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Csaba Tóth

Publications and source records attributed to Csaba Tóth.

16 recordsLinked to original sources
PubMed2006

Laser guiding for GeV laser-plasma accelerators.

Guiding of relativistically intense laser beams in preformed plasma channels is discussed for development of GeV-class laser accelerators. Experiments using a channel guided laser wakefield accelerator at Lawrence Berkeley National Laboratory (LBNL) have demonstrated that near mono-energetic 100 MeV-class electron beams can be produced with a 10 TW laser system. Analysis, aided by particle-in-cell simulations, as well as experiments with various plasma lengths and densities, indicate that tailoring the length of the accelerator, together with loading of the accelerating structure with beam, is the key to production of mono-energetic electron beams. Increasing the energy towards a GeV and beyond will require reducing the plasma density and design criteria are discussed for an optimized accelerator module. The current progress and future directions are summarized through comparison with conventional accelerators, highlighting the unique short-term prospects for intense radiation sources based on laser-driven plasma accelerators.

Journal Article↗
PubMed2006

[Surgical aspects of breast cancer screening at our hospital].

In addition to discussing effectiveness of breast cancer screening initiated within the National Public Health Programme, the problem of how to treat non-palpable, early invasive and in situ breast cancer (DCIS) is considered. The theoretical issue of the sentinel lymph node and its impact on biopsy practice have also been dealt with. In the authors' region, screening was introduced in 1999 and after a short break has been continued since 2002. Patient data of three periods, each of two years, each with ten years' interval (1982-1983, 1992-1993, 2002-2003) have been analysed. Changes in the number of surgical operations and tumour size, incidence of in situ cancer, lymph node involvement and distribution of types of surgery have been studied. Biopsy of the sentinel lymph node has been applied since May, 2003 (with 45 biopsies performed until 31 December, 2004). The number of persons participating in the screening programme has gradually increased, the number of surgical operations because of breast cancer increased from period to period. Size of the detected tumours has decreased, the percentage of non-palpable cases has been significant (445 surgical interventions during the years 2002-2004: surgery: 19%). The proportion of DCIS has increased to nearly four times as compared to data of years immediately preceding the era of screening (1993-1998: 11 cases, 2%; 1999-2004: 62 cases, 7.5%). Specificity of sentinel lymph node biopsy was 90%, with a sensitivity of 65%. The proportion of breast saving surgery has increased above 50%. The authors regard screening as successful, in their opinion, its benefits cannot be questioned, in spite of some controversial issues. As to the treatment of non-palpable, early invasive cancer, they underline the importance of preoperative evaluation--cytology, core biopsy--and establishing dignity. The issues of localisation--wire hook marking--and histological processing--large blocks--have also been dealt with. In spite of the fact that the risk for potential malignancy of DCIS lesions has not yet been fully clarified, adequate treatment is indicated; the authors take stand on the issues of indication for surgery, postoperative radiotherapy and use of Tamoxifen. Indications and contraindications of sentinel lymph node biopsy have been summed up.

Adult↗
PubMed2005

Prostate cancer underlying acute, definitive dermatomyositis: successful treatment with radical perineal prostatectomy.

The idiopathic inflammatory myopathies are systemic autoimmune diseases characterized by chronic inflammation leading to progressive weakness of the proximal muscles. In 7-66% of cases of adult dermatomyositis different malignant tumours can promote the difficult cascade mechanisms at the cell level, leading to rapid weakness of skeletal muscles [1]. We report on a patient with all characteristic signs of acute, severe dermatomyositis associated with a low-grade, low-stage prostate cancer cured by radical perineal prostatectomy.

Adenocarcinoma↗
PubMed2005

[The place of estramustine in the treatment of prostate cancer].

INTRODUCTION/AIMS: Prostate cancer is a dynamic disease. Androgen ablation is palliative, and does not cure advanced prostate cancer. The hormone-sensitive cells die, and the hormone-resistant cells come into excess; the disease then progresses, which results in a deterioration of the condition of the patient. The theoretical basis of the curing strategy is the fact that the prostate tumour itself changes during the progression; the molecular determinants of the resistance are present in the varying stages of the disease. The treatment of advanced prostate cancer remains unsolved; it is a well-known fact that a hormone-resistant state develops after the primary treatment forms (androgen withdrawal). The drug of choice for the secondary treatment is estramustine. This can be utilized as monotherapy or in combination. METHODS: In the present study, the results of estramustine treatment of 79 patients with advanced prostate cancer were evaluated. The preparation, known and clinically applied for more than 20 years, was studied in 12 centres. RESULTS: The mean prostate-specific antigen level improved for 6 months, but rose from the 9th month on. The improvement in the subjective condition of the patients paralleled the change in the prostate-specific antigen level. The shortness of the improvement was a consequence of the very high prostate-specific antigen level and the poor general condition. CONCLUSIONS: Estramustine administration is recommended when the prostate-specific antigen level becomes more than doubled following the primary treatment. At a starting prostate-specific antigen level of >100 ng/ml, the treatment leads to total androgen blockade. If the prostate-specific antigen level has not decreased after treatment for 3 months, the secondary strategy is to apply chemotherapy.

