1/21. mutation of p53 with loss of heterozygosity in the osteosarcomatous component of a dedifferentiated chondrosarcoma.We investigated a dedifferentiated chondrosarcoma of a 61-year-old woman with an osteosarcomatous high-grade component for p53 alteration. The low-grade cartilaginous and the high-grade osteosarcomatous components of the tumor were macrodissected and evaluated separately by immunohistochemistry and molecular biology. We used PCR-SSCP analysis and direct sequencing to screen exons 4-8 for p53 mutations. The p53 intron 1-polymorphism was investigated for loss of heterozygosity. A functionally relevant p53 missense mutation in codon 193 of exon 6 (A-to-T transversion) with loss of wild-type allele was detected only in the dedifferentiated component. Using the monoclonal antibody DO-1, immunohistochemistry failed to show p53 overexpression. This evidence of p53 mutation may be regarded as at least a co-factor that "switched" the preexisting low-grade conventional chondrosarcoma to a highly malignant dedifferentiated tumor.- - - - - - - - - - ranking = 1keywords = dedifferentiated (Clic here for more details about this article) |
2/21. Dedifferentiated clear cell chondrosarcoma.Dedifferentiation, a change in the histologic character and clinical behavior of a tumor to a more immature and aggressive one, occurs in approximately 11% of all chondrosarcomas. The original lesion is usually a low-grade chondrosarcoma. Clear cell chondrosarcoma is a rare cartilaginous tumor of low-grade malignancy with a preference for the ends of long bones. It is usually curable by resection. recurrence commonly follows inadequate surgery, and metastases to lung, brain, and bones can develop. However, dedifferentiation has not yet been described in association with clear cell chondrosarcoma. Three patients are described who were initially diagnosed as having clear cell chondrosarcoma of the femur. Two were treated with en bloc resection for a clear cell chondrosarcoma. One of these had an undifferentiated sarcoma in a local recurrence after 6 years. In the second, metastasis of the clear cell chondrosarcoma developed 5(1/2) years after surgery; autopsy revealed undifferentiated sarcoma in the lung, heart, and lumbar spine. The third patient had dedifferentiated clear cell chondrosarcoma at the time of resection following the biopsy diagnosis of clear cell chondrosarcoma. All three died with metastatic disease. These three patients represent three different manifestations of dedifferentiation-at initial diagnosis, at recurrence, and at metastasis. To our knowledge, this is the first description of dedifferentiation occurring in clear cell chondrosarcoma.- - - - - - - - - - ranking = 0.14285714285714keywords = dedifferentiated (Clic here for more details about this article) |
3/21. Chromosomal changes in a dedifferentiated chondrosarcoma: a case report and review of the literature.The chromosome abnormalities observed in a dedifferentiated chondrosarcoma are reported. A new molecular cytogenetic technique, spectral karyotyping, was used to identify and confirm structural rearrangements in this case. A review of the literature revealed that nine cases have been reported, in eight of which a complete description of the cytogenetic abnormalities was described. Structural aberrations were most frequently reported in chromosomes 1 and 9, and chromosomes 7 and 19 were most frequently observed to be involved in numerical aberrations (trisomy and tetrasomy). In chondrosarcomas, structural aberrations in chromosomes 1 and 9 and trisomy or tetrasomy of chromosome 7 are among the more frequently observed aberrations.- - - - - - - - - - ranking = 0.71428571428571keywords = dedifferentiated (Clic here for more details about this article) |
4/21. Primary liposarcoma of bone.A case is presented of a rare primary liposarcoma of bone localized to the major trochanter of the left femur of a 52-year-old female. Despite combined treatment with curettage and irradiation with a total dose of 4,500 rad the neoplasm showed rapid invasive growth with destruction of the bone, spread to the iliac fossa and outgrowth through the operation wound. Approximately 5 months after admission the patient succumbed due to widespread metastases in the lungs, liver and left kidney. The histopathology, clinical course and treatment of this rare neoplasm of the bone are discussed.- - - - - - - - - - ranking = 0.13788020653712keywords = liposarcoma (Clic here for more details about this article) |
5/21. Genetic and epigenetic alterations in tumor progression in a dedifferentiated chondrosarcoma.In this case of a dedifferentiated chondrosarcoma, we searched for genetic or epigenetic alterations in both components of the tumor, the low grade chondroblastic component, and the high grade osteosacomatouscomponent. To date, only little is known about aberrant patterns of dna methylation in chondrosarcomas. microdissection was used as a valuable method for clearly separating the tissues. We examined CpG island methylation of 8 tumor suppressor genes and candidate tumor suppressor genes, which are involved in different pathways: cell cycle (p21WAF1, p16INK4, p14ARF), apoptosis (DAPK, FHIT), dna repair (hMLH1), and cell adherence (E-Cadherin). We found p16INK4 and E-cadherin promotor methylation in the low grade chondroid compartment of the dedifferentiated chondrosarcoma. P16INK4, FHIT, and E-cadherin were methylated in the highly malignant osteosarcomatous compartment of the tumor. Earlier investigations of this chondrosarcoma showed p53 mutation and p53-LOH in the anaplastic component. As shown in this case, it was accompanied by Rb-LOH. Early methylation of p16IK4 and E-cadherin in the chondroid compartment could point to the monoclonal origin of demonstrated dedifferentiated chondrosarcoma. Further alterations, as shown in p53, Rb and FHIT, are responsible for the "switch" to a high grade anaplastic sarcoma.- - - - - - - - - - ranking = 1keywords = dedifferentiated (Clic here for more details about this article) |
