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Gunhild Mechtersheimer

Publications and source records attributed to Gunhild Mechtersheimer.

At least 19 recordsLinked to original sources

Long-term remission of children with relapsed and secondary anaplastic large cell non-Hodgkin lymphoma (ALCL) following treatment with pulsed dexamethasone and low dose etoposide.

Anaplastic large cell lymphoma (ALCL) accounts for approximately 15% of childhood NHL. Relapsed ALCL represents a formidable challenge because outcome is poor despite the use of high-dose chemotherapy regimens. We report two patients with relapsed T-type and 0-type ALCL who achieved long-term 3rd and 4th remissions with 4-weekly oral dexamethasone (DEX) and etoposide pulses for 2 years. This regimen also induced and maintained remission in a third patient with Nijmegen breakage syndrome (NBS) with secondary T-type ALCL. These patients demonstrate that low-intensity oral chemotherapy can induce long-term remissions and offer a curative perspective in refractory, relapsed and secondary ALCL.

Antineoplastic Combined Chemotherapy Protocols↗

Treatment of neuroblastoma-related opsoclonus-myoclonus-ataxia syndrome with high-dose dexamethasone pulses.

Opsoclonus-myoclonus-ataxia-syndrome (OMS) represents a rare neuroblastoma-associated paraneoplastic syndrome that commonly results in neurologic deficits despite tumor resection and immunosuppressive therapy. We describe the response of five such children to high-dose dexamethasone pulses including two patients in whom previous glucocorticoids, rituximab, and cytostatic drugs were not successful. All patients had MYCN non-amplified tumors that were detected 1 to 7 months after the onset of the OMS or ataxia. This treatment resulted in a good partial response in three and in complete remission in two patients. Our results show that dexamethasone pulses are likely to be useful for both, first-line- and salvage-therapy for OMS-patients.

Adrenal Gland Neoplasms↗

Perioperative outcome in sarcoma surgery.

INTRODUCTION: Soft tissue sarcomas (STS) are rare tumors accounting for less than 1% of all malignancies. Although disease-specific surgical management is increasingly important, only few data are available for STS. Here, we analyze a single institution setting focusing on perioperative surgical and clinical parameters. METHODS: Prospectively gathered data of all adult patients undergoing surgery for STS including gastrointestinal stroma tumors (GIST) between October 2001 and October 2004. Patients undergoing only biopsy or ambulatory surgery were excluded. Statistical analysis was performed using SAS(R) software and patient's data from a computerized sarcoma registry. RESULTS: 159 patients with a median age of 60.2 years underwent a total of 179 operations. Three major sites of occurrence were notified: the visceral cavity (VIS) (36.3%), the retroperitoneum (RET) (31.3%), and the extremities (EXT) (27.4%). GIST (53.9%) were the most common type in the VIS, liposarcoma (62.5%) in the RET, and either liposarcoma (30.6%) or malignant fibrous histiocytoma (28.6%) in the EXT. Recurrence was treated in more than half of the patients with RET STS, and in almost one third of the EXT lesions, while primary occurrence dominated in the VIS. Median operation times in the VIS, RET, and EXT were 210, 240, and 120 min, respectively. Blood loss was 300, 500, and 50 ml for VIS, RET, and EXT operations. Morbidity was 26.2, 30.4, and 34.7% in VIS, RET, and EXT operations, respectively (reoperation rates were 9.4, 5.4, and 14.3%). Mortality was 1.5, 8.9, and 2.0% for VIS, RET, and EXT. Length of hospital stay in the groups was comparable. CONCLUSION: STS surgery of a single surgical unit contains predominantly VIS, RET, and EXT tumors. The STS subtype varies with location, as does length of operation, blood loss, morbidity, mortality, and reoperation rate. These data are helpful for planning the perioperative management of adult patients with STS and can be used for prognostic analyses.

Aged↗

COX-2 upregulation in thymomas and thymic carcinomas.