Aged↗
PubMed2005

Percutaneous nephrolithotomy in early pregnancy.

We report on an 11-weeks pregnant woman, who under went a percutaneous nephrolithotomy without the use of X-rays during the procedure due to 8-mm left upper ureteric stone. In the available literature, we didn't find any reported case about percutaneous stone removal without the use of X-rays.

Adult↗
PubMed2005

Single-session laparoscopic radical and contralateral partial nephrectomy.

Renal tumor is likely to become one of the most important indications for laparoscopic surgery. We present an old woman, who underwent single-session laparoscopic nephrectomy and contralateral partial nephrectomy due to bilateral kidney tumor. The advantages of simultaneous bilateral intervention are reduced psychological stress, single anaesthesia, less medication, less blood loss, shorter hospital stay and convalescence, and considerable cost-effectiveness.

Aged↗
PubMed2005

Detection of prostate cancer with 11C-methionine positron emission tomography.

PURPOSE: We studied the detection of primary prostate cancer with positron emission tomography (PET) using C-labeled methionine (MET) in patients with increased prostate specific antigen (PSA) levels and repeatedly negative biopsies. MATERIALS AND METHODS: A total of 20 consecutive patients with increased serum PSA and negative repeat biopsies were included in the study. Patient age ranged from 52 to 75 years (average 65). PSA levels ranged from 3.49 to 28.6 ng/ml (average 9.36). Dynamic PET images were obtained from the prostate region using C-labeled MET. Suspicious accumulations of the tracer were anatomically localized using magnetic resonance images and were used as guidance during the next biopsy. RESULTS: PET was positive in 15 (75%) patients, in 7 of whom (46.7%) the next repeat biopsy verified carcinoma. The overall detection rate was 35% (7 of 20) and 46.7% (7 of 15) in the whole group and in the positive PET group, respectively. All 5 of 5 patients with negative MET PET had negative biopsies. CONCLUSIONS: MET PET of the prostate with short dynamic scanning and multicore biopsy is a useful method to ensure a high detection rate of prostate cancer in patients with increased PSA and repeat negative biopsies.

Aged↗
PubMed2005

Simultaneous bilateral percutaneous nephrolithotomy in children.

UNLABELLED: In the paediatric section, two papers relating to the upper urinary tract are presented. The first, from Hungary, describes simultaneous bilateral percutaneous nephrolithotomy in 13 patients, where it was deemed feasible; this is the first such report. Authors from London report on unilateral nephrectomy in patients with nephrogenic hypertension, and found that it was successful in normalising blood pressure in patients with renal hypertension with a normal contralateral kidney. OBJECTIVE: To evaluate the efficacy of removing bilateral kidney stones simultaneously from children, in one session. PATIENTS AND METHODS: Thirteen patients (three girls and 10 boys, 26 kidneys; mean age 8 years, range 3-14) underwent simultaneous bilateral percutaneous nephrolithotomy (PCNL) in the same session, under general anaesthesia, starting with ureteric catheter insertion into both kidneys and using a 26 F adult nephroscope. The mean (range) stone diameter was 2 (1-3.5) cm. Three patients had staghorn stones in one of their kidneys. Ultrasonic disintegration was used; two patients had bilateral and two others unilateral endopylotomy, and one patient had percutaneous suprapubic cystolithotomy in the same session. The mean (range) operative duration was 65 (55-90) min. RESULTS: All patients were rendered stone-free; there was no severe bleeding or any other complication. On one side in one of the patients, a second session was needed because of residual stone. The nephrostomy tubes were removed 3 and 4 days after PCNL and the hospital stay was 6 (1-11) days. CONCLUSION: The advantages of simultaneous bilateral PCNL are reduced psychological stress, one cystoscopy and anaesthesia, less medication and a shorter hospital stay and convalescence, with considerable savings in cost. In experienced hands this method can be used not only in adults but also in children. To our knowledge this is the only report of this technique in children.

