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C Stroszczynski

Publications and source records attributed to C Stroszczynski.

At least 37 records · Page 2Linked to original sources
PubMed2003

[Morphology of gastrointestinal stromal tumors in advanced stages of the disease: baseline findings before chemotherapy with imatinib].

PURPOSE: Gastrointestinal stromal tumors (GISTs) are rare tumors of the gastrointestinal tract with an increasing detection rate due to improved differentiating methods in current diagnostic pathology. This study evaluates the radiologic characteristics of these neoplasms to discover specific signs leading to an earlier diagnosis. MATERIALS AND METHODS: As part of a randomized phase III clinical trial of the European Organization for Research and Treatment of Cancer (EORTC), 72 patients with advanced stage GIST were treated with the selective tyrosine-kinase-inhibitor imatinib (Glivec, Novartis, Switzerland). For initial staging, 60 patients underwent MRI and 12 patients underwent CT. RESULTS: GISTs are mesenchymal tumors that grow submucosally and exophytically and become multiple, nodular or ovoid in the advanced stage. The predominant findings are peripheral solid structures with strong contrast enhancement and a central necrosis. Metastases are primarily located in the liver, where they appear as oval or round, sharply delineated solitary lesions with central necrosis. CT demonstrates the primary tumors and local recurrences as nearly isodense with the liver. On MRI, the lesions are hypointense on T 1 -weighted sequences and hyperintense on T 2 -weighted sequences, compared to the liver. CONCLUSION: Immunopathology now enables the exact histologic separation of GISTs from other mesenchymal tumors. The radiological morphology is not sufficiently specific to differentiate GISTs from other mesenchymal tumors. In view of new therapeutic options, cognizance of their typical manifestations is of increasing importance for radiologists.

Adult↗
PubMed2003

[Use of SPIO-enhanced T1- and T2-weighted images for the differentiation of liver lesions: an ROC analysis].

PURPOSE: The superparamagnetic iron oxide (SPIO) Resovist is a contrast media with shortening of both T(1) and T(2) relaxation time. This study evaluates the impact of SPIO-enhanced T(1)- and T(2)-weighted images for the differentiation of liver lesions. MATERIALS AND METHODS: SPIO-enhanced MRI examinations (1.5 T, Symphony Quantum) of 61 patients were analyzed. Thirty-seven patients had malignant liver lesions (metastases n = 32, HCC n = 5) proven by biopsy or laparotomy, 11 patients had benign liver lesions (FNH n = 2, hemangiomas n = 4, benign cysts n = 5, normal liver on laparoscopy n = 13). After unenhanced T(1)- and T (2)-weighted imaging, a bolus injection of 1.4 ml SPIO (Resovist) was given, followed by T(1)-weighted imaging at 20 s, 60 s, and 5 min and T(2)-weighted imaging at 10 min post injection. A score from 1 (benign) to 5 (malignant) was used by three blinded radiologist for the ROC analysis of the unenhanced T(1)-/T(2)-weighted images (set 1) and of the combinations of unenhanced T(1)/T(2)-weighted and SPIO T(1)-weighted images (set 2), unenhanced T(1)/T(2) and SPIO T(2)-w images (set 3) and all images (set 4). RESULTS: The accuracy of plain MRI (set 1: 56 %) was increased by SPIO-enhanced T(1)-weighted images (set 2: 81 %) and SPIO-enhanced T(2)-weighted images (set 3: 90 %). Best results were obtained using unenhanced T(1)-weighted, unenhanced T(2)-weighted and both SPIO T(1)-weighted and T(2)-weighted images (set 4: 93%). The accuracy of predicting histopathologic diagnosis was 91%. CONCLUSION: For the differentiation of liver lesions, SPIO-enhanced T(2)-weighted images had a greater impact on the accuracy of MRI than T (1)-weighted images, but SPIO-enhanced T(1)-weighted images provided additional information in some patients and should not be deleted.

Adult↗
PubMed2003

Double contrast MRI of thermally ablated liver metastases.

