1/55. ring chromosomes in a malignant mesenchymoma.We report, for the first time, the cytogenetic and molecular genetic constitution of a human mesenchymoma. As in several other soft tissue sarcomas, supernumerary ring and rod-shaped marker chromosomes were observed next to an otherwise normal diploid karyotype. Comparative genomic in situ hybridization and whole chromosome painting experiments revealed that chromosome 1q21-q25 and 12q14-q15 sequences were amplified, and that these sequences resided on the supernumerary marker chromosomes. We assume that, in this malignant mesenchymoma, the observed chromosomal anomalies may be associated with its well differentiated liposarcomatous component.- - - - - - - - - - ranking = 1keywords = liposarcoma (Clic here for more details about this article) |
2/55. dna ploidy alterations detected during dedifferentiation of periosteal chondrosarcoma.dna ploidy of a case with dedifferentiated periosteal chondrosarcoma was analyzed by dna cytofluorometry. The diagnosis of primary periosteal chondrosarcoma was made on the basis of the radiographic and histological findings. At 4 years after marginal resection, the tumor recurred locally and metastasized to various organs. The patient died of disease 2 years later. Histologically, there were two components, chondrosarcoma and malignant fibrous histiocytoma, in the recurrent and metastatic tumors. dna ploidy analysis of multiple samples revealed that the primary lesion was composed of many diploid cells with some tetraploid and octaploid cells, whereas in the dedifferentiated area, there were many aneuploid cells which were not recognized in any area of the primary tumors. This case illustrated that dna ploidy alteration of euploidy to aneuploidy is closely correlated with the process of dedifferentiation in chondrosarcoma.- - - - - - - - - - ranking = 774.39528573646keywords = dedifferentiated (Clic here for more details about this article) |
3/55. Molecular genetic characterization of both components of a dedifferentiated chondrosarcoma, with implications for its histogenesis.Dedifferentiated chondrosarcoma is defined as a high-grade, anaplastic sarcoma adjacent to a low-grade malignant cartilage-forming tumour. Controversy remains as to whether the anaplastic and cartilaginous components are derived from a common precursor cell, or whether they represent separate genotypic lineages (collision tumour). Both components of a case of dedifferentiated chondrosarcoma were therefore separately investigated by loss of heterozygosity (LOH) analysis, comparative genomic hybridization (CGH), dna flow cytometry, and p53 analysis. Both showed p53 overexpression and an identical somatic 6 bp deletion in exon 7 of p53. Combination of the CGH and LOH results revealed that both components had lost the same copy of chromosome 13. These results provide compelling evidence in this case for a common origin, instead of the 'collision tumour' theory. Certain genotypic alterations were not shared. The anaplastic component showed severe aneuploidy, LOH at additional loci, and amplification and deletion of several chromosome parts. In contrast, the cartilaginous component had lost chromosomes 5, 22, 17p and part of 16p and revealed an amplification of 17q. The LOH and CGH results further demonstrated that the two components had lost a different copy of chromosome 4. Thus, a substantial number of genetic alterations have occurred after the diversion of the two components, indicating that the separation of the two clones, derived from a single precursor, was a relatively early event in the histogenesis of this case of dedifferentiated chondrosarcoma.- - - - - - - - - - ranking = 2323.1858572094keywords = dedifferentiated (Clic here for more details about this article) |
4/55. Dedifferentiated chondrosarcoma with features of telangiectatic osteosarcoma.We describe a 44-year-old female with a known history of a solitary osteochondroma of the scapula followed on X-ray for five years. She then presented with a rapidly growing lump. Imaging studies confirmed the presence of an aggressive looking lesion. Excision was performed and pathology showed a dedifferentiated chondrosarcoma with features of a telangiectatic osteosarcoma.- - - - - - - - - - ranking = 387.19764286823keywords = dedifferentiated (Clic here for more details about this article) |
5/55. Dedifferentiated chondrosarcoma of the larynx.A 74-year-old man with a history of a chondroid lesion of the larynx noted an enlarging neck mass. Axial CT showed a large expansile lesion arising from the left thyroid cartilage. Multiple rings and arcs with relatively intact cortex indicated a chondroid lesion. Irregularity of the anterolateral margin abutted a prominent soft-tissue component. The specimen obtained from fine needle aspiration was suggestive of a malignant fibrous histiocytoma. After further resection, the final diagnosis was dedifferentiated chondrosarcoma. A new soft-tissue component or rapid growth of the mass can be indicative of a diagnosis of dedifferentiated chondrosarcoma.- - - - - - - - - - ranking = 774.39528573646keywords = dedifferentiated (Clic here for more details about this article) |