Adolescent↗
PubMed2004

Percutaneous nephrolithotomy in children: experience with 138 cases in a developing country.

Our aim was to evaluate our experience with percutaneous nephrolithotomy (PCNL) in children in the Republic of Yemen. Between January 1993 and December 1998, 135 children underwent 138 percutaneous nephrolithotomies in Yemen. The patient's age ranged between 8 months and 14 years (average 8.9 years). There were 117 boys and 18 girls (male:female ratio 6.5:1). The stone size ranged between 124 and 624 mm2 (average 507 mm2). A 26 F adult nephroscope was used. The stone free rate was 98.5% (136 out of the 138 cases). Two patients had clinically insignificant fragments. A second session had to be performed because of residual stone in one patient. No severe intra- or postoperative complications were observed. We conclude that percutaneous nephrolithotomy is a safe and effective method for the treatment of kidney stones in children. It reduces morbidity and hospital stay and thus the cost of treatment. To our knowledge, this is the largest reported series.

Adolescent↗
PubMed2004

Endopyelotomy in childhood: our experience with 37 patients.

PURPOSE: To evaluate our experience and results with endopyelotomy in the pediatric population. PATIENTS AND METHODS: Between 1990 and 2002, we performed percutaneous antegrade endopyelotomy under general anesthesia in 37 children because of ureteropelvic junction (UPJ) stricture. The youngest patient was 4.5 years and the oldest 17 years at the time of the procedure (mean age 11.5 years). One patient had bilateral stenosis; the two sides were operated on separately. After insertion of a 4F ureteral catheter and filling the collecting system with colored contrast material, a middle calix was punctured under fluoroscopic control. The tunnel was dilated to 26F by telescopic metal dilators. After insertion of a 0.035-inch gidewire through the UPJ, all its layers were cut by a cold knife in the dorsolateral direction so that the periureteral fatty tissue could be seen. Finally, the ureteral wound was stented by a 6F to 12F transrenal drain or a double-J catheter, which was removed after 6 weeks. RESULTS: Among the 37 patients, the procedure had to be repeated in 1 because the transrenal drain stenting the UPJ slid back to the renal pelvis. We had to perform open pyeloplasty or nephrectomy in two patients because of bleeding or failed procedure. The average postoperative hospital stay was 6 days. Comparison of the preoperative intravenous urograms with studies performed 1 year after endopyelotomy showed an overall success rate of 89%. All patients are without complaints at the moment. CONCLUSIONS: In experienced hands, endopyelotomy is a safe and effective method for the treatment of UPJ stricture, not only in the adult, but also in the pediatric, population.

Adolescent↗
PubMed2004

[Thymic neuroendocrine tumor: three cases in our practice].

Authors present 3 cases of the thymic neuroendocrine tumor. They describe the diagnosis, the TNM classification, histology, therapy, and prognosis of the disease. In their opinion the TNM and histology classification have adequate prognostic value.

Adult↗
PubMed2003

[Surgical treatment of malignant renal tumors invading the inferior vena cava and right atrium].

Invading the inferior vena cava and right atrium is the most serious, but fortunately not common complication of renal cell carcinoma. Radical nephrectomy with tumor-thrombus extraction is the only way to improve these patients survival. Cardiopulmonary bypass with or without deep hypothermia and total circulatory arrest might be necessary during surgery. Between 1998 and 2003 at the Department of Cardiac Surgery of University of Debrecen, 5 patients, with renal cell carcinoma extending into the right atrium, had radical nephrectomy and thrombectomy. We used cardiopulmonary bypass, in 2 patients in total circulatory arrest, in deep hypothermia. There was no operative death and neurological complications. One patient died 3 years after the operation due to cardiac failure. In average 42 months after surgery, 4 surviving patients are under regular follow up, they have a good quality of life, without recurrence. In our opinion cardiopulmonary bypass and total circulatory arrest, if necessary, gives the best way for surgical resection of renal cell carcinoma extending into the right atrium.

Aged↗
PubMed2002

Comparison of 150 simultaneous bilateral and 300 unilateral percutaneous nephrolithotomies.

