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A Somogyi

Publications and source records attributed to A Somogyi.

At least 37 records · Page 2Linked to original sources
PubMed2001

Mild thrombocytopenia as presenting symptom of type 1 Gauchers's disease.

A young woman was examined for a mild thrombocytopenia which was present for some months. No signs of bleeding had so far occurred. Physical examination was normal except for a moderately enlarged spleen. Laboratory investigations showed a low platelet count. There was no evidence of an autoimmune or hematologic disease. Bone narrow aspirate indicated Gaucher's-like cells raising the suspicion of Gaucher's disease. This was further supported by electron microscopic demonstration of Gaucher's bodies in crista biopsy specimens. However, the definitive diagnosis was obtained by verifying deficient lysosomal glucosylceramide-beta-D-glucosidase activity in peripheral blood leukocytes. Upon the absence of neurologic involvement the patient was typical for the adult-onset or type 1 form of Gaucher's disease.

Adult↗
PubMed2001

[Importance of 3D conformal percutan and brachytherapy treatment planning based on CT and MRI examinations in treatment of oral cavity tumors]

AIM: The importance of 3D conformal percutan and brachytherapy treatment planning based on CT and MRI examinations in treatment of oral cavity tumors. Introducing of the planning procedure and the selection aspects. METHOD: We present the treatment planning based on CT and MRI slices of an oral cavity tumor. The percutan or interstitial boost follow the percutan irradiation of the involved regions and lymph nodes, regarding to the target volume and the critical organs. RESULT: Our ADAC 3D planning system gives us the possibility to add the first line and the boost treatment plans, to determine and compare the dose distribution within the planned target volume and the radiation load of the critical organs. CONCLUSION: The comparative 3D radiation planning system allows higher local dose escalation required for the effective radiation treatment of oral cavity tumors with maximal protection of the surrounding healthy tissues.

Journal Article↗
PubMed2001

[Conformal radiotherapy of maxilla tumors]

PURPOSE: To demonstrate a conventional and a new therapeutic method of 3D treatment planning in maxilla tumors, the process of 3D treatment planning and its significance and to compare these two methods. METHOD: We performed 2D and 3D treatment plans. The ADAC planning system was used in the 3D treatment planning. CT and MRI scans were taken on the target volume and on each scan we demarcated the target volume and the critical organs. The irregular fields were obtained by 3D graphic reconstruction provided by the treatment planning programme. RESULTS: Compared to the conventional treatment planning more favourable dose distribution was obtained within the target volume and the radiation burden of the critical organs was kept under their tolerance doses. CONCLUSION: In conformal 3D treatment planning the shape and size of the irradiated volume are in good conformity with those of the target volume. In this way the radiation burden of the critical organs and adjacent intact tissues can be reduced.

Journal Article↗
PubMed2001

[Modern radiotherapy techniques in the treatment of tumour of the base of tongue]

AIM: To demonstrate the role, the execution and the importance of the computed tomography (CT) based three-dimensional brachytherapy and conformal percutan radiotherapy in the treatment of the advanced tumour of the base of tongue. METHODS: Between January 1993 and June 2000, 27 patients with stage III-IV squamous cell cancers of the base of tongue were treated after 60 Gy percutan irradiation with interstitial, high dose rate brachytherapy (23 patients) or conformal, multi-fields radiotherapy (4 patients) as a boost. The dose of the boost irradiation varied between 12 and 24 Gy. RESULTS: Boost irradiation was well tolerated by the patients. The local tumour control at the mean follow-up period (39 months) was 52%. Using this two treatment methods in case of percutan conformal irradiation 6%, in case of brachytherapy 1.5% of the mandible received the prescribed boost dose. The spinal cord received a maximum of 15%, and 8% of the boost dose, respectively, depending on the two treatment types. CONCLUSION: With the help of these two radiotherapeutic modalities locally higher cumulative dose and better tumour control can be achieved without the higher risk of radiation injury of the surrounding normal tissues and the two most critical organs (medulla, mandible).