The treatment of advanced stage thymomas and thymic carcinomas is a multimodal therapy. New therapeutic targets are currently under investigation, including the epidermal growth factor receptor (EGFR) as well as KIT. A number of studies have shown protumorigenic potential of Cyclooxygenase-2 (COX-2) in a variety of human malignancies, but so far it is unknown whether COX-2 is expressed in primary malignancies of the thymus. Using tissue microarrays, the expression of COX-2, microsomal-PGES-1 and -PGES-2 (mPGES-1 and mPGES-2), as well as EGFR was evaluated in different subtypes of thymoma and thymic carcinomas. COX-2 was expressed in all subtypes as determined by immunohistochemistry. Some cases of type B2 and thymic carcinomas had COX-2 staining levels classified as mild to moderate. However, when measuring the optical color intensity, no significant differences could be detected. Concerning the expression levels, a weak correlation between the expression of COX-2, mPGES-1 and mPGES-2 as well as EGFR was found. Furthermore, additional cases of thymomas and thymic carcinomas were analyzed by COX-2 Western immunoblot analysis and were compared to normal thymi. The analysis showed that thymomas and thymic carcinomas had a significantly stronger COX-2 expression than that of the normal thymi (p < 0.04). In summary, COX-2 is expressed in all subtypes of thymomas and thymic carcinomas and thus represents, in addition to EGFR and KIT, a potential therapeutic target. Further studies are needed in order to determine whether a combined therapy using COX-2 inhibitors in addition to the evolving anti-EGFR antibody therapy may be considered as a treatment option.

Adult↗

Huge primitive neuroectodermal tumor of the pancreas: report of a case and review of the literature.

Primitive neuroectodermal tumor (PNET) of the pancreas is an extremely rare tumor that usually occurs in children or young adults. We report a case of a 33-year-old male patient with an 18 cm multiply 18 cm multiply 16 cm mass arising from the pancreatic body and tail with a one-day history of abdominal pain. Initial CT scan showed no signs of metastatic tumor spread. The tumor caused intrabdominal bleeding and the patient underwent primary tumor resection including partial gastrectomy, left pancreatic resection and splenectomy. Diagnosis of PNET was confirmed by histology, immunohistochemistry and FISH analysis. All neoplastic cells were stained positive for MIC2-protein (CD99). Approximately one month after surgery, several liver metastases were observed and the patient underwent chemotherapy according to the Euro-Ewing protocol. Subsequent relaparotomy excluded any residual hepatic or extrahepatic abdominal metastases. Although PNET in the pancreas is an extremely rare entity, it should be considered in the differential diagnosis of pancreatic masses, especially in young patients. This alarming case particularly illustrates that PNET in the pancreas although in an advanced stage can present with only a short history of mild symptoms.

12E7 Antigen↗

Mutational status of the epidermal growth factor receptor (EGFR) gene in thymomas and thymic carcinomas.

Epithelial tumours of the thymus (thymoma, thymic carcinoma) are rare tumours of the anterior mediastinum. Current treatment options of advanced stage thymomas and thymic carcinomas include a multimodal therapy with radio- and chemotherapy as well as surgery. In recent years, new therapeutic targets such as EGFR (epidermal growth factor receptor), COX-2 and KIT have emerged as new potential therapeutic targets. So far, EGFR mutational status of different subtypes of epithelial tumours of the thymus has been analyzed only inappropriately. We have investigated 20 different subtypes of thymomas (type A, AB, and B3) and thymic carcinomas for mutations in exons 18, 19, 20, and 21 of the EGFR gene and performed immunohistochemistry for EGFR. Concerning immunohistochemistry, most of the cases (17/20) had a strong positive staining. Although sequence alterations were found in four samples, none of these alterations led to amino acid changes in the tyrosine kinase domain of EGFR comparable to those in non-small cell lung cancer. Thus EGFR-expression in thymic tumours does not rely on mutations in critical functional (activation) domains of the EGFR-gene. Experimental and therapeutic approaches have to consider this difference.

Aged↗

Frequent amplifications and abundant expression of TRIO, NKD2, and IRX2 in soft tissue sarcomas.

