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S Blasius

Publications and source records attributed to S Blasius.

69 records · Page 4Linked to original sources
PubMed1992

Chondroblastoma of bone. A clinical, radiological, light and immunohistochemical study.

The clinical and morphological findings of 53 chondroblastomas in the files of the Bone Tumour Registry of Westphalia are presented. The mean age of all patients was 19.2 years. The male-to-female ratio was 1.5:1. Forty-two of the tumours (79.8%) were located in the long tubular bones and short tubular bones of the hands and were closely related to the growth plate. Six cases (11.3%) were found in the flat bones, 4 cases (7.5%) in the tarsal bones and 1 case (1.9%) in the craniofacial bones. The characteristic radiological feature of 44 investigated lesions was a mostly eccentric radiolucency with a geographic pattern of bone destruction and matrix calcifications. Periosteal reaction was evident in 9% of the cases. Most tumours demonstrate the typical morphological features of chondroblastoma, but 3 cases resembled a giant cell tumour. In 2 cases a haemangiopericytoma-like growth pattern was observed. Nine of the tumours had an aneurysmal bone cyst-like component. Vascular invasion was seen in 1 case. Immunohistochemically most cells in 30 of the cases and fetal chondroblasts in 3 cases were strongly positive with vimentin and S-100 protein. Collagen type II was positive in the chondroid matrix of the tumours and in fetal cartilage tissue; collagen type VI was present focally around individual tumour cells and was always seen in the chondroid matrix of the lesions and in fetal cartilage. These findings support the cartilaginous nature of these tumours. In paraffin sections, 46.6% of the cases revealed a distinct positive reaction of some tumour cells with the monoclonal cytokeratin antibody KL1 (molecular weight 55-57 kDa). Only 4 of them demonstrated a coexpression with the other monoclonal cytokeratin antibody CK (clone MNF 116, molecular weight 45-56.5 kDa). In paraffin sections all fetal chondroblasts were negative with both cytokeratin antibodies. Frozen sections of 3 tumours showed a strong positive reaction with both cytokeratin antibodies in many chondroblasts, indicating an "aberrant" cytokeratin expression. Osteoclast-like giant cells stained positive with leucocyte-common antigen (LCA) and with the macrophage-associated antibody KP1, but were negative with the other macrophage-associated antibody MAC 387. Recurrence rate was 10.7%. The clinical course of all tumours was benign.

Adolescent↗
PubMed1992

"Solid" variant of aneurysmal bone cyst.

A case of the so-called "solid" variant of aneurysmal bone cyst is reported. A 12-year-old girl with a few weeks' history of backache presented with a tender palpable mass located thoraco-spinal in the back at Th 3. Radiologically, the lesion was consistent with conventional aneurysmal bone cyst. Morphologically, it showed fibroblastic, fibrohistiocytic, fibromyxoid, osteoclastic and osteoblastic components as well as small aneurysmal sinusoids. Based on four other well documented cases, the clinico-pathological features and the differential diagnostical problems are discussed.

Bone Cysts↗
PubMed1992

Nd:YAG laser-photocoagulation: acute electrophysiological, hemodynamic, and morphological effects in large irradiated areas.

Laser-photocoagulation (LPC) of arrhythmogenic myocardium has been reported to successfully ablate ventricular tachycardia. The purpose of this study was to investigate the acute hemodynamic and electrophysiological effect of continuous laser energy (Nd:YAG, 1060 nm) applied via a 0.4-mm quartz fiberoptic on the epicardial surface of the heart in nine dogs. A total of 51 +/- 2.3 pulses was delivered in each animal to induce homogeneous tissue necrosis. Applied energy was 12.3 +/- 2.7 J/mm2, irradiated surface measured 12.6 +/- 3.0 cm2, lesion depth was 6.3 +/- 1.2 mm (range: 5.0-8.1 mm), lesion volume was 8.1 +/- 2.8 cm3 (6.8% of left ventricular [LV] mass). After LPC, epicardial stimulation threshold significantly rose from 1.0 +/- 0.3 to 10.2 +/- 4.9 mA in the border zone to nontreated tissue and from 0.9 +/- 0.4 to 32 +/- 15.7 mA in the center of the lesions. Loss of epicardial activation in the irradiated areas could be demonstrated by epicardial mapping. Ventricular extrasystoles during LPC were seen in all dogs, ventricular tachycardia in seven, and ventricular fibrillation in two dogs. After LPC, cardiac output and LV dP/dtmax significantly decreased by 14.2% and 11.2%. LPC induced predictable homogeneous tissue edema, eosinophilic staining, contraction band necrosis, and sharp demarcated hemorrhagic border zones with a sharp electrical border zone to nontreated tissue and loss of epicardial activation. During LPC, various arrhythmogenic effects could be observed. However, no persistent arrhythmic activity developed after LPC. The results confirm the feasibility of epicardial LPC of the myocardium. Although not rested in this study, LPC of arrhythmogenic tissue may also be feasible as a treatment modality of ventricular tachycardia.