PURPOSE: To investigate the ability of double contrast MRI (enhancement with iron oxide and gadopentetate dimeglumine) to increase the difference in contrast between various tissues after thermal ablation of liver metastases. MATERIALS AND METHODS: 12 patients were imaged after MR-guided laser-induced thermotherapy (LITT). Imaging was performed with a 1.5T MR system. Nonenhanced, iron oxide-enhanced and double contrast images were acquired using T (1)-weighted GRE and T (2)-weighted TSE sequences. Iron oxide imaging was performed 10 min after injection of 1.4 ml ferucarbotran (Resovist(R), Schering AG Berlin, Germany) and double contrast imaging 60 sec after the additional injection of 0.1 mmol/kg body weight gadopentetate dimeglumine (Magnevist(R), Schering AG Berlin, Germany). Qualitative and quantitative assessment was performed on induced necroses, residual or recurrent tumor tissue and metastatic tissue untreated at the time of the study. RESULTS: Iron oxide-enhanced T (1) GRE images demonstrated the highest contrast between ablated hyperintense tissue and iron accumulating and resultant hypointense liver parenchyma. Due to Gd enhancement, double contrast T (1)-weighted GRE images displayed the highest change in signal intensity in vital tumor tissue compared to ablated tissue and iron oxide accumulating liver parenchyma (p < 0.01). CONCLUSIONS: First observations indicate that LITT of hepatic metastases can be better followed with double contrast MRI, which displays increased contrast due to Gd enhancement of perfused tumor tissue and signal intensity loss in iron oxide accumulating hepatic parenchyma. Induced necrosis does not change its signal intensity at all after injection of iron oxide and Gd-containing contrast media.

Aged↗
PubMed2003

[Flexible applicator systems for radiofrequency ablation (RFA) of hepatic tumors].

PURPOSE: To report our experience with flexible applicators in radiofrequency ablation (RFA) of hepatic tumors. MATERIALS AND METHODS: In 6 liver tumors in 6 patients, a flexible RFA-applicator system (RITA StarBurst FLEX, RITA Medical Systems, Mountain View, CA, USA) was placed under CT guidance. The Seldinger technique with an 11G access system (RITA StarBurst Access) was used to place the application system into the liver. Before and within a week after the ablation, all tumors were investigated with contrast-enhanced MRI. RESULTS: The Seldinger technique accommodated the placement of a thin 17.5-gauge needle for the initial puncture, enabling easy adjustment of the position of the needle. The flexible applicator of the RFA system could be placed in 4.5 (+/- 1.8) minutes on average. CONCLUSION: Flexible applicators facilitate CT-guided RFA and can be placed using the Seldinger technique.

Carcinoma, Hepatocellular↗
PubMed2002

Resection and local therapy for liver metastases.

In 30-50% of patients the liver is a preferred site of distant disease for many malignant tumours. Due to the high incidence, most of the available data relate to metastases arising from colorectal primaries. Surgical resection is at present the only treatment offering potential cure. The achievable 5-year survival rate is 30%. However, only 10-15% of patients with colorectal liver metastases can undergo potentially curative liver resection. Therefore, accurate staging is an important prerequisite in selecting patients who would benefit from surgery. Recurrence of hepatic metastases after potentially curative resection occurs in up to 60% of the cases. Results demonstrate that re-resection of liver metastases can provide long-term survival rates in a carefully selected group of patients without extrahepatic disease. Because of the high rate of recurrences following an apparently curative resection several authors investigated the use of adjuvant chemotherapy (systemic, intraportal, and hepatic arterial infusion). Until recently none had shown effectiveness. Pre-operative chemotherapy seems to be a promising approach in patients with liver metastases initially considered unsuitable for radical surgery. Recently, neoadjuvant chemotherapy has been proposed as an alternative approach to conventional surgery as initial management with the aim of improving the results in resectable liver metastases. Interventional strategies (ethanol injection, cryosurgery, laser-induced thermotherapy, radio-frequency ablation) and combined modalities (surgical/interventional) are additive methods which may help to improve treatment results in the future.

Antineoplastic Agents↗
PubMed2002

[Laser-induced thermotherapy (LITT) for malignant liver tumours: the role of sonography in catheter placement and observation of the therapeutic procedure].

