1/20. Fine structure of a radiation-induced osteogenic sarcoma.An osteogenic sarcoma arose in the right orbit of a 7-year-old boy some 5 years after the right orbit had been treated by four courses of radiotherapy (total dose approximately 13,000 rads) for a multicentric retinoblastoma. death occurred 6 months after the orbital tumor was first detected. Study of the orbital tumor by electron microscopy revealed a cell population of varied morphology in which two main types were identified. In one group, the cells were large with radiolucent cytoplasm, which contained long branching segments of rough endoplasmic reticulum. In the second group, the cells were smaller with irregular nuclei and an electron-dense cytoplasm, which contained short segments of dilated rough endoplasmic reticulum and numerous mitochondria. The first group of cells closely resembled osteoblasts, while the second group had some features of osteoclasts or their percursors. The branching processes of the tumor cells were separated by an amorphous ground substance, which contained collagen-like fibrils and hydroxyapatite crystals. Crystal deposition was in some instances in close relation to extracellular membrane-bound vesicles.- - - - - - - - - - ranking = 1keywords = membrane (Clic here for more details about this article) |
2/20. Extraskeletal osteosarcoma of the scalp.A rare case of extraskeletal osteosarcoma of the scalp in a 56-year-old woman is described. At presentation she was found to have an 8-cm diameter, tender, firm, exophytic scalp tumor. MRI scan confirmed absence of underlying skeletal origin and showed extension along the subcutaneous plane. The tumor was excised and the patient received post-operative chemotherapy. Histologically, the tumor showed classical features of an osteogenic osteosarcoma with focal fibroblastic areas. In addition, there were rhabdoid cells present, which showed paranuclear cytoplasmic immunoreactivity for epithelial membrane antigen. The patient developed metastatic disease 6 months after surgical excision.- - - - - - - - - - ranking = 1keywords = membrane (Clic here for more details about this article) |
3/20. Osteogenic sarcoma of the prostate.A 76-year-old man was treated with bilateral orchiectomy, estramustine phosphate and pelvic irradiation for prostate cancer. Osteogenic sarcoma of the prostate developed 18 months after the treatment. Postmortem examination revealed that the tumor was 8 cm in diameter and had infiltrated into the bladder and rectal walls and had resulted in peritoneal dissemination. There was no distant metastasis. Macroscopically, the tumor was ashen, firm and relatively homogenous and diffusely spread. Histologically, it was composed of spindle and pleomorphic cells, which were making osteoid with calcification. There was no ordinary tubular formation as shown in adenocarcinoma of the prostate. No positive immunostaining for prostate-specific antigen, epithelial membrane antigen and cytokeratin (AE-1, AE-3) were confirmed. Positive immunostaining for nonepithelial marker vimentin was confirmed. The ultimate diagnosis was osteogenic sarcoma of the prostate.- - - - - - - - - - ranking = 1keywords = membrane (Clic here for more details about this article) |
4/20. Periosteal osteosarcoma of the mandible.We report a rare case of periosteal osteosarcoma of the mandible in a 15-year-old girl. Extension of the tumour into the bone marrow by way of the periodontal ligament is demonstrated.- - - - - - - - - - ranking = 34.524748273601keywords = ligament (Clic here for more details about this article) |
5/20. Chromophobe renal cell carcinoma with osteosarcoma-like differentiation.Sarcomatoid differentiation in renal cell carcinoma is thought to be the result of the dedifferentiation of the parent tumor, and it can be found in the chromophobe renal cell carcinoma just as other subtypes. We report a case of chromophobe renal cell carcinoma, which showed osteosarcoma-like differentiation. This is the first known case ever to be clearly identified as such. The patient was a 74-year-old man, and the CT scan revealed a huge retroperitoneal mass, which protruded from the lower half of the kidney and directly invaded the colon. Intraabdominal dissemination and metastases to the liver and lungs were also found. The resected tumor histologically showed sarcoma-like spindle cell proliferation and partly produced massive osteoid, which simulated the osteosarcoma. In addition, a typical histology of chromophobe renal cell carcinoma was found in part of the tumor. Immunohistochemically, spindle cells were reactive for epithelial membrane antigen, cytokeratin, and vimentin. The cell nests that were labeled by epithelial membrane antigen and cytokeratin were also found in the osteosarcoma-like area. We think that these phenomena were the result of "dedifferentiation" and metaplasia of the chromophobe renal cell carcinoma.- - - - - - - - - - ranking = 2keywords = membrane (Clic here for more details about this article) |
6/20. Reconstruction with autologous pasteurized whole knee joint II: application for osteosarcoma of the proximal tibia.Reconstruction of the knee joint for osteosarcoma of the proximal tibia is a formidable challenge. Here we present two patients whose knees were reconstructed with autologous grafts of whole-knee joint treated by extracorporeal pasteurization. Incorporation at the junction between host and pasteurized bone was evident. On the other hand, direct reattachment of the patellar tendon to the pasteurized tibia was not successful in case 1. In case 2, in contrast, the patella was divided followed by successful reconstruction at the osseous site. Avoiding reattachment of pasteurized ligamentous structure is recommended. The operation protocol is not ideal but so far may be superior to other reconstruction procedures because there are many fundamental complications such as low long-term survival of a massive prosthesis and the lethal risk of transfection (e.g. human immunodeficiency virus); moreover, immunological responses of the allograft can be avoided.- - - - - - - - - - ranking = 34.524748273601keywords = ligament (Clic here for more details about this article) |