Animals↗
PubMed1992

[Non-Hodgkin's lymphoma with primary osseous manifestation, from the files of the Bone Tumor Registry of Westphalia].

30 cases of non-Hodgkin-lymphoma with primary bone manifestation were selected from the files of the Bone Tumor Registry of Westfalia from 1975 until 1992. Clinical data and radiologic aspects were evaluated. 60% of the lesions were localized within the long bones (femur 10, humerus 6, tibia 2). The lymphomas were classified based on paraffin-embedded material in combination with immunohistochemical findings according to the updated Kiel-classification. 29 B-cell lymphomas and one T-cell lymphoma of medium-sized pleomorphic type were found. 5 B-cell lymphomas were of low and 23 of high malignancy. Almost 50% of the tumors were of centroblastic type. The Kiel-classification was not applicable for one lymphoma, 3 others could not be subclassified because of shrinking artefacts. Prognosis in patients with localized disease (9 cases) was favorable, whereas only 25% of patients with generalized disease (12/cases) survived for 3 years or longer.

Bone Neoplasms↗
PubMed1991

Apolipoproteins and immunohistological differentiation of cells in the arterial wall of kidneys in transplant arteriopathy. Morphological parallels with atherosclerosis.

22 nephrectomy specimens of renal allografts in chronic rejection after periods between 3 and 96 months, were studied immunohistologically. Various cell types in the arterial wall were characterized with antibodies specific against different cells of the mononuclear phagocyte system, against smooth muscle cells, and against differentiating lymphoid cells. In addition, the metabolism of lipoproteins was investigated using appropriate antibodies against several apolipoproteins. Subendothelial plaques of foam cells were found to consist of macrophages in foamy transformation. At the stage of intimal fibrosis the smooth muscle cells are more prominent. Lymphatic infiltration consists almost exclusively of T-lymphocytes. Apolipoprotein analysis reveals deposits of Apo A1, A2 and B1, most of them extracellular. According to these results, it is not only immunologic factors that are involved in arterial wall reactions during chronic transplant arteriopathy, but disorders of the lipoprotein metabolism--probably due to endothelial dysfunction--are also playing an important role like in atherosclerosis.

Adolescent↗
PubMedDate not supplied

[The use of massive allograft in reconstruction following resection of bone tumors of the extremities].

Reported are indications, techniques and clinical outcome of 45 patients with resection of a primary malignant or aggressive benign tumor of the extremities, reconstructed with an allograft. The goal of this procedure is to achieve a wide resection of the tumor and to reconstruct the defect saving the limb. Bridging the osseous defect, we used an osteochondral allograft (14), intercalary allograft (16), allograft arthrodesis (14) and composite reconstruction (1). There were 3 deep infections, 3 superficial infections, 2 pseudarthrosis and 1 rejection found as complications. After local revision of the infections by allograft explantation and temporary implantation of antibiotic-loaded chains, another allograft could be implanted with success. Using different, individual adapted operative methods and allografts, a broad spectrum of bone defects after resection of bone tumors and, if necessary revisions, can be treated.

Adolescent↗
PubMedDate not supplied

[Value of sonographically guided biopsy in the histological diagnosis of benign and malignant soft-tissue and bone tumors].

In 41 patients, an ultrasound guided needle biopsy for histological diagnosis of benign and malignant soft tissue and bone tumors was carried out. In 32 cases following ultrasound guided needle biopsy of the soft tissue component of tumor a final diagnosis could be histopathologically determined; in 5 additional cases, due to the small amount of biopsy, a tumor grouping was able to be ascertained, a further tumor differentiation however could not be made. In 4 cases with cystoid tumors it was not possible to make a diagnosis. The deciding advantage of the new method of ultrasound guided needle biopsy presented here, in comparison to the so called blind tumor biopsy, is that by way of a picture control on the ultrasound screen exact positioning of the biopsy needle is possible. The ultrasound monitor enables one to observe the biopsy procedure, various biopsies from different sites of the soft tissue components of the tumor are possible through one biopsy canal. The new method of the ultrasound guided needle biopsy of benign and malignant soft tissue and bone tumors should however only be carried out in tumor centers.

Adolescent↗
PubMedDate not supplied

Assessment of molecular genetic detection of chromosome translocations in the differential diagnosis of pediatric sarcomas.