6/55. Parachordoma of the tibia: report of a rare case.We report a case of recurrent parachordoma of the left anterior tibial region in a 64-year-old male patient. The tumor was a periosteal tender mass, and, histologically, displayed vague nodules of spindle to rounded eosinophilic cells embedded in a myxoid matrix. Large vacuolated (physalphorouslike) cells were noted as in sacrococcygeal chordoma. This tumor should be differentiated from myxoid chondrosarcoma, myxoid liposarcoma, chondromyxoid fibroma, and metastatic chordoma. The presence of physaliphorous cells in the tumor with positive immunoreactions caused by cytokeratin rules out the diagnosis of another myxoid tumor. The differential diagnosis from metastatic chordoma is basically made by clinicians. Even though parachordoma is usually regarded as a benign soft tissue neoplasm, two recurrences occurred in our case. Since the reported cases, including ours, have diverse clinical courses, it is essential to follow-up the patient carefully.- - - - - - - - - - ranking = 1keywords = liposarcoma (Clic here for more details about this article) |
7/55. Fine-needle aspiration of dedifferentiated chondrosarcoma of the larynx.We present a case of dedifferentiated chondrosarcoma of the larynx in which the dedifferentiated component was initially diagnosed by fine-needle aspiration (FNA). The patient was a 74-yr-old man who presented with difficulty breathing and an anterior neck mass. A CT scan demonstrated a 4.5-cm cartilaginous lesion involving the left thyroid cartilage, with an anterior soft-tissue component. Nine years prior, the patient had an incomplete resection of a low-grade chondrosarcoma at the same site. FNA was performed on the current lesion, demonstrating a high-grade spindle-cell sarcoma with a storiform pattern. The cytomorphology together with immunocytochemistry and electron microscopy were diagnostic of malignant fibrous histiocytoma (MFH), and synthesis of the clinical, radiographic, and cytomorphologic features resulted in a diagnosis of dedifferentiated chondrosarcoma. The cytologic diagnosis was histologically confirmed by laryngectomy. Although rare, dedifferentiated chondrosarcoma should be included in the differential diagnosis of high-grade sarcomas of bone and cartilage assessed by FNA.- - - - - - - - - - ranking = 3097.5811429458keywords = dedifferentiated (Clic here for more details about this article) |
8/55. Cutaneous metastases as initial manifestation of dedifferentiated chondrosarcoma of bone. An autopsy case with review of the literature.Metastases of chondrosarcoma to the skin are uncommon. We report a case of dedifferentiated chondrosarcoma that manifested as cutaneous metastases and had an outcome of three weeks. A 69-year-old male presented with two cutaneous nodules, one in the chest and other in the inguinal area. The punch biopsy of the latter showed a poorly differentiated mesenchymal metastatic tumor. Shortly before death, an X-ray revealed a proximal epiphyseal lesion in the right humerus, radiographically interpreted as chondrosarcoma. The autopsy showed this lesion to be a dedifferentiated chondrosarcoma whose nonchondroid mesenchymal part was akin, histologically and immunohistochemically, to the cutaneous metastases. While ten previous reports of chondrosarcoma metastatic to the skin are known, we believe that this is the first case to report the cutaneous metastases of the dedifferentiated variety. Furthermore, skin metastasis preceding the diagnosis of chondrosarcoma has not been previously reported. The fact that one part of this kind of tumor can be highly undifferentiated or, else, differentiated along lines not usually reminiscent of bone tumors, can make the diagnosis of such cases extremely difficult. Most chondrosarcomas metastatic to the skin arise in bones of the extremities, including the hand. The most common type of tumor is conventional chondrosarcoma. These metastases can be either single or multiple with a slight predilection for the head and neck region. Most patients die in a mean time of 6 months after the appearance of cutaneous metastases.- - - - - - - - - - ranking = 2710.3835000776keywords = dedifferentiated (Clic here for more details about this article) |
9/55. 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 = 2710.3835000776keywords = dedifferentiated (Clic here for more details about this article) |
10/55. 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 = 387.19764286823keywords = dedifferentiated (Clic here for more details about this article) |
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