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H C Bauer

Publications and source records attributed to H C Bauer.

At least 37 records · Page 2Linked to original sources
PubMed1999

Clinical significance of genetic imbalances revealed by comparative genomic hybridization in chondrosarcomas.

DNA copy number changes were studied by comparative genomic hybridization (CGH) in 50 chondrosarcoma samples from 45 patients. Mean number of genetic aberrations in primary tumors was 4.8 +/- 1.8. The most frequently gained regions were 20q12-qter (37%), 20q (32%), 8q24.1-qter (27%), 20p (24%), and 14q24-qter (24%). Losses were 5.5 times less frequent than gains and observed mainly at Xcen-q21, 6cen-q22, and 18cen-q11.2 (11% each). Recurrent and metastatic tumors showed a mean of 4.0 +/- 2.2 aberrations per sample. The most frequently gained regions were chromosome 7 (4 cases), 5q14-q32 (4 cases), 6p (3 cases), and 12q (3 cases). Losses of DNA sequences were 3.4 times less frequent than gains. Histological tumor grade was significantly associated with metastasis-free survival (P = .002) and overall survival (P = .003), being the strongest prognostic factor tested. A statistically significant correlation was found between gain at 8q24.1-qter and shorter overall survival (P = .01) but not with local recurrence or metastasis-free survival. Gain at 14q24-qter was associated with a trend to shorter overall survival (P = .05) but neither with an increased risk for local recurrence nor with metastasis-free survival. In a multivariate analysis, only the tumor grade associated with overall survival (P = .02). In a multivariate analysis together with the tumor grade, gain at 8q24.1-qter did not retain its significance (P = .44), indicating that this imbalance is not an independent prognostic factor.

Adult↗
PubMed1999

Ki-67 is strongly prognostic in synovial sarcoma: analysis based on 86 patients from the Scandinavian Sarcoma group register.

In a study based on formalin-fixed paraffin-embedded material from 86 patients with primary synovial sarcoma located in the extremities or on the trunk wall, the prognostic importance of MIB-1 index, p53-expession and tumour size was analysed. Multivariate analysis identified two metastatic risk factors: increasing tumour size and MIB-1 > 9%. The 5-year metastasis-free survival-rate for patients with tumour size < or = 5 cm + MIB-1 < 10% was 0.83 (95% confidence interval (CI) 0.64-0.92) compared to 0.31 (95% CI 0.11-0.53) in cases with tumour size > 5 cm + MIB-1 > or = 10%. Our study shows that metastatic disease in synovial sarcoma is closely related to MIB-1 index. Using our model based on tumour size and MIB-1 index, cases with good and poor prognosis can easily be discriminated. Therefore our model can be used to identify patients who should be considered for adjuvant chemotherapy.

Antigens, Nuclear↗
PubMed1999

MR imaging of lipoma and liposarcoma.

PURPOSE: To evaluate whether lipoma, atypical lipomatous tumors, and liposarcomas can be differentiated by MR images. MATERIAL AND METHODS: The MR images of 59 lipomatous lesions and liposarcomas were retrospectively reviewed. Apart from size, surgical site, location and margins, the percentage of fat of the tumor volume was assessed as none, 1-75%, 75-95%, or 95-100%. RESULTS: None of the 18 liposarcomas contained fat that could be recognized by MR imaging. The 3 atypical lipomatous tumors all contained fat but less than 75% of the tumor volume. In 32 of 38 ordinary lipomas, the percentage of fat was 95-100%, and in 4 less than 95% of the tumor volume. Two lipomas did not contain fat that could be recognized by MR imaging. CONCLUSION: A lesion which predominantly has a fat signal is, in all probability, an ordinary lipoma. Lesions with less fat, but still mostly fatty, may either be lipoma or atypical lipomatous tumor. In this group, the discrimination between these two entities cannot be based upon imaging features. In the absence of a fat signal, liposarcoma or lipoma cannot be differentiated from other soft tissue tumors.

Adipose Tissue↗
PubMed1999

110 subfascial lipomatous tumors. MR and CT findings versus histopathological diagnosis and cytogenetic analysis.