AIM: Evaluation of sonography in the placement of catheters for laser-induced thermotherapy (LITT) as well as for the observation of the therapeutic procedure in cases of malignant liver tumours. METHODS: Following the placement of 1-4 LITT applicators, 18 patients with malignant liver tumours (recurrence of hepatocellular carcinoma n = 5, metachronous liver metastases n = 13) were examined by ultrasound to determine the position of the applicators as well as the sonographic visualisation of the respective lesion. The laser treatment procedure was also observed sonographically. As standard reference method for the documentation of thermally induced necroses we used magnetic resonance tomography 24-48 hours after the procedure. RESULTS: The tip of the applicator could be localised in all cases, and the position of the applicator relative to the lesion could be directly visualised in 78% of cases. The hyperechogenic thermal effect during LITT had a median size of 4.5 cm, thus proving to be significantly larger than the actual necrosis induced (p < 0.01). The sonographic observation of the procedure identified 8/10 primarily incomplete ablations which were then treated again immediately after correction of the position of the applicators. CONCLUSION: Continuous sonographic observation of the procedure of LITT can yield important additional information.

Adult↗
PubMed2001

[Influence of positron emission tomography on surgical therapy planning in recurrent colorectal cancer].

The advantages of PET are high sensitivity and specificity for the detection of local tumor relapse, especially in comparison with conventional imaging techniques. Furthermore, there is an additional value of FDG-PET for the detection of tumor manifestations associated with a tumor marker (e.g. serum CEA) increase without suspicious findings in other diagnostic procedures. The methodological advantage of a whole-body examination further improves the detectability of distant metastases. Thus, FDG-PET may induce a change in the therapeutic concept in recurrent colorectal cancer in approximately 30% of cases, concerning the indication for surgery as well as the use of multimodal surgical concepts. By means of the metabolic functional approach FDG-PET offers the possibility of therapy monitoring. This enables very early and more specific indication of response to preoperative therapies or of the presence of residual disease after surgical tumor resection or interventional tumor ablation of metastases or recurrences. PET using new tracer molecules demonstrates an additional advantage of the technique regarding the determination of the micromilieu of a tumor (vascularity, proliferation) compared with all other non-invasive diagnostic methods. This opens up new possibilities to optimize surgical therapy planning and prognostic evaluation.

Adult↗
PubMed2001

[Laser-induced thermotherapy (LITT). Use of round and pointed laser applicator systems--initial results].

PURPOSE: To assess the advantages and disadvantages by using round and sharp laser application systems during laser-induced thermotherapy. METHOD: 6 in vitro examinations were performed and 12 patients with liver metastases of colorectal carcinoma were treated with laser-induced thermotherapy. All lesions were closely localised to the diaphragm, liver capsule and large intrahepatic vessels. Five patients were treated with the sharp and 7 patients with the round applicator system. After CT-guided insertion of the catheter system into the metastasis laser therapy was performed under MRI control (approx. 25 W, 20 min). RESULTS: Reduction of the distance between the laser applicator and rounded laser catheter tipp (approx. 0.5-1 cm) leads to better placement of the laser applicator in metastases located near the diaphragm, liver capsule and large intrahepatic vessels. Improved therapy results due to complete ablation of metastases were obtained. All patients treated with the round system had complete ablation of metastasis. In 3 of 5 patients treated with the sharp system, MRI control 2 days after therapy showed a residual tumour margin close to the diaphragm or to an intrahepatic vessel. DISCUSSION: Improved ablation can be obtained by closer placement of a round laser catheter in liver metastasis located near the diaphragm, liver capsule and large intrahepatic vessels.

Adult↗
PubMed2001

[Radiological-guided liver-port implantation: Evaluation, technical approach, interventional procedure and follow up].

UNLABELLED: Radiological-guided liver-port implantation: Evaluation, technical approach, interventional procedure and follow up. PURPOSE: Description of evaluation, technical approach, interventional procedure and follow up of radiological-guided liver-port implantation. METHOD: Percutaneous implantation of a liver-port system was performed in twelve patients through a transfemoral approach and in one patient via the superficial epigastric artery after surgical exploration. In four patients we used port systems which are accessible via ventral puncture. Strecker-port systems were implanted in the remaining nine patients. RESULTS: The liver-port implantation was technically successful in all cases. No dislocation of the distal catheter tip, no thrombosis of the hepatic or splenic artery, no leakage near connections of the catheters or connections of catheter and port system and no thrombosis of the femoral arteries were observed. Correction of a kink in the catheter was performed in one patient. Another patient showed prolonged healing of the subcutaneous pocket. CONCLUSIONS: Interventional liver-port implantation is a safe procedure and leads to good clinical results. From the view of the radiologist the Strecker-system shows a good performance. The approach via the superficial epigastric artery demands excellent interdisciplinary cooperation.