Copy number gains and high-level amplifications of the short arm of chromosome 5 are frequently observed in soft tissue sarcomas. To identify genes from this region possibly involved in tumor progression, we analyzed 34 soft tissue sarcomas (10 pleomorphic and 8 dedifferentiated liposarcomas, 6 malignant fibrous histiocytomas, and 10 malignant peripheral nerve sheath tumors (MPNST)) using a DNA microarray including 418 BAC clones representing 99% of chromosome arm 5p. In seven tumors, distinct high-level amplifications were identified affecting four different subregions. From these regions, genes TERT, TRIO, SKP2, FBXO32, NKD2, SLC6A3, IRX2, POLS, FYB, PTGER4, and FGF10 were selected for detailed quantitative expression analysis (RQ-PCR) based on their potential tumorigenic function. Of these, TRIO, coding for a guanidine nucleotide exchange factor, was consistently overexpressed in all cases, while IRX2 and NKD2, both involved in the regulation of developmental processes via the WNT pathway, showed a characteristic expression only in MPNSTs. Detailed nonparametric multidimensional scaling analysis further showed that the expression of TRIO, IRX2, and NKD2 strongly correlated with the gene copy number. In conclusion, we found TRIO, IRX2, and NKD2 frequently affected by high-level amplifications as well as up-regulated in a gene-dosage dependent manner. Thus, these genes represent candidate targets of 5p amplifications in soft tissue sarcomas and might play a crucial role during the progression of this disease.

Adaptor Proteins, Signal Transducing↗

Clinical results of surgery for retroperitoneal sarcoma with major blood vessel involvement.

PURPOSE: The study was conducted to evaluate the clinical results of resection for retroperitoneal soft tissue sarcoma (STS) with vascular involvement. METHODS: The study group consisted of consecutive patients (mean age, 52 years) who underwent surgery for retroperitoneal STS with vascular involvement. The procedures were performed between 1988 and 2004. Vessel involvement by STS was classified as type I, artery and vein; type II, only artery; type III, only vein; and type IV, neither artery nor vein (excluded from the analysis). Patient data were prospectively gathered in a computerized database and retrospectively analyzed. RESULTS: Of 141 patients with retroperitoneal STS, 25 (17.7%) underwent surgery for tumors with vascular involvement. The most common vascular involvement pattern was vein only (type III) at 64%. Arterial and vein (type I) and arterial only (type II) involvement were observed in 16% and 20% of the cases, respectively. STS originating from the vessel wall (primary vessel involvement) was seen in eight patients, and 17 patients had secondary vascular involvement. Resection and vascular repair were done in 22 patients (no vascular repair in three patients due to ligation of the external iliac vein in one patient, and debulking procedures in two). All patients with arterial involvement (type I and II) had arterial reconstruction consisting of aortic replacement (Dacron, n = 3; and expanded polytetrafluoroethylene [ePTFE], n = 2), iliac repair (Dacron, n = 3), and truncal reimplantation (n = 1). The inferior vena cava (6 ePTFE tube grafts, 3 ePTFE patches, 2 venoplasties), iliac vein (1 ePTFE bypass, 1 Dacron bypass, 1 venous patch), and superior mesenteric vein (1 anastomosis, 1 Dacron bypass) were restored in 80% of the patients (n = 16) with either arterial and venous or only venous involvement (type I and type III setting). Morbidity was 36% (hemorrhage, others), and mortality was 4%. At a median follow-up of 19.3 months (interquartile range, 12.8 to 49.9 months) the arterial patency rate was 88.9%, and the venous patency rate was 93.8% (primary and secondary). Thrombosis developed in one arterial and venous (type I) iliac reconstruction due to a perforated sigmoid diverticulitis 12 months after surgery. The local control rate was 82.4%. The 2-year and 5-year survival rates were 90% and 66.7% after complete resection with tumor-free resection margins (n = 10 patients, median survival not reached at latest follow-up). The median survival was 21 months in patients with complete resection but positive resection margins (n = 7) and 8 months in patients with incomplete tumor clearance (n = 8, persistent local disease or metastasis). CONCLUSIONS: Patency rates and an acceptable surgical risk underline the value of en bloc resection of retroperitoneal STS together with involvement of blood vessels. The oncologic outcome is positive, especially after complete resection with tumor-free resection margins. A classification of vascular involvement can be used to plan resection and vascular replacement as well as to compare results among reports in a standardized fashion.

Adolescent↗

Treatment of gastrointestinal stromal tumor with imatinib mesylate: a retrospective single-center experience in Heidelberg.

