Cytogenetic analysis of uterine leiomyoma: the size, histopathology and GnRHa-response in relation to chromosome karyotype.

Objective: The aim of this study was to elucidate the clinical characteristics of uterine leiomyomas having abnormal chromosome karyotype.

Study Design: A total of 394 myomas were obtained from 213 patients for cytogenetic analysis. The size (number of nodules=144), histopathology (n=302), and gonadotropin-releasing hormone analogue (GnRHa)-response (n=58) were investigated in relation to chromosome karyotype in myomas.

Results: 302 myomas from 166 patients were successfully karyotyped. A total of 21 myomas from 21 patients showed abnormal chromosome karyotype. The high frequencies of involved chromosomes 12, 14, 1, 7 were observed. The diameters of myomas with abnormal karyotype were significantly larger than those of myomas with normal karyotype. The frequency of the degeneration in myomas with abnormal karyotype was significantly higher than that with normal karyotype. The reduction rate in size of myomas by GnRHa treatments did not differ between the two types (karyotype normal versus abnormal) of nodules.

Conclusions: Chromosomally abnormal myomas were larger in diameter and showed a higher frequency of degeneration, suggesting that the cytogenetic background in uterine leiomyoma affects a tumor's growth potential.