6/21. Solitary bone metastasis from myxoid liposarcoma.BACKGROUND: Extrapulmonary metastasis is more common in liposarcoma than in other soft tissue sarcomas. However, osseous metastases are rare. CASE REPORT: We report the case of a 61-year-old woman with a solitary histologically proven bone metastasis of the right femur from primary myxoid liposarcoma of the left thigh. In September 2000 resection of the primary tumor was performed. histology showed a high-grade liposarcoma with round cell differentiation. Postoperative radiotherapy with 60 Gy was performed. In a follow-up MRI examination 11 months after initial diagnosis, a suspicious formation in the marrow space of the right proximal femur was detected. CT-guided biopsy was performed and histology showed a metastasis from liposarcoma. PET examination confirmed the metastasis as solitary. curettage of the metastasis was performed followed by radiotherapy with 60 Gy. The patient was without evidence of disease in the last follow-up. CONCLUSIONS: No standard treatment exists for the management of solitary extrapulmonary metastases from soft tissue sarcoma. Interdisciplinary cooperation is advised and the therapy concept should be chosen individually.- - - - - - - - - - ranking = 0.22060833045939keywords = liposarcoma (Clic here for more details about this article) |
7/21. Ring chromosome in parosteal osteosarcoma. Clinical and diagnostic significance.In this study, two specimens of a parosteal osteosarcoma, a rare primary bone neoplasm comprising only 3-6% of all osteosarcomas, were cytogenetically analyzed utilizing standard techniques. In contrast to the complex karyotypes previously reported in osteosarcoma, this particular histologic subtype was characterized by a single chromosomal aberration, a ring chromosome. ring chromosomes have been described as characteristic for two other low-grade malignant mesenchymal neoplasms, well-differentiated liposarcoma and dermatofibrosarcoma protuberans. We propose that the observation of a ring chromosome in osteosarcoma also correlates with a low-grade malignant potential.- - - - - - - - - - ranking = 0.027576041307424keywords = liposarcoma (Clic here for more details about this article) |
8/21. Case report 679. Central low-grade osteosarcoma with foci of dedifferentiation.An infrequently encountered case of well-differentiated CLOS containing dedifferentiated tumor foci in a 28-year-old Japanese man is reported. The patient died from widespread metastases with a microscopic appearance identical to the anaplastic dedifferentiated lesions of the original tumor. This is, to our knowledge, the first report of a case of CLOS with dedifferentiation at the time of initial surgery. The literature concerning CLOS was reviewed and the diagnostic features of CLOS discussed.- - - - - - - - - - ranking = 0.28571428571429keywords = dedifferentiated (Clic here for more details about this article) |
9/21. Pleomorphic ("dedifferentiated") chondrosarcoma. Report of a case initially examined by fine needle aspiration biopsy.Fine needle aspiration (FNA) biopsy of a predominantly radiolucent, destructive lesion of the right distal femoral metaphysis of a 69-year-old man produced smears containing spindle-shaped cells with cytologic features consistent with a malignant fibrous histiocytoma. This initial diagnosis was supported by immunoperoxidase staining, which was strongly positive for vimentin and alpha-1-antichymotrypsin, focally positive for S-100 protein and negative for desmin, muscle-specific actin, keratin, carcinoembryonic antigen and epithelial membrane antigen. Subsequent surgical resection revealed a lesion with a predominance of malignant fibrous histiocytoma-type regions; however, focal microscopic areas contained a low-to-medium-grade cartilaginous component. The final diagnosis rendered was thus pleomorphic or so-called "dedifferentiated" chondrosarcoma. This rare lesion should be included in the differential diagnosis of malignant spindle-cell lesions of bone assessed by FNA biopsy.- - - - - - - - - - ranking = 0.71428571428571keywords = dedifferentiated (Clic here for more details about this article) |
10/21. Malignant transformation in bone lipomas.This report presents four cases of presumed malignant transformation within intraosseous lipomas, one occurring in a stage I lesion and three in stage III lesions, according to my classification. These lesions demonstrated radiologic and histologic features of benign lipomas together with histologic fields of either malignant fibrous histiocytoma or liposarcoma. In two of the three patients who were followed up, the tumors were fatal despite amputation. Malignant transformation of a lipoma should be suspected when rapid bone destruction is seen in a stage I radiolucent lipoma. Malignant transformation of stage III lipomas could be mistaken for malignant transformation within bone infarcts.- - - - - - - - - - ranking = 0.027576041307424keywords = liposarcoma (Clic here for more details about this article) |
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