Deletion 1p in a low-grade chondrosarcoma in a patient with Ollier disease.

Ollier disease is an uncommon, nonhereditary developmental disorder affecting enchondral ossification. Cytogenetic analysis of low-grade chondrosarcoma in a patient with Ollier disease (multiple enchondromatosis) revealed an interstitial deletion, del(1)(p11p31.2), as the only chromosome abnormality. This is the first cytogenetic study of a chondrosarcoma in a patient with Ollier disease. Such patients are at risk of developing chondrosarcoma and, because del(1p) is frequent in chondrosarcoma, it is suggested that this cytogenetic finding is associated with early chondrosarcomatous transformation.

Translocation (6;10)(p21;q22) in uterine leiomyomas.

A translocation between chromosomes 6 and 10 was observed in two uterine leiomyomas. Translocation (6;10) may be important in the pathogenesis of a subgroup of uterine leiomyomas.

Trisomy 5 in long-term cultures from bone marrow of patients with solid tumors.

Long-term cultures of bone marrow from 15 cases diagnosed previously with primary solid tumors were analyzed cytogenetically. Of these cases, 10 had normal karyotypes and five had chromosomal abnormalities. Trisomy 5 was found in four cases, three with trisomy 5 as the only change and one with trisomy 5 and trisomy 12. These results suggest that trisomy 5 may be a nonrandom change associated with an in vitro or in vivo phenomenon.

Chromosome abnormalities in breast fibroadenomas.

Cytogenetic analysis of 25 breast fibroadenomas (FA) showed clonal chromosome alterations in three cases. Insertion (12;?) (q15;?) and deletion (2) (q14q31 or q32) were detected as a sole change in cases 1 and 3, respectively. Case 2 displayed the karyotype 45,XX,t(1;8;16)(q25;q23;q22-23), add (7)(p14), rea(15), -17. The present findings are discussed together with the reports on FA in the literature.

Cytogenetic findings in 19 malignant bone tumors.

BACKGROUND: The majority of karyotypes observed in osteosarcomas (OS) and chondrosarcomas (CS) are complex. Specific chromosomal abnormalities have not yet been characterized in either tumor except for a ring chromosome in parosteal OS. The purpose of this study was to determine recurrent chromosomal abnormalities and establish a possible correlation between the cytogenetic changes and the pathologic findings. METHODS: Ten OS and nine CS were cytogenetically analyzed. Tumor samples were obtained from patients having a resection or incisional biopsy. Cytogenetic study of short term cell cultures included harvesting and G-banding, which were performed by routine methodologies. RESULTS: Clonal abnormalities were observed in six OS and six CS. Modal chromosome numbers ranged from near diploid to near tetraploid in both types of tumors. The structural rearrangements observed in OS involved mostly chromosomes 1, 2, 6, 12, and 17. Nonreciprocal translocations were the most frequent event. Two OS had a single clonal abnormality involving 11p15 and 14q32, respectively. Double minute chromosomes were observed in three cases. In CS, the most frequent structural abnormalities were nonreciprocal translocations and deletions involving numerous chromosomes. Rearrangements of 1p together with other abnormalities were observed in four CS. CONCLUSIONS: The karyotypes were usually complex consisting of numerical and structural changes, particularly in high grade tumors. Rearrangements of 11p15 and 14q32 in OS and possibly 1p in CS were found as primary cytogenetic aberrations. Cytogenetic analysis in more cases of OS and CS together with molecular studies are necessary to characterize further the consistent genetic changes in these tumors.

Cytogenetic findings in 21 malignant melanomas.

Cytogenetic analysis was performed on 21 tumor samples of malignant melanoma to identify the presence of consistent chromosome abnormalities. Four cases had a normal karyotype, and 17 were cytogenetically abnormal. Numerical chromosome alterations were observed in 15 tumors: 12 were hyperdiploid and three were hypodiploid. The most frequent losses consisted of chromosomes 5, 9, 17 and Y. The structural abnormalities were usually complex, consisting mainly of nonreciprocal translocations and deletions affecting 1p, 1q, 3p, and 9p. This study adds further data to previously reported melanoma cases, confirming that chromosomes 1, 3, 6, and 9 are nonrandomly affected.

Deletion 7q22 in uterine leiomyoma. A cytogenetic review.

The cytogenetic patterns of uterine leiomyomas have been extensively investigated, and cases characterized by specific clonal changes have been documented in detail. In these tumors one of the cytogenetic changes frequently observed has been a del(7), particularly del(7)(q22), usually as a sole anomaly. This is confirmed by our experience and by reports in the literature. The fact that del(7) is one of the most common abnormalities in leiomyoma raises the question of its role in tumor development. The main purpose of this review is to analyze the above aspect and to interpret its possible meaning. Our findings on cytogenetic abnormalities of chromosome 7 in leiomyoma, together with those reported in the literature, are reviewed and discussed. A listing of the genes located at 7q22 is also presented.

Involvement of 10q22 in leiomyoma.

Cytogenetic investigation of uterine leiomyomas revealed a rearranged 10q22 present in nine tumors as a clonal change in most of the cells analyzed. These findings indicate that abnormalities involving chromosome 10 and, particularly 10q22, may characterize a cytogenetic subgroup of uterine leiomyomas.

Deletion of chromosome 13 in osteosarcoma secondary to irradiation.

The cytogenetic analysis of a radiation-induced osteosarcoma in a 31-year-old male is presented. Complex karyotypic changes with numerical and structural abnormalities, including a del(13)(q12.3q21.1), were observed. This deletion may indicate that loss of RB1 gene (locus in 13q14) may be involved in the development of radiation-induced osteosarcoma.

Chromosome 7 biclonality in uterine leiomyoma.

Biclonal chromosome complements in uterine leiomyoma have been reported occasionally. These previous studies reported the presence of two unrelated clones containing mainly t(12;14) and del(7). We describe four cases of typical leiomyoma displaying two clones, both involving chromosome 7 but with a different deletion in each of the two clones. For two of the tumors, the biclonal origin is the only possible explanation; for the remaining two cases, the origin of the two deleted chromosomes 7 could also be explained by clonal evolution, since the more proximal deletion on chromosome 7 in one clone appears to be subsequent to the deletion of the other clone. Even in these cases, however, the biclonal origin cannot be excluded completely. Despite the mechanism of origin, deletion of chromosome 7 is the most common cytogenetic abnormality in leiomyoma, indicating that loss of genetic material from the long arm of this chromosome is critical for tumor development.

Inversion (X)(p22q13) in a uterine leiomyoma.

We report a case of uterine leiomyoma which showed a karyotype 46,X,inv(X)(p22q13) as the only clonal change in most of the cells. A few cells had an additional del(7), though del(7) has been found to be a primary change in leiomyomas. These findings indicate that the abnormality involving the X chromosome and particularly Xp22 can be considered as a primary chromosomal abnormality. We discuss the findings together with few reports of cases involving chromosome X in leiomyomas.