PURPOSE: To evaluate whether liposarcoma, atypical lipomatous tumors and lipoma can be differentiated radiologically. MATERIAL AND METHODS: We have retrospectively analyzed CT and/or MR images of 110 subfascial lipomatous lesions. The amount of fat within the tumors was visually graded from the images as: none, 1-75%, 75-95% or 95-100%. The structure of non-fatty tumor components was compared. The images were compared to histopathology and in 37 cases to cytogenetic findings. RESULTS: Only 4 of 20 liposarcomas contained fat. All 4 lesions, histopathologically diagnosed as atypical lipomatous tumors, contained fat but less than 75% of tumor volume. All lesions with more fat than 75% of tumor volume were histologically diagnosed as lipomas. However, one-third of the karyotyped lipomas had ring chromosomes which are considered typical for atypical lipomatous tumors. CONCLUSION: When a tumor is composed more or less solely of fat, the diagnosis of a lipoma or atypical lipomatous tumor with a phenotype simulating a lipoma can be assumed. When the fat content is less than 75% of the tumor volume or non-fatty nodules are found, biopsies from different tumor components have to be performed to exclude malignancy. When no fat is found, imaging does not help in differentiating lipoma or liposarcoma from other soft tissue tumors.

Adolescent↗
PubMed1999

Malignant fibrous histiocytoma of bone: a retrospective EMSOS study of 125 cases. European Musculo-Skeletal Oncology Society.

In an effort to learn more about malignant fibrous histiocytoma (MFH) of bone and its prognosis with different treatment approaches, the European Musculo-Skeletal Oncology Society (EMSOS) initiated a retrospective survey among its members. Data requested included patient and treatment variables and outcome. The information on all patients with histologically proven, primary, localized osseous extremity MFH was analyzed if surgical tumor removal was performed and disease status was documented for at least one follow-up date. 125 such patients were evaluable (74 male, 51 female; median age 34 years; tumor site femur 81, tibia 26, humerus 12, other 6). Local treatment was surgery only (110) or surgery plus radiotherapy (15). Chemotherapy was used in 97/125. On last follow-up, 85 patients remained in remission, 33 had developed metastases, 6 a local recurrence, and 1 a combined relapse. With a median follow-up of 3.9 years for patients at risk, actuarial 5-year disease-free survival was 59%. In univariate analyses, younger age and the use of chemotherapy were associated with a more favorable outcome, as was limb-salvage surgery. 23 of 66 tumors with information on response to preoperative chemotherapy responded well (> 90% necrosis). Among these 23, only one relapsed.

Adolescent↗
PubMed1999

Clinical course in synovial sarcoma: a Scandinavian sarcoma group study of 104 patients.

We analyzed treatment and outcome in 104 Scandinavian patients with synovial sarcoma in the extremities or trunk wall, diagnosed between 1986 and 1994. Only surgically treated patients without metastases at diagnosis were included. Median follow-up of survivors was 6 (3-11) years. 34 patients developed metastases. The overall 5- and 7-year survival rates were 0.76 (95% CI 0.66-0.83) and 0.69 (0.58-0.78), respectively. Large tumor size and amputation were significantly associated with impaired metastasis-free survival. Patients with local recurrence had a higher risk of metastases following the local event. Local excision with inadequate margin was associated with a higher risk of local recurrence.

Adolescent↗
PubMed1999

Failures after operation for skeletal metastatic lesions of long bones.

This study was based on 192 patients treated surgically for 228 metastatic lesions of the long bones from 1986 through 1995. The survival rate was 0.3 at 1 year after surgery. The surgical treatment consisted of resection and reconstruction of the involved bone (18), intralesional curettage (133), or stabilization only (77). Reconstruction was achieved by an endoprosthesis in 54 cases, by an osteosynthetic device in 162, by cement only in 10. In two cases no reconstruction was performed. The local failure rate was 11% and the median time to failure was 8 months. Local failure was most frequent in patients with kidney cancer (24%) and in diaphyseal and distal femoral lesions (20%). Among 162 operations involving osteosynthetic devices, 22 (14%) were failures as compared with one of 54 (2%) endoprostheses. Sixty percent of the patients received preoperative or postoperative radiotherapy. Five of the six patients who had surgery for local tumor progression had not received radiotherapy. Eight of 10 nonunions and all five patients who developed a stress fracture had been treated with radiotherapy. It is concluded that endoprosthetic reconstructions are preferable to osteosynthetic devices. The skeletal complications associated with radiotherapy may be circumvented by the use of endoprostheses.

Adult↗
PubMed1998

Fine needle aspiration (FNA) cytology in the diagnosis of recurrent soft tissue sarcoma.