BACKGROUND: Recent studies have shown that many types of soft-tissue sarcomas are characterized by specific chromosomal translocations, which are likely to be of etiologic significance. In order to evaluate their diagnostic impact, a panel of 129 sarcomas comprising 78 Ewing's tumors (ET), 19 rhabdomyosarcomas (RMS), 20 neuroblastomas (NB), 9 synovialsarcomas, 2 esthesioneuroblastomas, and 1 desmoplastic small-round-cell tumor (DSRCT) were analysed for the occurrence of the major recurrent translocations, such as t(11;22)(q24;q12), t(21;22)(q22;q12), t(11;22)(p13;q12), t(2;13)(q35;q14), t(1;13)(p36;q14), and t(X;18)(p11;q11). METHODS: Nitrogen-frozen tissue material was analysed by means of Reverse Transcription followed by PCR (Polymerase-Chain Reaction) and nested PCR (RT-PCR). Specificity of the PCR products obtained was confirmed by non-isotopic Southern-Blot analysis with gene-specific probes and/or automated direct sequence analysis. RESULTS: 75 ETs have been shown to carry either a t(11;22) or t(21;22) translocation by identification of chimeric EWS-FLI-1 or EWS-ERG gene-fusion transcripts respectively. 3 ETs were lacking EWS/FLI-1 or EWS-ERG fusion products. 2 of these tumors were shown on review to have unusual morphological features for ETs. 8/19 RMS were initially diagnosed as alveolar RMS. These tumours were shown to carry either a t(2;13) translocation exhibiting chimeric PAX3-FKHR fusion transcripts or a t(1;13) translocation with PAX7-FKHR chimeric gene products. One RMS of the embryonal group also carried a t(1;13) translocation. Reevaluation demonstrated a partly alveolar morphology. In 8/9 synovial sarcomas a t(X;18) translocation was identified. Expression of a EWS-WTI gene-fusion product associated with a t(11;22) translocation was found in the DSRCT. None of these rearrangements were detected in the NBs and 2 esthesioneuroblastomas. CONCLUSIONS: Our results support the concept that the major recurrent translocations are histogenetically specific for a subset of sarcomas. Thus, the detection of tumor type-specific translocations represents an extremely useful diagnostic modality as an adjunct to surgical pathology.

Base Sequence↗
PubMedDate not supplied

[Osteosarcoma in 2 siblings. A case report].

With a brother and sister, osteosarcoma developed at the age of 11 and 14 respectively. With both there was no previous retinoblastoma or other bone disease with a proclivity to develop osteosarcoma. We discuss possible explanations for familial aggregation of osteosarcoma, citing external or genetic factors. We suggest that it is the retinoblastoma gene RB and the tumor suppressor gene p53 which play an important part in the development of osteosarcoma.

Adolescent↗
PubMedDate not supplied

Periosteal chondroma: MR characteristics.

PURPOSE: The purpose of this study was to describe the MR characteristics of periosteal chondroma. METHOD: MR images of 12 proven cases of periosteal chondroma were analyzed with reference to tumor morphology and size. MR features were correlated with radiographic and pathologic findings. RESULTS: Tumor size ranged from 1 to 7 cm in maximum diameter with a mean value of 2.6 cm. On MR images, a soft tissue mass at the bone surface with pressure erosion of adjacent cortical bone could be identified in all cases. All lesions were bordered by a hypointense rim (100%) and frequently showed a lobulated configuration (75%). Edema of medullary bone or soft tissues was not observed in any of the cases. Signal intensity of cartilaginous tumor tissue was typically hypo-or isointense relative to muscle on T1-weighted (100%) and hyperintense relative to fat on T2-weighted (92%) and T2*-weighted (100%) MR images. Radiographically significant calcifications of the tumor matrix, present in half of the cases, caused focal signal loss on MR images of all pulse sequences. Contrast enhancement was observed predominantly at the periphery of the lesions (100%), which on pathologic examinations typically contained fibrovascular bundles, surrounding the cartilage lobules. CONCLUSION: Periosteal chondroma appears to have a relatively typical MR appearance, which reflects the histologic composition of the lesion. In addition to radiography, MRI therefore can substantially aid in the preoperative diagnosis of this rare bone lesion.

Adolescent↗
PubMedDate not supplied

Chondroid tumors arising from the meninges--report of 2 cases and review of the literature.

Chondroid tumors are rare intracranial tumors usually arising from the base of the skull. We present 2 cases of intracranial cartilaginous tumors with unusual location. In case 1, a 19-year-old woman, a chondroma of the falx cerebri with extensive secondary ossification was diagnosed. In case 2, a 30-year-old woman, a low-grade chondrosarcoma was resected from the right frontal lobe. Both patients showed an uneventful clinical course without evidence of disease 4.5 and 6 years after total extirpation. Our cases show that chondromas and low-grade chondrosarcomas of the dura and meninges usually occur in young adults with a good prognosis after complete extirpation.

Adult↗