BACKGROUND: Gastrointestinal stromal tumor (GIST) is the most common mesenchymal neoplasm of the gastrointestinal tract. Surgery has been the only effective therapy. However, many patients still eventually die of disease recurrence. Chemotherapy and radiation therapy have been of limited value. Imatinib mesylate (Glivec) is an orally administered competitive inhibitor of tyrosine kinases associated with the KIT, ABL protein, licensed for the treatment of metastatic GIST since 2002 in Germany. METHODS: We summarized the data of 16 patients with advanced or metastatic GIST treated with imatinib mesylate in palliative and neoadjuvant settings. RESULTS: Overall response was 81%, with no evidence of disease (NED) in 3/16 (19%), partial response (PR) in 9/16 (56%) and stable disease (SD) in 1/16 (6%), whereas 3/16 patients (19%) suffered from progressive disease (PD). Mean follow-up was 18.6 months [range: 4-30]. Mean progression-free survival (PFS) was 17.6 months [range: 0-30], mean overall survival (OS) from initial diagnosis was 32.3 months [range: 5-122]. Most common side effects were periorbital edema and skin rash. CONCLUSION: Imatinib mesylate is well tolerated in a dose of up to 800 mg/day and has significant activity during long- term treatment of patients with advanced or metastatic GIST.

Adult↗

Malignant vascular tumors: clinical presentation, surgical therapy, and long-term prognosis.

BACKGROUND: The aim of this study was to analyze the presentation of, surgery for, and prognosis of malignant vascular tumors (MVTs). METHODS: This was an observational single-center study. Patients who underwent operation for MVTs between 1988 and 2004 were included. Data were gathered prospectively in a computerized registry. RESULTS: Of 568 adult patients with soft tissue malignancies, 43 (7.6%) were treated for MVTs. Twenty-four men and 19 women (median age, 55.3 years) were referred for 30 primary tumors and 13 recurrences. Symptoms were observed in 90.7% of the cases (swelling [37.2%], pain [34.9%], extrusion [11.6%], hemorrhage [7%], weight loss [4.7%], loss of energy [4.7%], impaired function [4.7%], and others [30.2%]). Tumors were located in the extremities (n = 16), trunk (n = 3), abdomen (n = 15), retroperitoneum (n = 7), and thyroid gland (n = 2). Twenty-two (51.2%) angiosarcomas, nine (20.9%) malignant hemangiopericytomas, eight (18.6%) malignant epithelioid hemangioendotheliomas, and four (9.3%) lymphangiosarcomas were seen. The median overall survival after surgery was 21.4 months, with 2-, 5-, and 10-year overall survival rates of 41.5%, 38.3%, and 18.8%, respectively. MVTs of the extremities and trunk and localized disease indicated a better prognosis than abdominal or retroperitoneal MVTs (univariate and multivariate analyses: P = .0122 and P = .0287) and metastasized stages (univariate and multivariate analyses: P = .0187 and P = .0287). CONCLUSIONS: A considerable number of patients with soft tissue malignancies undergo surgery for MVT. Various symptoms and a multilocular occurrence are typical. The course of MVTs is aggressive. Tumor site and stage are important prognostic factors. Surgery is potentially curative, especially for localized disease of the extremities and trunk.

Adult↗

Oncogenetic tree models based on cytogenetic data: new insights into the development of epithelial tumors of the thymus.

Epithelial tumors of the thymus are rare neoplasms typically arising in the anterior mediastinum. There is an ongoing discussion whether thymomas of different histological subtypes form a biological continuum or represent distinct biological entities. To further investigate this question, we performed a statistical analysis of CGH data of 65 previously published cases. Losses of 3p, 6p, 6q, 13q, 16q, and 17p, as well as gains on 1q, were found in at least 10% of the cases. Comparing the data from B2, B3, and C thymomas, we noted an increasing complexity of karyotypes that may be well explained by a sequential order of these types. The frequencies of losses on 16q and 17p show a significant trend with respect to the sequence from B2 to B3 and C thymomas, indicating that these aberrations may be important events in the transition between these tumor types. To identify pathways of genetic development and progression of thymomas, we used oncogenetic tree models representing the dependencies between recurrent chromosomal aberrations. This analysis suggests that gains on the long arm of chromosome 1 occur early in tumor development and are correlated with losses on 6p and 6q. There is a weak correlation with losses on 16q and 17p, which appear to be late events. An independent pathway leads to losses on 3p and 13q, which are closely correlated. Our results indicate that the development of thymomas seems to be in some part a multistep mechanism. Oncogenetic tree models are a helpful means to determine developmental pathways of tumors arising from the same progenitor cell, as shown here for thymomas.