Angiography↗
PubMed2001

Histopathological correlation to MRI findings during and after laser-induced thermotherapy in a pig pancreas model.

RATIONALE AND OBJECTIVES: To investigate whether percutaneous laser-induced thermotherapy (LITT) with continuous magnetic resonance (MR) monitoring of thermal effects within the pancreas is feasible in a porcine model. METHODS: Laser applicators were placed in the pancreas of 15 female pigs. A temperature-sensitive (thermo--fast low-angle shot) sequence was used for continuous monitoring of thermal effects during LITT at 1.5 T. Follow-up MR images were acquired, the pigs were observed for 7 days, and then a pathological examination was performed after sacrifice. RESULTS: Continuous MR monitoring visualized thermal effects in pancreatic tissue and thermal damage of the spleen (n = 1), the left kidney (n = 1), and peripancreatic fat (n = 4) but missed the thermal damage of the duodenum (n = 2). Thermal-induced lesions (10--32-mm diameter) were clearly visualized on contrast-enhanced T1-weighted images. CONCLUSIONS: Laser-induced thermotherapy of pancreatic tissue was feasible in this porcine model, and online monitoring was practicable. Further studies are necessary to increase the accuracy of online MR imaging of thermal effects.

Amylases↗
PubMed2001

[MRI in the diagnosis of tumors of the shoulder girdle area].

The aim of the study was to estimate the value of MRI for evaluation tumors of the shoulder girdle. We diagnosed respectively 13 patients with lesions in the shoulder region. The imaging has been done with a "Magnetom SP 63" (Siemens, Erlangen, Germany). The protocol consisted of T1- and T2-based SE-sequences in axial slice orientation, T1-based imaging in coronary respectively in sagittal slice orientation as well as T1-based sequences after application of contrast medium. The evaluation of the tumor expansion within the soft tissue was possible. The exact diagnosis in some individual cases--neurinoma, cyst of the synovia--could be found by MRI. Estimation of the dignity in the case of infiltrative growth was possible in most cases. To assess the exact type of tumor was often difficult. Especially the dignity of the cartilaginous tumors could not be precisely described.

Acromion↗
PubMed2001

[Multi-slice spiral CT: 3D CT angiography for evaluating therapeutically relevant stenosis in peripheral arterial occlusive disease].

PURPOSE: Evaluation of 3D multislice CT angiography for the assessment of relevant stenoses of pelvic arteries and arteries of the lower extremity in patients with peripheral artery occlusive disease compared to digital subtraction angiography. METHOD/MATERIALS: For this study we examined 31 patients with peripheral artery occlusive disease. All patients received a multislice helical CT angiography and arterial digital subtraction angiography. Multislice CT angiography was performed with a Somatom Plus 4 Volume Zoom (Siemens, Erlangen, Germany). After test bolus injection of 20 ml Ultravist 370 (Schering AG, Berlin) additional 150 ml were applied with a flow rate of 3 ml/sec and a scan delay between 20-35 sec depending on individual blood circulation time. Collimation was 4 x 2.5 mm with a pitch of 6. Reconstructed slice thickness was 3 mm. 3D reconstructions of arteries of pelvic and lower extremity arteries were performed in volume rendering technique on a 3D Virtuoso workstation (Siemens, Erlangen). RESULTS: For the assessment of therapeutically relevant stenoses (over 50% reduction of luminal diameter) multislice CT achieved the following results compared to conventional angiography for the diagnosis of stenosis: sensitivity of 86%, specificity of 86% and an accuracy of 72%. CONCLUSIONS: Multislice helical CT angiography of pelvic arteries and arteries of the thigh represents a reliable means for the detection of relevant stenoses in patients with peripheral occlusive artery disease.

Adult↗
PubMed2000

MRI in decompression illness.

We report a case of decompression illness in which the patient developed paraparesis during scuba diving after rapid ascent. MRI of the spine revealed a focal intramedullary lesion consistent with the symptoms. The pathophysiological and radiological aspects of spinal decompression illness are discussed.