PURPOSE: To compare the results, complications, efficiency, and safety of simultaneous bilateral percutaneous nephrolithotomy (SBPN) and unilateral percutaneous nephrolithotomy (PCNL). PATIENTS AND METHODS: We compared the results and complications of 150 SBPNs with those of 300 unilateral PCNLs. All the procedures were performed by one surgeon which provides relatively constant parameters. The success rates, preoperative and postoperative laboratory results, and complications were compared on the basis of stone size and the number of nephrostomy tracks. RESULTS: There were no significant differences between the results and complications of SBPN and PCNL. The SBPN itself did not cause more blood loss than unilateral PCNL. In both groups, the blood loss was in direct proportion to the size of the stones and the number of nephrostomy tracks. After SBPN, kidney function improved >20% in 12.2% of the patients and worsened for more than 3 days in only 4%. Temporary worsening of kidney function occurred in the unilateral procedure group as well (8%), mostly in cases of solitary kidneys or bilateral stones. The SBPN was not more hazardous than unilateral PCNL (complication rate 11.3% v 14.3%, respectively). In both groups, most of the complications were in proportion to the size and difficulties of the stones. CONCLUSION: Simultaneous bilateral percutaneous nephrolithotomy is a safe and advantageous procedure that is not more hazardous than the separate PCNL in cases of bilateral large stone burdens. To our knowledge, these are the largest reported series of these procedures and the only comparative analysis of SBPN and PCNL.

Adolescent↗
PubMed2002

Clinical predictors of early left ventricular thrombus formation in acute myocardial infarction.

OBJECTIVE: Clinical epidemiological and echocardiographic risk factors relating to the development of a left ventricular thrombus were studied retrospectively in patients with acute myocardial infarction. METHODS AND RESULTS: The data on 1833 consecutive patients treated for acute myocardial infarction during a 10-year period were processed retrospectively. Transthoracic echocardiography was performed on each patient 65.0 +/- 5.5 hours after hospital admission. A left ventricular thrombus was detected in 145 patients (7.9%). The patients with acute myocardial infarction and a left ventricular thrombus had significantly lower frequencies of 1) myocardial infarction in their family history (3% versus 11%, respectively), 2) hospital admission within 24 hours from the onset of chest pain (17% versus 50%, respectively), 3) thrombolytic therapy (8% versus 23%, respectively) and 4) current smoking (24% and 35%, respectively) than those without a left ventricular thrombus. In contrast, anterior infarction (81% versus 38%, respectively), left ventricular dilatation (30% versus 19%, respectively), dyskinesis of the left ventricular wall (23% versus 10%, respectively), an aneurysm (22% versus 7%, respectively) and a reduced systolic left ventricular function (ejection fraction < 40%) (28% versus 17%, respectively) were more frequent in the presence of a left ventricular thrombus after myocardial infarction. Multivariate analysis of the results revealed that the presence of anterior myocardial infarction and an aneurysm is associated with significantly increased hazard ratios. On the other hand, early hospitalization and a positive family history of infarction significantly lowered the hazard ratio. The frequency of a left ventricular thrombus was significantly higher in spring and winter. CONCLUSIONS: The results presented in this paper confirm the significant hazard of certain parameters [location of infarction (anterior) and aneurysm] as concerns left ventricular thrombus formation among patients with acute myocardial infarction. Early hospitalization was found to lower the risk of thrombus formation. These echocardiographic and clinical parameters may be useful in the establishment of the individual risk of intracavital thrombus formation and may be of help in everyday medical practice.

Case-Control Studies↗
PubMedDate not supplied

Administration of estramustine in response to changes in the prostate-specific antigen and Karnofsky index in the treatment of prostate cancer.

Androgen ablation is palliative and does not cure advanced prostate cancer. The hormone-sensitive cells die and the hormone-resistant cells overgrow, resulting in disease progression. The drug of choice for secondary treatment is estramustine (Estracyt). The success of the therapy is followed by changes of the prostate-specific antigen level and Karnofsky scale. In the present study, the results of estramustine treatment of 79 patients with advanced prostate cancer in 12 hospitals were evaluated. The mean prostate-specific antigen level improved for 6 months, but rose from the ninth month on. The improvement in the subjective condition of the patients paralleled the change in the prostate-specific antigen level. The short time of improvement was a consequence of the very high prostate-specific antigen level and the poor general condition. Estramustine administration is recommended when the prostate-specific antigen level becomes more than doubled following primary treatment. At a starting prostate-specific antigen level of > 100 ng/ml, the treatment leads to total androgen blockade. If the prostate-specific antigen level has not decreased after treatment for 3 months, the secondary strategy is to apply chemotherapy.

Adenocarcinoma↗