CYTOGENETIC ANALYSIS OF 120 PRIMARY PEDIATRIC BRAIN-TUMORS AND LITERATURE-REVIEW

We report chromosome results from 108 pediatric central nervous system (CNS) tumors. From our data and those in the literature we found that (1) cerebellar and low-grade astrocytic tumors, including ganglioglio mas, are most often karyotypically normal; (2) supratentorial tumors w ere more frequently high-grade tumors that demonstrated a complex kary otype. Chromosome abnormalities were similar to those described in adu lt astrocytic tumors, namely, +7, 9p abnormalities, and -10; (3) primi tive neuroectodermal rumors (PNETs) were virtually always karyotypical ly abnormal with a high frequency of +7, -8, i(17q), and -22. PNETs wi th -22 may represent a subset of tumors; (4) typical choroid plexus pa pillomas showed a normal karyotype, atypical papillomas showed a hyper diploid karyotype (with +7, +12, and +20), choroid plexus carcinomas s howed a hyperhaploid karyotype; (5) a few ependymomas showed hyperdipl oidy or hypertetraploidy; (6) germ cell tumors showed complicated kary otypes; (7) monosomy 22 or 22q abnormalities appear to be a recurring finding in the malignant rhabdoid tumors; and (8) meningiomas showed - 22 or 22q abnormalities associated with a complex karyotype. In genera l, in pediatric CNS tumors the least differentiated neoplasms have the greatest number of cytogenetic abnormalities. However, our present mo rphologic criteria for tumor diagnosis do not always correlate with a consistent karyotype, and further study of pediatric brain tumor morph ology, site, behavior, and karyotype is required. (C) 1997 Elsevier Sc ience Inc., 1997.