Journal Article↗
PubMed2001

[The effect of tumour bed boost on local control after breast conserving surgery. First results of the randomized boost trial of the National Institute of Oncology]

PURPOSE: To evaluate the effect of tumour bed boost on local tumour control (LTC) after breast conserving surgery in a prospective study. METHODS: Between 1995 and 1998, 207 women with early invasive breast cancer who underwent conservative operation were treated by 50 Gy irradiation to the whole breast and then randomly assigned to receive either no further radiotherapy (n=103) or a boost to the tumour bed (n=104) with either 16 Gy electron (n=52) or 12-14.25 Gy high dose rate brachytherapy (n=52). RESULTS: At a median follow-up of 4.25 years the crude rate of local recurrence was 6.7% with and 13.6% without boost. The respective rates of tumour bed relapse were 3.8% vs. 10.7%. The 4 year probability of LTC, relapse-free survival and breast cancer-specific survival was 94.2% vs. 85.1% (p=0.1176), 82.3% vs. 67.2% (p=0.0438) and 84.8% vs. 90.9% (p=0.1111), respectively, in favour of the boost group. Systemic treatments had no significant impact on LTC (88.9% with and 89.6% without systemic treatment, p=0.8858). CONCLUSION: Tumour bed boost decreased the incidence of local and tumor bed relapses with a reduction of 50% and 64%, respectively. Relapse-free survival was improved significantly with boost. However, the influence of boost treatment on breast cancer-specific survival should be tested in further studies. In spite of the higher incidence of late radiation side effects in the boost arm, boost dose is strongly recommended for patients at high risk for local recurrence. The final results of the EORTC trial and other ongoing studies will help to clarify the indication of boost dose according to prognostic subgroups.

Journal Article↗
PubMed2001

The importance of interstitial radiotherapy in the treatment of the base of tongue tumors: a retrospective analysis.

The authors have reviewed their experience with interstitial brachytherapy for the base of tongue cancer with the purpose of introducing treatment strategy and technique and presenting results. Between January 1993 and May 1999 twenty-one patients with primary squamous cell cancer of the base of tongue (T1-4N0-2) were treated by interstitial radiotherapy (RT). Seventeen patients with advanced stage cancer received brachytherapy (BT) boost after 60-66 Gy teletherapy and 4 patients with early stage (T1-2N0) were managed by sole BT after tumor excision and elective neck node dissection in case of positive or very narrow (< 5 mm) margin. High-dose rate (HDR) after-loading unit (Ir-192 source) was used with rigid needles or flexible plastic tubes. The treatment plan was performed by PLATO 3D BT planning system. The mean dose of boost BT or sole BT was 20 Gy (12-24 Gy) and 27 Gy (24-30 Gy), respectively. All treatments were delivered on consecutive days with a twice daily fractionation schedule, except the rigid needle technique (n = 4), where the dose was 12 Gy with a single fraction. After definitive RT of advanced stage disease, the rate of complete or partial remission was 65% (11/17) and 35% (6/17), respectively. At a mean follow-up time of 32 months the local tumor control for the entire patient population was 62% (13/ 21). Five patients (24%) died of local and/or regional failure and sixteen patients (76%) are alive (6 with local and/or regional disease and 10 without evidence of disease). All of the four sole BT treated patients belong to the latter group. The incidence of grade 2 or grade 3 mucositis was 48% and 52%, respectively. To achieve good local control with adequate doses, avoiding surgical morbidity and associated functional loss and to minimize late radiation sequelae, the combination of percutan and interstitial RT seems to be very advantageous in the treatment of the advanced tumor of the base of tongue. For patients with early stage (T1-2N0) cancer, sole postoperative BT of the tumor bed - by positive or very narrow margins - seems to be a feasible option. However, more patients and longer follow-up is required to define the value of sole BT.

