Complex Karyotypic Changes, Including Rearrangements of 12q13 and 14q24, in Two Leiomyosarcomas Mef Nilbert, Nils Mandahl, Sverre Heim, Anders Rydholm, GOran Helm, Helena Will,n, Bo Baldetorp, and Felix Mitelman ABSTRACT: Cytogenetic investigation of short-term cultures from two leiomyosarcomas revealed com- plex karyotypic changes in both cases. The first tumor, a subcutaneous leiomyosarcoma of the knee, had the karyotype 70-80,XY,+X,+Y,+l,+l,+2,+2,+3,+3,+4,+4,+7,+7,+8,+8, + 9, +10, +15, +15, +16, +16, +18, +19, + 20, + 21, + 21, + 22, + 22,t(?;5)(5;21)(?;q35p11;q11), t(?;5)(5;21)(?;q35pl 1;ql 1), + del(11)(q22),der(13)t(12;13)(q13;q22),der(14)t(9;14)(pl 1;pl 1), + 14p+, + t(20;?)(q13;?), +t(20;?)(q13;?), + 2 mar. A polyploidized clone with 120-150 chromo- somes was also abserved. DNA flow cytometry revealed only one abnormal peak, corresponding to a DNA index of 1.76. The other tumor, a uterine leiomyosarcoma, had the karyotype 61-67, X, - X , + 1, + 3, + 5, + 6, + 7, + 8, + 9, + 12, + 13, + 15, + t(1;1)(p32;q32), + der(1)t(1 ;8)(p 13;q 11), + del(2)(p 11), + del(2)(q22), + del(2)(q22), + del(3)(p13), + i(5p),t(8;14)(q24;q24), + der(8)t(8;14) (q24;q24), + del(10)(p12),der(11)t(11;15)(p15;q11),t(16;?)(pl 3;?),t(16;?)(q24;?),der dic(17) (17pter-*cen-*l 7q25::hsr::l 7q25-*cen-*17pter), + t(19;?)(p13;?), + der dic(20)(2Opter--*cen--~ 20q12::hsr::20q12--~cen-~20pter), + mar. The DNA index was 1.59. The finding in these leiomyo- sarcomas of rearrangements of the same regions of chromosomes 12 and 14 that are involved in the tumor-specific t(12;14)(q14-15;q23-24) of uterine leiomyoma indicates that the same genes in 12q and 14q might be important in the pathogenesis of benign and malignant smaoth muscle tumors. INTRODUCTION Leiomyosarcoma represents one tenth of soft tissue sarcomas and one fourth of uterine sarcomas [1, 2]. Cytogenetic studies of leiomyosarcoma have shown chromosome anomalies in only 17 tumors from different organs [3-14]. The karyotypic picture is diverse; no tumor-specific abnormalities have been identified. We present two leiomyosarcomas, one subcutaneous and one uterine, both with complex clonal chro- mosome anomalies. From the Departments of Clinical Genetics (M. N, N. M., S. H., F. M.), Orthopedics (A. R.), Clinical Pathology (H. W.), and Oncology (B. B.), University Hospital, Lund, and the Department of Gynecology (G. H.), Central Hospital, Helsingborg, Sweden. Address reprint requests to: Mef Nilbert, Department of Clinical Genetics, Lund University Hospital, S-221 85 Lund, Sweden. Received October 24, 1989; accepted January 8, 1999. 217 © 1990 Elsevier Science Publishing Co., Inc. Cancer Genet Cytogenet 48:217-223 (1990) 655 Avenue of the Americas, New York, NY 18010 0165-4608/90/$03.50