7/20. Synovial sarcoma after chemotherapy for osteosarcoma: a case report.A 23-year-old man had eight cycles of adjuvant chemotherapy including doxorubicin, cisplatin, methotrexate, and ifosfamide and radical surgery for biopsy-proved osteosarcoma of the right fibular shaft. Two years after the initial diagnosis, he noticed a mass in the medial aspect of his right knee. magnetic resonance imaging scans revealed a soft tissue tumor measuring 2 x 2 cm in the pericapsular region of the right knee. Histologically, this soft tissue tumor was composed of spindle cells with occasional atypical mitoses and without matrix formation. Immunohistochemically, the tumor cells were positive for vimentin, cytokeratin, and epithelial membrane antigen, and negative for alpha smooth muscle actin. A fusion gene, SYT-SSX was detected with reverse transcription-polymerase chain reaction. From the results, the secondary tumor was diagnosed as a synovial sarcoma. The current case of double sarcomas is rare. Both sarcomas were diagnosed accurately using immunohistochemical and molecular procedures. This case suggests a positive association between a second tumor and chemotherapy including intraarterial perfusion of doxorubicin.- - - - - - - - - - ranking = 1keywords = membrane (Clic here for more details about this article) |
8/20. Second primary osteosarcoma with rosette-like structure in a patient with retinoblastoma.A Japanese male patient developed bilateral retinoblastomas at the age of 1 year, but remained continuously disease-free after enucleation of the left eye and radiation therapy to the right eye. He noticed a painless hard mass around the right temporal bone when he was 25 years old. biopsy specimen showed a small multi-nodular proliferation of tumor cells with prominent rosette-like structures. Eosinophilic material with focal mineralization was seen in the center of the rosettes. Immunostaining of the tumor cells showed positive reactions for epithelial membrane antigens CD 56 and CD 99. The patient was treated with systemic chemotherapy, and the tumor partially diminished. It is well known that a few osteosarcomas show a rosette-like appearance with production of osteoid in the center, but this is the first case of second primary osteosarcoma with prominent rosette-like features.- - - - - - - - - - ranking = 1keywords = membrane (Clic here for more details about this article) |
9/20. The clinical and diagnostic imaging findings of osteosarcoma of the jaw.OBJECTIVE: To clarify the valuable clinical features and diagnostic imaging findings regarding the diagnosis of osteosarcoma of the jaw (OSJ). MATERIALS AND methods: The initial symptoms and diagnostic imaging findings of 10 patients with OSJ were analysed. The points analysed on the diagnostic images were as follows: any widening of the periodontal ligament space of the teeth on the periphery of the OSJ; the presence of radial spicules and Codman's triangle; any signs of bone destruction; and the patterns of osteogenesis. RESULTS: All patients had pain and/or swelling of the affected site, and all OSJs, except for one edentulous case, showed a widening of the periodontal ligament space of the teeth on the periphery of the OSJ. Radial spicules or Codman's triangle were observed in only three cases (30%). Four out of five mandibular OSJs were osteolytic or osteolytic dominant with bone destruction, while, in contrast, four out of five maxillary OSJs were osteogenic or osteogenic dominant, and three out of the four maxillary OSJs did not show bone destruction. The osteogenic OSJ without bone destruction was similar to some benign cemento-osseous lesions of the jaw and thus was difficult to diagnose as OSJ based on the diagnostic imaging findings alone. CONCLUSION: Even though some OSJ showed features similar to the benign tumours of the jaw bone based on the diagnostic imaging findings, the pain and swelling of the affected site, and the widening of the periodontal ligament space of the teeth on the periphery of OSJ were considered to be common findings, which may help in making an accurate diagnosis of OSJ in this limited series.- - - - - - - - - - ranking = 103.5742448208keywords = ligament (Clic here for more details about this article) |
10/20. "Dedifferentiated" chordoma. A clinicopathologic and immunohistochemical study of three cases.Three cases of "dedifferentiated" chordoma arising in the sacrococcygeal region are presented. In all three cases, the "dedifferentiated" component arose de novo in conjunction with conventional chordoma. Two of these patients, whose tumors had a prominent malignant fibrous histiocytoma (MFH) component, died within 6 months of diagnosis. Both patients had lung metastases, one of which was histologically documented to be MFH. The third patient, whose initial tumor contained osteosarcoma, died 76 months after diagnosis and multiple recurrences. Most notable in this case was the absence of the "dedifferentiated" component (in this instance, osteosarcoma) in all of the local recurrences as well as the lung metastases. These were composed exclusively of conventional chordoma. None of the patients had a previous history of radiation therapy. The immunohistochemical staining pattern of conventional chordoma was similar to that of previous reports, where the epithelial-like cells stained for cytokeratin and epithelial membrane antigen. In addition, they stained for alpha-1-anti-chymotrypsin and vimentin. These latter two markers were also identified in the "dedifferentiated" component. As with "dedifferentiated" chondrosarcomas and liposarcomas, "dedifferentiation" in a chordoma usually portends an accelerated clinical course.- - - - - - - - - - ranking = 1keywords = membrane (Clic here for more details about this article) |
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