Adult↗
PubMed2000

[Alteration of nitric oxide production during arterial myocardial revascularization using extracorporeal circulation. Quantitative measurement of EDNO production by the internal mammary artery bypass graft].

Authors measured the concentration of stable metabolite (NO2: nitrite) of EDNO (endothelium derived nitric oxide) in the internal mammary artery (IMA) bypass graft with the help of a previously reported method (measurement of effective blood flow capacity of the IMA graft in the coronary sinus). Nitrite level in the systemic circulation prior to extracorporeal circulation (ECC)--(68.1 +/- 6.7 mumol/l) was measured, as well as nitrite concentration in the coronary circulation before and after construction of the IMA bypass graft (62.1 +/- 4.19 mumol/l and 50.26 +/- 4.0 mumol/l respectively). Furthermore, nitrite level in the IMA graft free cut end flow was also determined (64.3 +/- 5.9 mumol/l). These data compared to the nitrite levels in the normal plasma (48.1 +/- 5.9 mumol/l) were found to be higher (p = 0.1, ns.), possibly due to the enhanced EDNO production induced by total heparinization. The nitrite concentration in the IMA free cut end flow is similar or slightly higher than that of the native coronary circulation, however, after IMA bypass construction a relative reduction could be measured in the coronary sinus. Authors believe, that this may be related to the reduction of basal EDNO production caused by supernormal pO2 (215 +/- 19 mmHg) during ECC.

Adult↗
PubMed2000

[The role of adhesion molecules in atherosclerosis and diabetes mellitus].

Adhesion of circulating cells to the vascular endothelium is an early step in the development of atherosclerosis. Diabetic patients have a 2-4 fold increased risk for the development of atherosclerosis. Expression of adhesion molecules is increased in diabetes. These molecules may contribute to accelerated atherosclerosis in diabetes. Three main groups of adhesion molecules have been identified: integrins, selectins and members of the immunoglobulin superfamily. The modulation of expression and activity of adhesion molecules may play an important role in the prevention and treatment of atherosclerosis. This article summarises the characteristics and the role of these molecules in atherosclerosis and diabetes.

Animals↗
PubMed2000

[Coronary revascularization on beating heart].

At authors clinic 563 coronary artery bypass graft procedures were done from 1. January 1998 to 15. September 1999. 134 coronary revascularizations were performed from the same surgical team on beating heart using the same surgical technic at normothermia. Out of them, 98 operations were done with and 36 without ECC support respectively. Patients were operated on with this sophisticated technic exclusively during this period. Conversion to cardiac arrest was not necessary in any case. Male/female ratio was 76/58, 84% of the patients suffered from one or more preoperative myocardial infarction. The average bypass number was 2.7/patient. Arterial revascularization was performed in 94%. Postoperative mortality was 2.2% (3 pts). The postoperative inotropic demand, myocardial infarction rate (CK-MB release) and the amount of bleeding was very low. Mean postoperative stay in the ICU decreased to the average of 19 hrs. Patients normally left hospital on the 7th postoperative day. This operative technique--performed by an experienced surgeon--is less invasive for the heart and other organ systems, the incidence of complications can be decreased and the principle of complete revascularization is not compromised.

Coronary Artery Bypass↗
PubMed2000

[CT- and MRI-guided conformal interstitial and external beam radiotherapy of primary brain tumors: prospects in Hungary].