Chromosomes, Human, Pair 16↗

Cystic thymoma.

Thymic cysts are rare lesions located along the anatomical course of the third pharyngeal pouch. While most of the cases represent congenital cysts, they may also be related to neoplasms. We report a case of a micronodular thymoma with lymphoid stroma, which was completely built of small cysts, discuss the pathologic features of this tumor type and review the etiology and other aspects of thymic cysts.

Aged↗

Results of limb-sparing surgery with vascular replacement for soft tissue sarcoma in the lower extremity.

OBJECTIVE: To evaluate limb-salvage surgery with vascular resection for lower extremity soft tissue sarcomas (STS) in adult patients and to classify blood vessel involvement. METHODS: Subjects were consecutive patients (median age, 56 years) who underwent vascular replacement during surgery of STS in the lower limb between January 1988 and December 2003. Blood vessel involvement by STS was classified as follows: type I, artery and vein; type II, artery only; type III, vein only; and type IV, neither artery nor vein (excluded from the analysis). Patient data were prospectively gathered in a computerized database. RESULTS: Twenty-one (9.9%) of 213 patients underwent vascular resections for lower limb STS. Besides 17 type I tumors (81.0%), 3 (14.3%) type II and 1 (4.7%) type III STS were diagnosed. Arterial reconstruction was performed for all type I and II tumors. Venous replacement in type I and III tumors was performed in 66.7% of patients. Autologous vein (n = 8) and synthetic (Dacron and expanded polytetrafluoroethylene; n = 12) bypasses were used with comparable frequency for arterial repair, whereas expanded polytetrafluoroethylene prostheses were implanted in veins. Morbidity was 57.2% (hematoma, thrombosis, and infection), and mortality was 5% (embolism). At a median follow-up of 34 months, the primary and secondary patency rates of arterial (venous) reconstructions were 58.3% (54.9%) and 78.3% (54.9%). Limb salvage was achieved in 94.1% of all cases. The 5-year local control rate and survival rate were 80.4% and 52%, respectively. We observed a 5-year metastasis-free survival rate of 37.7% and found vessel infiltration and higher tumor grade (low-grade vs intermediate grade and high grade tumors) to be negative prognostic factors at univariate and multivariate analysis. CONCLUSIONS: Long-term bypass patency rates, the high percentage of limb salvage, and the oncologic outcome underline the efficacy of en bloc resection of STS involving major vessels in the lower limb. Disease-specific morbidity must be anticipated. The classification of vascular involvement (type I to IV) is useful for surgical management.

Algorithms↗

Prognostic significance of preoperative [18-F] fluorodeoxyglucose (FDG) positron emission tomography (PET) imaging in patients with resectable soft tissue sarcomas.

OBJECTIVE: The objective of this study was to evaluate the prognostic significance of preoperative positron emission tomography (PET) using 2-fluoro-2-deoxy-D-glucose (FDG) by calculating the mean standardized uptake values (SUV) in patients with resectable soft tissue sarcomas (STS). SUMMARY AND BACKGROUND DATA: FDG-PET might be used as an adjunctive tool (in addition to biopsy and radiologic tomography) in the preoperative prognostic assessment of resectable STS. METHODS: A total of 74 adult patients with STS underwent preoperative FDG-PET imaging with calculation of the SUV. Clinicopathologic data and the SUV were analyzed for an association with the clinical outcome. The first and the third quartiles of the SUV distribution function were used as cutoff values (1.59 and 3.6). Survival was estimated by the Kaplan-Meier method. Univariate and multivariate analyses were performed using log-rank test and the Cox proportional hazards regression model. RESULTS: In 55 cases, STS were completely resected (follow up 40 months): 5-year recurrence-free survival rates in patients with SUV <1.59, 1.59 to <3.6, and > or =3.6 were 66%, 24%, and 11%, respectively (P = 0.0034). SUV was a predictor for overall survival (5-year rates: 84% [SUV <1.59], 45% [SUV 1.59 to <3.6], and 38% [SUV > or =3.6]; P = 0.057) and local tumor control (5-year rates: 93% [SUV <1.59], 43% [SUV 1.59 to <3.6], and 15% [SUV > or =3.6]; P = 0.0017). By multivariate analysis, SUV was found to be predictive for recurrence-free survival. The prognostic differences with respect to the SUV were associated with tumor grade (P = 0.002). CONCLUSION: The semiquantitative FDG uptake, as measured by the mean SUV on preoperative PET images in patients with resectable STS, is a useful prognostic parameter. SUV with cutoff values at the first and the third quartiles of the SUV distribution predicted overall survival, recurrence-free survival, and local tumor control. Therefore, FDG-PET can be used to improve the preoperative prognostic assessment in patients with resectable STS.

