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During assessment of the progression of several types of carcinomas, such as cancer of the breast, lungs, prostate or urinary bladder world-wide the presence of circulating cells (micrometastases) in the circulation is followed up. These methods are gradually introduced also in Slovakia. First we tried in the Institute of Medical Biology and Genetics Medical Faculty Comenius University in collaboration with the Urological Clinic of Dérers the Faculty Hospital with policlinic to apply this method in carcinoma of the prostate (CaP). We detected the presence of epithelial prostate cells in the peripheral blood stream of patients with advanced prostate cancer where before secondaries were not detected.
The non-operative treatment of unstable traumatic Anderson's type II odontoid fractures has a high risk potential to develop non-unions. Even after operative stabilization literature reveals non-union rates up to 20%. Acute life threatening complications are tetraplegia and apnoea. Long-term complications induce chronic myelopathy resulting from persistent myeloradicular compression. We report the case of a patient with a 17-year-old post-traumatic pseudarthrosis of the dens axis following conservative treatment of an unstable type II fracture. By that time, the female patient, then 37 years old, was admitted to our hospital with early signs of cervical tetraplegia. After initial reposition and short-term immobilization with a halothoracic vest we performed a ventrodorsal atlantoaxial spondylodesis. Failure of anterior cervical plate stabilization and autologous graft resorption without a solid segmental fusion instigated a secondary surgical intervention. Postoperative therapy-resistant oral wound dehiscence showed an exposed autograft and osteosynthetic material. The reported positive effect of hyperbaric oxygenation on wound healing in problem cases led us to attempt this means of therapy. With a daily exposure to hyperbaric oxygenation, the dehiscence closed within 25 days. As a result of our experience in this case, hyperbaric oxygenation should be considered as a therapeutic option in postoperative complication management in orthopaedic surgery.
Brachytherapy of prostate cancer has become attractive in recent years in Germany. There are several radioactive sources available, which are physically different. Some of them are used as permanent or temporary implants. The permanent sources most frequently used are iodine 125, palladium 103, and gold 198. Iridium is a temporary implant. The techniques used in Germany are low-dose rate (LDR) and high-dose rate brachytherapy, which differ in dose distribution and patient population. The success of prostate cancer brachytherapy depends on patient selection and choosing the right source for the technique used. Best suited for LDR monotherapy is the low-risk patient with a prostate-specific antigen (PSA) level below 10 ng/ml, maximal tumor stage T2b, and a Gleason score of less than 7.
Several experimental data are available regarding the efficacy of the combination of interstitial hyperthermia and conformal radiation therapy. We planned a phase II trial as a member of the special hyperthermia research group of the Deutsche Forschungsgemeinschaft (German Research Society) to determine the efficacy of thermoradiotherapy using interstitial cobalt-palladium thermoseeds in the treatment of patients with localized prostate cancer. Forty-one patients with localized prostate cancer were enrolled in the study between July 1997 and April 2000. The interstitial hyperthermia induced in a magnetic field was applied in six sessions once a week. Conformal three-dimensional radiation therapy was given simultaneously in daily fractions of 1.8 Gy with a total dose of 68.4 Gy. We measured intraprostatic temperatures between 42 degrees and 46 degrees C. No major side effects were observed during the hyperthermia session. The median level of prostate-specific antigen (PSA) decreased from 11.25 ng/ml to 0.88 ng/ml 3 months after treatment and to 0.38 ng/ml 12 months after treatment with a median follow-up of 10 months. The mean prostate volume decreased from 32.6 ml to 26 ml after 3 months of treatment and to 18.5 ml after 12 months. Interstitial hyperthermia is a feasible, well-tolerated procedure in prostate cancer therapy. A significant PSA decrease was observed. Longer follow-up is necessary to determine the efficacy.
At present, biodegradable and biocompatible membranes based on collagen and glycosaminoglycans play an important role in substitutive medicine. Modern biomaterials use a chemically modified collagen-based matrix for implants with programmable biodegradability as a substitute of buccal mucosa, skin, cartilage, etc. Besides the requirements for biocompatibility and biodegradability, the membranes must be also non-toxic. Therefore, cytotoxicity testing of these materials in vitro is an integral part of introducing newly developed types of membranes into clinical practice. As a biological model for the tested COLADERM membrane, cell cultures from human embryonic fibroblasts (B-HEF-2) were used for both cytotoxicity testing as well as in tests to assess the ability of cells to proliferate on this membrane. Along with the ability of cells to grow on the surface and inside the membrane, immunohistochemical examination and scanning electron microscopy (SEM) were performed as well. The obtained results have shown that the COLADERM membrane is non-toxic with suitable structural and biological properties for clinical application as a substitute of buccal mucosa following surgical ablation of malignant tissues from the oral cavity.
