Chandrika Sreekantaiah

Clonal chromosomal abnormalities in desmoid tumors. Implications for histopathogenesis.

Desmoid tumors (aggressive fibromatosis) are regarded as lesions of uncertain histopathogenesis. Cytogenetic analyses of 26 desmoid tumor specimens from abdominal or extraabdominal sites of 22 patients with or without Gardners syndrome (GS) showed clonal karyotypic abnormalities in 7 cases, random abnormalities in 14 cases, and striking telomeric fusion in 5 cases. Loss of chromosome Y, a reported feature of fibromatosis in penile and palmar locations, was detected as a clonal aberration in two patients. Additionally, involvement of 5q was observed in six patients, two of whom had GS. Clonal interstitial deletions of 5q were observed in three patients, one with and two without GS. These findings confirm a clonal and probable neoplastic origin for desmoid tumor and suggest that abnormalities of the Y chromosome and 5q may be important in the genesis of this neoplasm.

A recurring translocation, t(11;22)(p13;q11.2), characterizes intra-abdominal desmoplastic small round-cell tumors.

We report the cytogenetic analysis of two cases of intra-abdominal desmoplastic small round-cell tumor, one of which had a t(11;22)(p13;q11.2) translocation. The same translocation has previously been reported in two other cases analyzed cytogenetically, indicating that it could be a consistent abnormality characteristic of this rare tumor entity.

Cytogenetic findings in clear cell sarcoma of tendons and aponeuroses: Malignant melanoma of soft parts

Cytogenetic analyses of clear cell sarcomas from two patients are reported. Clonal numerical and structural abnormalities were detected in both specimens, with specific involvement of chromosomes 2 and 22 in each.

Nonrandom cytogenetic changes in leiomyomas of the female genitourinary tract:A report of 35 cases

Cytogenetic analysis of short-term cultures from 35 leiomyomas of the female genitourinary tract showed abnormal karyotypes in 14 cases. In 11 of 14 aberrant tumors, normal cells were also observed. Structural changes were most frequent, resulting in modal chromosome numbers in the diploid range. Our data confirm preferential breakpoint clusters at 7q, 12q14-15, and 14q23-24, mainly resulting from consistent, specific chromosome rearrangements such as t(12;14)(q14-15;q23-24) and del(7)(q21) or del(7)(q22q32). Together with previously published cases, we describe trisomy 12, ring chromosomes, and monosomy 22 as new additional recurrent findings in myomas. Statistical analyses of possible coherencies between tumor karyotype (abnormal versus normal) and clinicopathologic data, as well as age of the patients, menopausal status, and tumor size showed no correlations.

Cytogenetic findings in nine leiomyomas of the uterus

Chromosomal analysis of nine benign leiomyomas of the uterus after short-term culture showed karyotypic abnormalities in four cases. All four exhibited multiple chromosome changes, including three cases characterized by complex chromosome rearrangements involving a number of chromosomes. Among others, these rearrangements included a translocation between chromosomes 12 and 14 in one case, a deletion of chromosome 7q in two cases, and both del(7q) and a complex translocation involving chromosomes 12 and 14 in another case. These results confirm the involvement of chromosomes 7, 12, and 14 in leiomyomas and indicate that benign tumors can also be characterized by complex cytogenetic changes.

Trisomy 8 as a Nonrandom Secondary Change in Myxoid Liposarcoma

We report the cytogenetic findings in 5 cases of myxoid liposarcoma following short-term culture. In all 5 tumors a t(12:16)(q13:p11), characteristic of the myxoid form of liposarcoma, was observed. Trisomy 8 was present in two tumors as the only additional change and in a third in addition to other abnormalities. In the other two tumors the t(12:16) was present as the sole change. Three other myxoid liposarcomas with trisomy 8 as an additional aberration have been reported, suggesting that it could represent a non-random secondary event in these tumors.

Cytogenetic subtype involving chromosome 13 in lipoma: Report of three cases☆

We report three lipomas with rearrangements of chromosome 13. The karyotype of the tumors studied were 45,XX,-8,+der(8)t(8;13)(q22;q12),del(10)(p12),-13; 46,XY,del(13)(q12q22), and 46,XY,t(11;12)(q23;q13),del(13)(q12q22), respectively, revealing common involvement of band 13q12 in the rearrangement. Three other lipomas with aberrations of bands 13q12-q13 have been reported, suggesting that such tumors with abnormalities of chromosome 13 could represent a subgroup of lipoma in addition to those already reported with abnormalities of chromosomes 12q and 6p. The rearrangements of #13 in all these cases also involved loss of the band 13q14 to which the antioncogene associated with retinoblastoma and osteosarcoma is localized. Detailed clinical, histopathologic, and molecular studies should help to further characterize the various cytogenetically defined subgroups of lipoma.

An endometrial stromal sarcoma with clonal cytogenetic abnormalities

Cytogenetic analysis of a low-grade metastatic endometrial stromal sarcoma in a 58-year-old woman revealed translocations involving both homologues of chromosome 7 with chromosomes 13 and 17, respectively, and an interstitial deletion of the long arm of chromosome 11. The karyotype of the tumor was 46,XX,t(7;13)(q11.1;p13),t(7;17)(p21;q12),del(11)(q13q21).

Clonal chromosomal abnormalities in hemangiopericytoma.

We report the cytogenetic findings in nine hemangiopericytomas studied after short-term culture. Clonal chromosome abnormalities were present in four cases. One case had a simple translocation (12;19)(q13;q13.3) as the sole abnormality whereas complex and multiple chromosomal abnormalities involving almost all chromosomes in the complement characterized tumors from the three other cases.

Interstitial deletion of chromosome 11q in a pineoblastoma

A case of pineoblastoma with an interesting cytogenetic abnormality is reported. Chromosomal analysis of cultured cells from the tumor of a 10-week-old white male revealed an interstitial deletion of the long arm of chromosome 11, del(11)(q13.1q13.5). Tumors of the pineal region are relatively rare, and this is the first report of a pineoblastoma with del(11q).