Adult↗
PubMed2000

A phase II trial of gemcitabine in combination with 5-fluorouracil (24-hour) and folinic acid in patients with chemonaive advanced pancreatic cancer.

BACKGROUND: Gemcitabine (Gemzar) and 5-fluorouracil (5-FU) plus folinic acid (FA) both have proven activity in the treatment of patients with advanced pancreatic cancer. The present study was initiated to investigate the efficacy of gemcitabine in combination with 5-FU-FA. PATIENTS AND METHODS: Thirty-eight patients, median age 60 years (range 34-70) with inoperable, stage IV, pancreatic cancer were enrolled into the study and treated on an outpatient basis. All except one patient received at least one cycle of treatment with gemcitabine (1000 mg/m2), followed by FA (200 mg/m2) and 5-FU (750 mg/m2) administered as a 24-hour continuous infusion on days 1, 8, 15 and 22 of a 42-day schedule. No patient had received prior chemotherapy or radiotherapy. All 38 patients were assessed for efficacy, toxicity and time to progressive disease. RESULTS: Two patients (5%), achieved a partial response and thirty-four patients (89%) achieved stable disease. There were two early deaths (< or = 4 weeks). The median time to progression was 7.1 months (range 0.4-18.1+; 95% confidence interval (95% CI): 5.3-7.9 months). Three patients had a progression-free interval of greater than 12 months and 12 of 38 patients (32%) survived longer than 12 months. The median overall survival was 9.3 months (range 0.5-26.5; 95% CI: 7.3-13.0 months). The incidence of grade 3 and 4 toxicities was low. CONCLUSIONS: The combination of gemcitabine and 5-FU-FA is active and well tolerated and seems to offer an improvement in progression-free interval over both gemcitabine monotherapy and 5-FU-FA therapy.

Adult↗
PubMed2000

[Fusion of CT and PET data: methods and clinical relevance for planning laser-induced thermotherapy of liver metastases].

AIM: Catheter-placement in liver metastases is difficult when the lesions are not visible on plain images. We evaluated the use of image fusion using CT and PET data, providing information on anatomy and liver lesions, respectively. METHODS: Plain CT of the liver and whole body FDG-PET were performed in 28 patients with colorectal carcinoma in preparation for laser-induced thermotherapy. Fusions of image data and 2D-visualisation were performed and evaluated with regard to quality of the registration, number of detected lesions and influence of the procedure on laser-induced thermotherapy. Image fusion was performed using an algorithm which was developed by our group. RESULTS: 84 focal liver lesions were visible on CT, 107 on PET images. This means that CT guided catheter placement would have to be performed "blindly" in 23 lesions. In 6 patients previously unknown extra-hepatic tumor deposits were seen on PET images (local recurrence, 2 extrahepatic metastases, 2 second primaries). CONCLUSION: Hot spots from metastases, which are difficult to locate on PET images alone, may be identified on images generated by fusion of CT and PET data. These images facilitate an interventional approach to liver lesions which are not visible on plain CT. As PET allows for whole body screening, it helps identifying patients who would not profit from laser-induced thermotherapy.

Algorithms↗
PubMed2000

[Imaging of intra-arterial hepatic port catheter systems by power-doppler sonography using contrast media--preliminary results].

AIM: This study was designed to determine whether intra-arterial hepatic port catheter systems can be adequately detected by contrast-enhanced power-Doppler sonography. METHOD: 15 patients with a liver port system were investigated before chemotherapy. Examinations were performed with short bolus injections of the contrast medium Levovist in addition to angiographic imaging. RESULTS: Liver port systems were easily detected by the contrast-enhanced power-Doppler method. In 11 out of 15 patients a correct flow of the contrast medium via the port system was seen with both examination methods. One partially occluded hepatic artery was not identified by power-Doppler despite correct flow of the contrast fluid. In one of three patients showing an incorrect flow of the contrast medium the blood circulated primarily through the splenic artery due to a dislocation of the catheter tip. Circulation through both the hepatic and the splenic arteries was shown in a second patient and an occluded right hepatic artery was demonstrated in a third. All these findings were observed with both examination techniques. CONCLUSION: Power-Doppler sonography provides a reliable image of the port catheter system. This method can be used as a follow-up procedure to determine the state of arterial hepatic circulation during chemotherapy.

Aged↗