Adult↗

Chromosomal imbalances in sporadic neuroendocrine tumours of the thymus.

Neuroendocrine (carcinoid) tumours of the thymus are rare neoplasms characterized by a highly malignant clinical behavior. Some of these tumors are associated with MEN1. In this study we evaluated 10 cases of sporadic thymic neuroendocrine tumours using immunohistochemistry and comparative genomic hybridization (CGH). All tumours showed a diffuse expression of neuron specific enolase (NSE) and synaptophysin. Chromosomal imbalances were detected in 8/10 cases, the most frequent gains were seen on chromosome Xp (3/10 cases), 7p, 7q, 11q, 12q, and 20q (2/10 each), losses were most frequently detected at 6q (5/10 each), 6p (3/10 each), 4q (3/10 each), 3p, 10q, 11q and 13 q (2/10 each). These CGH data show a degree of overlap with chromosomal imbalances commonly observed in advanced thymomas.

Adult↗

Comparable transforming capacities and differential gene expression patterns of variant FUS/CHOP fusion transcripts derived from soft tissue liposarcomas.

The chromosomal translocation t(12;16)(q13;p11) is a common genetic alteration in myxoid and round-cell liposarcomas. It results in transcription of various chimeric FUS/CHOP fusion transcripts that encode different oncogenic proteins. Recent reports suggest that these may have different neoplastic transformation activities. To audit this hypothesis, we transfected expression plasmids for the two major variant FUS/CHOP transcripts I and II in NIH 3T3 cells and determined the number of outgrowing foci as well as their growth potential in soft agar. In addition, we compared tumour growth in nude mice upon subcutaneous injection of the respective transfectants. No significant differences in transformation assays in vitro and in vivo were observed, suggesting that both variant transcripts confer comparable transforming activities. The histopathological picture of tumours derived from both cell populations resembles high-grade spindle cell sarcomas. This suggests that both FUS/CHOP variants cause similar patterns of differential gene expression. This hypothesis was confirmed by mRNA-expression profiles of the respective cell clones. Strong overexpression of the pentaxin-related gene (PTX), the osteoblast-specific factor 2 (osf-2), the basic Kruppel-like factor (bklf), the leucoprotease inhibitor, and the cyclophilin B were observed in both types of FUS/CHOP-transfected cell clones. Taken together, our data suggest that different FUS/CHOP variants cause transformation of mesenchymal cells via the same pathways with comparable efficacy.

Animals↗

Gastrointestinal stromal tumours and their response to treatment with the tyrosine kinase inhibitor imatinib.

Gastrointestinal stromal tumours (GISTs), the most common mesenchymal tumours of the digestive tract, are largely resistant to chemo- and radiotherapy. They are currently defined by their overexpression of the KIT receptor tyrosine kinase (CD117), a member of the family of receptor tyrosine kinases (RTKs), and exhibit KIT mutations in more than 85% of cases. Additionally, in more than one-third of KIT wild-type GISTs, mutations of platelet-derived growth factor receptor alpha (PDGF-R alpha), which also belongs to the family of RTKs, were recently found. Since these data indicate that uncontrolled RTK signalling may be implicated in the pathogenesis of GISTs, RTKs and the activated downstream signalling cascades are attractive targets in the therapy of these tumours. Imatinib is a small-molecule inhibitor that selectively blocks the activity of the PDGF-R, ABL and KIT receptor tyrosine kinases by competitive binding to the adenosine triphosphate binding site of their catalytic domains. We herein review the molecular pathological, preclinical and clinical data that identify imatinib as a valuable new agent in the treatment of GISTs.

Animals↗