Examination of the relationship between chromosome abnormality in pituitary adenomas and tumor invasiveness by normal karyotype analysis and interphase fluorescence staining.

To study the potential relationship between chromosome abnormality and tumor invasiveness in pituitary adenomas. To use conventional R-band cytogenetic karyotype analysis and interphase fluorescence in situ hybridization using centromeric probe of chromosomes 8, 9, and 11 to detect chromosome abnormality in 30 cases of pituitary adenoma. All chromosomes except chromosomes 4, 16, and Y show significant variation between invasive and noninvasive pituitary adenomas. Chromosomes 8 and 12 display some type of numeric alteration in all endocrine subtypes of pituitary adenoma. Numeric alterations in chromosomes 9, 11, and 19 are more frequently detected in invasive pituitary adenomas compared with noninvasive tumors. Numeric alterations in chromosomes are common in all endocrine subtype pituitary adenomas. Furthermore, chromosome numbers are significantly different in invasive and noninvasive pituitary adenomas. On the basis of our study and literature review, we conclude that while chromosomes 8 and 12 may play important roles in the occurrence of pituitary adenomas, chromosomes 9, 11, and 19 may be specifically associated with invasiveness.