The technical improvements gained over the last decade in neuroradiology and radiotherapy have brought significant theoretical and experimental changes in the treatment of primary glial brain tumours. The follow-up of patients with CT, MRI and isotope diagnostic examinations proves that the relapses take place in the vicinity of the primary site in most cases. Consequently, the conventional large fields or whole brain irradiation techniques have been phased out and the conformal irradiation methods focused on the tumorous targets have gained ground. The exact neuroanatomic projection, the image based 3-dimensional treatment planning methods and the conformal irradiation techniques ensure that only the tumorous or the potentially infiltrated regions become irradiated with maximal protection of the normal brain tissues. The increased protection of the normal tissues makes a dose escalation possible, which may result in the augmentation of the therapeutic benefits. In Hungary both the interstitial and the external beam conformal radiotherapies of the CNS have become accessible in practice over the recent years. In possession of manifold treatment modalities (percutaneous fractionated conformal radiotherapy, stereotactic radiosurgery, high dose rate after-loading and low dose rate interstitial irradiation), it is found necessary to overview the indicative territories, advantages, limitations and possible complications of different interventions. The authors describe the possible routes of further improvements and ways of dose escalation. Nevertheless, it is emphasised that gliomas--with reduced radiosensitivity and high potential to infiltrate the adjacent brain tissues-represent the illness in the whole CNS. It implies that in the future it will probably be necessary to initiate systemic therapeutic modalities in the course of routine treatment strategies in addition to the focused and more effective radiotherapy regimens.

Brain Neoplasms↗
PubMed2000

[An adult form of type-I. Gaucher's disease].

A young woman with no previous history of any diseases was admitted for further evaluation of a mild thrombocytopenia she has had for some months. No signs of bleeding have so far occurred. Physical examination was normal except for a moderately enlarged spleen. Routine investigations showed lower platelet count. There was no laboratory evidence of disease conditions with autoimmune/inflammatory or hematologic origin. Bone marrow aspirate indicated Gaucher's-like cells raising the suspicion of Gaucher's disease. This was further supported by electron microscopic demonstration of Gaucher's bodies (with the characteristic tubular structures) in crista biopsy specimens. However, definitive diagnosis was obtained by verifying deficient lysosomal glucosylceramide-beta-D-glucosidase activity in peripheral blood leukocytes. Upon the absence of neurologic involvement the patient was typical for the adult form or type-1 Gaucher's disease.

Adult↗
PubMed2000

Possibilities of preventing osteoradionecrosis during complex therapy of tumors of the oral cavity.

In recent years, there has been a dramatic increase in the number of tumors of the head and neck. Their successful treatment is one of the greatest challenges for physicians dealing with oncotherapy. An organic part of the complex therapy is preoperative or postoperative irradiation. Application of this is accompanied by a lower risk of recurrences, and by a higher proportion of cured patients. Unfortunately, irradiation also has a disadvantage: the development of osteoradionecrosis, a special form of osteomyelitis, in some patients (mainly in those cases where irradiation occurs after bone resection or after partial removal of the periosteum). Once the clinical picture of this irradiation complication has developed, its treatment is very difficult. A significant result or complete freedom from complaints can be attained only rarely. Attention must therefore be focussed primarily on prevention, and the oral surgeon, the oncoradiologist and the patient too can all do much to help prevent the occurrence of osteoradionecrosis. Through coupling of an up-to-date, functional surgical attitude with knowledge relating to modern radiology and radiation physics, the way may be opened to forestall this complication that is so difficult to cure.

Antineoplastic Agents, Alkylating↗
PubMed2000

Polymorphous low-grade adenocarcinoma of the nasopharynx. Case report and review of the literature.

BACKGROUND: The polymorphous low-grade adenocarcinoma of the nasopharynx is a rare disease. Polymorphous low-grade adenocarcinoma is a minor salivary gland neoplasm which occurs frequently in the mucosa of the soft and hard palates, in the buccal mucosa and in the upper lip. To date this entity has been identified within the oral cavity and only one case within the nasopharynx and some cases in the parotid gland. It has a slow infiltrating growing pattern with frequent perineural invasion and low metastatic potential. CASE REPORT: We report on a patient with non-papillary polymorphous low-grade adenocarcinoma in the nasopharynx which extended intracranially. The patient underwent primary radiotherapy. The CT showed partial response to radiotherapy and the patient is alive 51 months after the diagnosis his state being unchanged. CONCLUSION: The treatment for minor salivary gland tumor is primarily surgical. It is reported that the polymorphous low-grade adenocarcinoma has been known to have poor response to radiotherapy. However, we believe that in addition to its favorable biological behavior, the radiotherapy in this localization may result in longer survival.