We have used FNA cytology to diagnose suspected local recurrences of soft tissue sarcoma. Since 1991, a total of 95 FNA cytologies were performed on 86 patients. There were 47 local recurrences, of which 44 were diagnosed correctly by FNA cytology; one biopsy was inconclusive, and two lesions were incorrectly assessed as benign. Thirty-nine patients proved to have benign lesions in the scar area examined cytologically on 50 occasions. None of the specimens was regarded as malignant, but in four cases FNA cytology was inconclusive. Overall, there were 5% inconclusive cytological biopsies, 0% falsely malignant and 5% falsely benign. The inconclusive and false-negative cytological diagnoses had no important clinical consequences. FNA biopsy provides a simple means of diagnosing local recurrence of soft tissue sarcoma.

Adolescent↗
PubMed1997

Cytotoxic and genotoxic effects of 4-hydroxynonenal in cerebral endothelial cells.

Oxygen free radicals are produced in the central nervous system (CNS) as a consequence of normal physiological metabolic reactions of neuronal cells, but there is evidence accumulating that they are also implicated in the processes leading to a number of pathological changes in the brain. A general mechanism whereby oxygen free radicals induce tissue damage is lipid peroxidation (LPO), which generates a large variety of water-soluble carbonyl compounds. Due to their high reactivity, we focused our investigations on 4-hydroxyalkenals, in particular on 4-hydroxynonenal (HNE), the major 4-hydroxyalkenal. Two phenotypes of cerebral endothelial cells (cECs) were treated with various concentrations of 4-hydroxynonenal and the cyto- and genotoxic effects studied. The cytogenetic endpoints determined were chromosomal aberrations and the induction of micronuclei. Three hours of incubation with HNE induced significantly elevated levels of chromosomal aberrations at concentrations > or = 1 microM and micronuclei at concentrations > or = 10 microM in both cEC phenotypes, compared to the controls. Cytotoxicity was observed at a concentration of 50 microM HNE and was significantly higher in the elongated and spindle-shaped cEC phenotype (type II) than in the epithelial cEC phenotype (type I). The results indicate that cECs are affected by HNE even at low concentrations with minor differences between the two cEC phenotypes.

Aldehydes↗
PubMed1997

Use of 99mTc-MIBI scintigraphy in the evaluation of the response of osteosarcoma to chemotherapy.

The use of gamma camera scintigraphy with technetium-99m hexakis-2-methoxyisobutylisonitrile (99mTc-MIBI) for assessment of the response of high-grade osteosarcoma to preoperative chemotherapy was evaluated. Twelve patients with osteosarcoma of the extremities underwent planar examination with 99mTc-MIBI before and after preoperative chemotherapy according to the recommendations of the Scandinavian Sarcoma Group. After calculating a quotient for the tumour and the average activity of both extremities and correcting for background activity, the change in uptake between the two examinations was assessed. This was compared with histological examination of the ultimately resected specimen in 11 patients and progressive clinical disease in one. All the 11 tumours undergoing histological examination showed cellular necrosis of between 50% and 100% as well as a reduced uptake of 99mTc-MIBI, while the single progressive tumour showed an increased uptake. There was a correlation between the reduction of radiopharmaceutical uptake and the histological response in the entire series, while the variation was too large to allow conclusions in individual patients. This variation may have biological reasons or may be due to the planar imaging technique, which only allows semiquantitative evaluation. The technique reflects response to therapy but is not yet clinically applicable for the identification of poor responders, which would serve as a basis for alteration of the chemotherapy regimen. In order to evaluate whether such a role could be fulfilled, further studies using single-photon emission tomography with correction for attenuation and scattering of photons are necessary.

Adolescent↗
PubMed1997

Posterior decompression and stabilization for spinal metastases. Analysis of sixty-seven consecutive patients.

