Quade B J, Pinto A P, Howard D R, Peters W A, Crum C P
Department of Pathology, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115, USA.
Am J Pathol. 1999 Mar;154(3):945-50. doi: 10.1016/S0002-9440(10)65342-4.
Distinction of malignant uterine leiomyosarcomas from benign leiomyomas by morphological criteria is not always possible. Leiomyosarcomas typically have complex cytogenetic abnormalities; in contrast, leiomyomas have simple or no cytogenetic abnormalities. To understand better the biological distinction(s) between these tumors, we analyzed two other potential markers of genomic instability, loss of heterozygosity (LOH) and microsatellite instability. We examined archival materials from 16 leiomyosarcomas and 13 benign leiomyomas by polymerase chain reaction for 26 microsatellite polymorphisms. Markers were selected based on previous reports of cytogenetic or molecular genetic abnormalities in leiomyosarcomas or leiomyomas and surveyed chromosomes 7, 9, 10, 11, 12, 14, 15, 16, 18, 21, and X. LOH for markers on chromosomes 15, 18, 21, and X was infrequent in leiomyosarcomas (1 of 6 tumors for each chromosome) and not observed for markers on chromosomes 7, 9, 11, 12, 14, or 16. Interestingly, 8 of 14 (57.2%) informative leiomyosarcomas had LOH for at least one marker on chromosome 10 and involved both chromosomal arms in 45.5% (5 of 11). In contrast to leiomyosarcomas, LOH for chromosome 10 was not found in 13 benign leiomyomas. Microsatellite instability was found infrequently in leiomyosarcomas and not detected in leiomyoma. Clinicopathological features (eg, atypia, necrosis, and clinical outcome) did not appear to correlate with LOH for chromosome 10. In contrast to other chromosomes studied, LOH on chromosome 10 was frequent in leiomyosarcomas and absent in benign leiomyomas.
通过形态学标准区分恶性子宫平滑肌肉瘤和良性平滑肌瘤并非总是可行的。平滑肌肉瘤通常具有复杂的细胞遗传学异常；相比之下，平滑肌瘤具有简单的细胞遗传学异常或无细胞遗传学异常。为了更好地理解这些肿瘤之间的生物学差异，我们分析了基因组不稳定的另外两个潜在标志物，杂合性缺失（LOH）和微卫星不稳定性。我们通过聚合酶链反应检测了16例平滑肌肉瘤和13例良性平滑肌瘤的存档材料中的26个微卫星多态性。根据先前关于平滑肌肉瘤或平滑肌瘤细胞遗传学或分子遗传学异常的报道选择标志物，并检测7、9、10、11、12、14、15、16、18、21和X染色体。15、18、21和X染色体上标志物的LOH在平滑肌肉瘤中很少见（每条染色体6个肿瘤中有1个），而7、9、11、12、14或16号染色体上的标志物未观察到LOH。有趣的是，14例（57.2%）信息丰富的平滑肌肉瘤中有8例在10号染色体上至少有一个标志物发生LOH，45.5%（11例中有5例）涉及两条染色体臂。与平滑肌肉瘤相反，13例良性平滑肌瘤中未发现10号染色体的LOH。微卫星不稳定性在平滑肌肉瘤中很少见，在平滑肌瘤中未检测到。临床病理特征（如异型性、坏死和临床结局）似乎与10号染色体的LOH无关。与其他研究的染色体相比，10号染色体的LOH在平滑肌肉瘤中很常见，而在良性平滑肌瘤中不存在。