Adenocarcinoma↗
PubMed2000

CT-image-based conformal brachytherapy of breast cancer. The significance of semi-3-D and 3-D treatment planning.

PURPOSE: To compare the conventional 2-D, the simulator-guided semi-3-D and the recently developed CT-guided 3-D brachytherapy treatment planning in the interstitial radiotherapy of breast cancer. PATIENTS AND METHODS: In 103 patients with T1-2, N0-1 breast cancer the tumor bed was clipped during breast conserving surgery. Fifty-two of them received boost brachytherapy after 46 to 50 Gy teletherapy and 51 patients were treated with brachytherapy alone via flexible implant tubes. Single, double and triple plane implant was used in 6, 89 and 8 cases, respectively. The dose of boost brachytherapy and sole brachytherapy prescribed to dose reference points was 3 times 4.75 Gy and 7 times 5.2 Gy, respectively. The positions of dose reference points varied according to the level (2-D, semi-3-D and 3-D) of treatment planning performed. The treatment planning was based on the 3-D reconstruction of the surgical clips, implant tubes and skin points. In all cases the implantations were planned with a semi-3-D technique aided by simulator. In 10 cases a recently developed CT-guided 3-D planning system was used. The semi-3-D and 3-D treatment plans were compared to hypothetical 2-D plans using dose-volume histograms and dose non-uniformity ratios. The values of mean central dose, mean skin dose, minimal clip dose, proportion of underdosaged clips and mean target surface dose were evaluated. The accuracy of tumor bed localization and the conformity of planning target volume and treated volume were also analyzed in each technique. RESULTS: With the help of conformal semi-3-D and 3-D brachytherapy planning we could define reference dose points, active source positions and dwell times individually. This technique decreased the mean skin dose with 22.2% and reduced the possibility of geographical miss. We could achieve the best conformity between the planning target volume and the treated volume with the CT-image based 3-D treatment planning, at the cost of worse dose homogeneity. The mean treated volume was reduced by 25.1% with semi-3-D planning, however, it was increased by 16.2% with 3-D planning, compared to the 2-D planning. CONCLUSION: The application of clips into the tumor bed and the conformal (semi-3-D and 3-D) planning help to avoid geographical miss. CT is suitable for 3-D brachytherapy planning. Better local control with less side effects might be achieved with these new techniques. Conformal 3-D brachytherapy calls for new treatment planning concepts, taking the irregular 3-D shape of the target volume into account. The routine clinical application of image-based 3-D brachytherapy is a real aim in the very close future.

Brachytherapy↗
PubMed2000

Evaluation of the dose uniformity for double-plane high dose rate interstitial breast implants with the use of dose reference points and dose non-uniformity ratio.

BACKGROUND AND PURPOSE: To investigate the influence of dwell time optimizations on dose uniformity characterized by dose values in dose points and dose non-uniformity ratio (DNR) and to analyze which implant parameters have influence on the DNR. MATERIALS AND METHODS: Double-plane breast implants with catheters arranged in triangular pattern were used for the calculations. At a typical breast implant, dose values in dose reference points inside the target volume and volumes enclosed by given isodose surfaces were calculated and compared for non-optimized and optimized implants. The same 6-cm treatment length was used for the comparisons. Using different optimizations plots of dose non-uniformity ratio as a function of catheter separation, source step size, number of catheters, length of active sections were drawn and the minimum DNR values were determined. RESULTS: Optimization resulted in less variation in dose values over dose points through the whole volume and in the central plane only compared to the non-optimized case. At implant configurations consisting of seven catheters with 15-mm separation, 5-mm source step size and various active lengths adapted according to the type of optimization, the no optimization, geometrical (volume mode) and dose point (on dose points and geometry) optimization resulted in similar treatment volumes, but an increased high dose volume was observed due to the optimization. The dose non-uniformity ratio always had the minimum at average dose over dose normalization points, defined in the midpoints between the catheters through the implant volume. The minimum value of DNR depended on catheter separation, source step size, active length and number of catheters. The optimization had only a small influence on DNR. CONCLUSIONS: In addition to the reference points in the central plane only, dose points positioned in the whole implant volume can be used for evaluating the dose uniformity of interstitial implants. The dose optimization increases not only the dose uniformity within the implant but also the high dose volume. The optimization on dose points and geometry provides the most uniform dose distribution. The dose non-uniformity ratio can be minimized by selecting the isodose line of the midpoints between the catheters in the whole volume for the dose prescription, but the dose coverage may not be adequate. For a clinically acceptable plan, a compromise should be made between dose non-uniformity and coverage.

