone marrow specimens with morphologic changes that are suggestive of but not sufficient for a diagnosis of MDS. It should prove to be useful when standard cytogenetic analysis has not been performed or when it is not readily available.
8号染色体三体是骨髓增生异常综合征（MDS）中最常见的超二倍体数目染色体异常。我们探讨了将荧光原位杂交间期细胞遗传学与常规形态学分析相结合的实用性，以对那些体征和症状提示为MDS但发育异常改变不足以做出明确诊断的病例进行特征描述。对4例经细胞遗传学证实为8号染色体三体且存在提示但不能诊断为MDS的造血细胞异型性的患者的骨髓涂片，进行了与8号染色体特异性着丝粒探针的杂交。在14.6%至32.2%的细胞中检测到了与8号染色体三体相对应的信号（三体克隆的检测阈值为5.0%）。两名患者的病情在血液学上保持稳定，无疾病进展，这两名患者目前被认为患有难治性贫血。另外两名患者的病情迅速进展为形态学上可识别的MDS。本研究表明，通过荧光原位杂交检测8号染色体三体可为骨髓标本中形态学改变提示但不足以诊断MDS的情况提供有用的补充信息。当未进行标准细胞遗传学分析或无法轻易获得该分析时，它应会被证明是有用的。
