Sawyer J R, Chadduck W M, Keltzel M
Department of Pathology, Arkansas Children's Hospital, Little Rock 72202.
Cancer Genet Cytogenet. 1990 Jul 1;47(1):89-94. doi: 10.1016/0165-4608(90)90267-e.
A patient previously reported to have Ewing's sarcoma showed a t(11;22) (q23;q11) and spontaneous expression of fra(11)(q23) [1]. Subsequent review of pathologic specimen indicated, however, that it was an Askin's tumor. Reciprocal translocations of chromosomes 11 and 22 are the most common cytogenetic abnormalities in Ewing's sarcoma and the related Askin's tumor. After radiation therapy of a residual metastatic brain lesion, subsequent studies of the recurrent brain tumor indicated the presence of the original translocations as well as five new reciprocal translocations and two deleted segments (9p-, 10p-). The new chromosome abnormalities were consistently found, indicating that progression of the tumor was clonal. The newly observed clonal aberrations were considered secondary in nature. A relationship between craniocerebral irradiation and development of brain tumors has been reported in several studies, but the mechanism for tumor induction has not yet been elucidated. It is important that the role of radiation therapy in the evolutionary process of chromosomal changes be studied in a large group of similar cases.
一名先前报告患有尤因肉瘤的患者显示出t(11;22)(q23;q11)以及fra(11)(q23)的自发表达[1]。然而，随后对病理标本的复查表明，它是一种阿氏瘤。11号和22号染色体的相互易位是尤因肉瘤及相关阿氏瘤中最常见的细胞遗传学异常。在对残留的脑转移病灶进行放射治疗后，对复发性脑肿瘤的后续研究表明存在原始易位以及五个新的相互易位和两个缺失片段(9p-、10p-)。新的染色体异常持续被发现，表明肿瘤进展是克隆性的。新观察到的克隆畸变被认为本质上是继发性的。几项研究报告了颅脑照射与脑肿瘤发生之间的关系，但肿瘤诱导机制尚未阐明。重要的是，要在一大组相似病例中研究放射治疗在染色体变化进化过程中的作用。