The neurological function, survival, and rehabilitation of sixty-seven consecutive patients who had been managed operatively for spinal metastases with epidural compression were assessed. The epidural compression was in the thoracic spine in forty-one patients and in the lumbar spine in twenty-six. According to the system of Frankel et al. for the assessment of neurological function, twenty-six patients had a major neurological deficit (grade B or C), thirty-two had a minor deficit (grade D), and nine had no deficit (grade E). None of the patients had an operation to treat a pathological vertebral fracture without epidural compression. The operative treatment included wide decompression through a posterior approach followed by stabilization without bone-grafting. A Cotrel-Dubousset device was used in thirty-two patients; an Olerud posterior fixator, in sixteen; an Isola device, in twelve; and another device, in seven. The most common complication was wound infection (eleven patients). There were no perioperative or immediate postoperative deaths (within fourteen days). The rate of survival was 51 per cent (thirty-four of sixty-seven) at six months and 22 per cent (fifteen of sixty-seven) at twelve months. Over-all, forty-four of the fifty-eight patients who had had a neurological deficit preoperatively had complete or partial neurological recovery within the first two weeks postoperatively. The nine patients who had not had a neurological deficit preoperatively retained normal neurological function postoperatively. Thirty-eight of the forty-four patients who were alive at three months and twenty-nine of the thirty-four who were alive at six months were still able to walk. Thirty-nine of the forty-nine patients who survived more than two months were able to return home for a median of seven months. Fourteen patients had a reoperation on the spine. Six of these patients had recurrent epidural compression at another level of the spine, and five had recurrent compression at the previously treated level. Three patients had a reoperation because of loosening of the implant. The results of this study suggest that neurological function can be maintained or improved by decompression and stabilization through a posterior approach as treatment for spinal metastases.

Adult↗
PubMed1997

Expression of a chemotactic cytokine (MCP-1) in cerebral capillary endothelial cells in vitro.

A full-length cDNA encoding the porcine monocyte chemoattractant protein-1 (pMCPC-1) was isolated from growth-stimulated porcine cerebral capillary endothelial cells (cEC); the pMCP-1 cDNA showed 89% identity to human MCP-1 and was isolated by use of subtractive hybridization and differential screening of two phenotypically different sub-populations of cloned cEC. pMCP-1 was abundantly expressed in cEC grown in the presence of FCS, ECGF and heparin whereas lower expression was observed in cEC kept in FCS-supplemented medium only. As shown by Northern blot analysis, no pMCP-1 transcripts were present in total RNA derived from freshly isolated brain capillaries, large brain vessels or whole brain homogenate. MCP/JE expression was also demonstrated in ECGF/heparin-treated murine cEC. Astrocytes and smooth muscle cells grown in FCS-supplemented medium did not show MCP-1 expression. Treatment of porcine cEC with TNF-alpha increased pMCP-1 mRNA levels in a dose-dependent manner. These data further support the notion that cerebral capillary endothelial cells actively participate in processes of CNS host defense.

Amino Acid Sequence↗
PubMed1997

Comparison of technetium-99m-MIBI and technetium-99m-tetrofosmin uptake by musculoskeletal sarcomas.

UNLABELLED: Technetium-99m-MIBI was initially developed for heart studies but it can also be used to depict tumors, predict multidrug resistance and evaluate chemotherapy. Recently, 99mTc-tetrofosmin, which exhibits similar physical properties, has been launched for heart studies. Tumor uptake and prediction of multidrug resistance have also been reported regarding the latter tracer. A comparison of these two tracers regarding the detectability of musculoskeletal sarcoma has been made. METHODS: Twenty patients with musculoskeletal sarcoma of the extremities or pelvis underwent planar examination after the administration of 99mTc-MIBI and 99mTc-tetrofosmin with an interval of 2-7 days. The tumor activity was compared with one ipsilateral and one contralateral background region. RESULTS: There was a small, but not significant, difference in favor of 99mTc-MIBI with regard to both background regions. CONCLUSION: Technetium-99m-MIBI and 99mTc-tetrofosmin can both be used to visualize musculoskeletal sarcomas. The choice may depend on which agent is used routinely for myocardial studies in the laboratory.

Adolescent↗
PubMed1996

Reconstruction in metastatic destruction of the acetabulum. Support rings and arthroplasty in 12 patients.

In 12 patients with acetabular metastases, we reconstructed the hip with a support ring, cement, and Charnley prosthesis with a 22 mm head. There were no immediate postoperative deaths or cardiovascular complications. Dislocations occurred in 5 patients, 1 of whom required open reduction. At follow-up, 3 patients were alive 11, 15, and 18 months after surgery. 9 patients died after 8 (2-13) months. All patients obtained relief from pain, became ambulatory and were discharged to their homes. 1 patient had rapid disease progression with pathologic fracture and cranial dislocation of the support ring. Among the remaining 11 patients, the hip has not again caused pain or limited function. There were no signs of loosening, except in the patient with fracture of the hemipelvis. Remineralization was observed in 2 breast cancer patients after chemotherapy. Hip reconstruction can restore painless function until death in cancer patients with severe destruction of the acetabulum.

Acetabulum↗