Brachytherapy↗
PubMed2000

Circulating plasma endothelin-1, plasma lipids and complications in Type 1 diabetes mellitus.

UNLABELLED: The damage of endothelial integrity is an important step in the atherogenic process. To evaluate the role of circulating endothelin-1 (ET-1) in Type 1 diabetes mellitus (T1DM), plasma ET-1 levels were evaluated in T1DM patients either with (n=9) or without hyperlipidaemia (n=11), or with (n=9) and without (n=11) late diabetic complications, in non-diabetic hyperlipidaemic patients (n=17) and in healthy volunteers. Groups were matched for age, sex and body mass index. RESULTS: Serum total cholesterol and apolipoprotein B were significantly higher in the diabetic group (p<0.05). Plasma ET-1 level was similar in controls and in non-diabetic hyperlipidaemic subjects (5.77+/-1.74 ng/l vs 4.97+/-1.58 ng/l); however, diabetic hyperlipidaemic patients had a significantly higher plasma ET-1 concentration compared to control subjects (6.67+/-2.44 ng/l vs 4.97+/-1.58 ng/l, p<0.05). Diabetic patients with vascular complications had a significantly higher plasma ET-1 concentration than found in diabetic patients without complications (6.99+/-2.17 ng/l vs 4.74+/-1.27 ng/l, p<0.01) and in controls (6.99+/-2.17 ng/l vs 4.97+/ 1.58 ng/l, p<0.01). Patients with diabetic complications also had a significantly higher apolipoprotein B level compared to healthy controls (0.94+/-0.37 g/l vs 0.66+/-0.12 g/l, p<0.005). CONCLUSION: The susceptibility of T1DM patients to the development of atherosclerosis might be attributed to the relationship between elevated lipid levels and ET-1.

Adolescent↗
PubMed2000

Endothelial nitric oxide in diabetes mellitus: too much or not enough?

Vascular complications are the leading cause of increased mortality in patients with diabetes mellitus. Endothelial dysfunction, characterised by impaired endothelium-dependent vasoreactivity, is the first sign of blood vessel damage that precedes morphological changes of the vessel wall. With other factors altered bioavailability of nitric oxide, the most potent endothelium-derived vasodilator, contributes to the changes in vascular tone and integrity. In addition to the impairment of vascular reactivity and permeability, other anti-atherosclerotic functions of nitric oxide are also diminished, which may result in activated monocyte, leukocyte and platelet adhesion to the endothelium, increased platelet aggregation, lipoprotein influx to the subendothelial space and smooth muscle proliferation. Hyperglycaemia-induced increased oxidative stress and impairment of antioxidant defence are suggested to play a role in the pathomechanism of vascular damage, partly by influencing nitric oxide. Both in experimental and clinical Type 1 and Type 2 diabetes mellitus the apparently conflicting data of increased, unaltered or diminished nitric oxide action suggests a complex, time and localisation-dependent alteration of vascular function. The understanding of the mechanisms that lead to diabetic endothelial dysfunction and its early detection are necessary to establish appropriate intervention to prevent irreversible atherosclerotic vessel damage in patients with diabetes mellitus.

Animals↗