OBJECTIVE: Therapies involving a radical operation and radiation treatment for cervical carcinoma in stages I and II are not sufficiently effective in patient subgroups with high risk for recurrence. In recent publications, patients with high risk cervical cancer had with adjuvant simultaneous radio-chemotherapy a better disease free and overall survival but a higher toxicity compared with patients received an adjuvant radiotherapy alone. MATERIAL AND METHODS: 34 patients with at least 2 risk factors for recurrence of cervical cancer were treated with adjuvant chemotherapy after radical hysterectomy. The protocol consisted of 3 cycles of ifosfamide 1.6 g/m2 (d 1-3) and carboplatin (AUC 4, d1) every three weeks. For cell protection 21 patients received amifostine 740 mg/m2 d1-3; this was followed by standard radiation therapy (50.4 Gy percutaneous and high-dose-rate-after-loading for 21 patients, 2 x 5 Gy). The dose determination of the substances and their toxicity were investigated. RESULTS: Patient (p) data: Median age 43 years (range: 25-70); pT1b-2a: n = 22; pT2b: n = 12; pN1: n = 28; pN0: n = 6; G3: n = 10; adeno- and adenosquamous carcinoma: n = 9, G3: n = 10, R1-resection: n = 5. 70.6% of these high-risk patients were disease-free after a median observation time of 40 (18-62) months. Median number of cycles of chemotherapy: 2.8. There was no more dose escalation than carboplatin according to AUC 4 possible. Hematologic toxicity (CTC grading, % of 96 documented cycles): anemia-grade 3-4: 30; -grade 1-2: 10.4; leukopenia-grade 3-4: 13, -grade 1-2: 21.7; alopecia-grade 3: all p.; cerebral neurotoxicity-grade 3-4: 8.3, -grade 1-2; 17.7; diarrhea under radiotherapy-grade 3-4: 2 p., -grade 1-2: 6 p. CONCLUSION: This combined sequential adjuvant therapy was effective and had an acceptable level of toxicity. A phase III study comparing adjuvant sequential chemo-radiotherapy with and without Erythropoeitin to counteract the negative effects of anemia started in Germany in 1999 and had randomized now about 270 patients.
PURPOSE: Four different three-dimensional planning techniques for localized radiotherapy of prostate cancer were compared with regard to dose homogeneity within the target volume and dose to organs at risk, dependent upon tumor stage. PATIENTS AND METHODS: Six patients with stage T1, 7 patients with stage T2 and 4 patients with stage T3 were included in this study. Four different 3D treatment plans (rotation, 4-field, 5-field and 6-field technique) were calculated for each patient. Dose was calculated with the reference point at the isocenter (100%). The planning target volume was encompassed within the 95% isodose surface. All the techniques used different shaped portal for each beam. Dose volume histograms were created and compared for the planning target volume and the organs at risk (33%, 50%, 66% volume level) in all techniques. RESULTS: The 4 different three-dimensional planning techniques revealed no differences concerning dose homogeneity within the planning target volume. The dose volume distribution at organs at risk show differences between the calculated techniques. In our study the best protection for bladder and rectum in stage T1 and T2 was achieved by the 6-field technique. A significant difference was achieved between 6-field and 4-field technique only in the 50% volume of the bladder (p = 0.034), between the 6-field and rotation technique (all volume levels) and between 5-field and rotation technique (all volume levels). In stage T1, T2 6-field and 4-field technique in 50% (p = 0.033) and 66% (p = 0.011) of the rectum volume. In stage T3 a significant difference was not observed between the 4 techniques. The best protection of head of the femur was achieved by the rotation technique. CONCLUSION: In the localized radiotherapy of prostate cancer in stage T1 or T2 the best protection for bladder and rectum was achieved by a 3D-planned conformal 6-field technique. If the seminal vesicles have been included in the target volume and in the case of large planning target volume other techniques should be taken for a better protection for organs at risk e. g. a 3D-planned 4-field technique box technique.
BACKGROUND: The effect of the palliative irradiation of bone metastases was explored in this retrospective analysis. The spectrum of primary tumor sites, the localization of the bone metastases and the fractionation schedules were analyzed with regard to palliation discriminating total, partial and complete pain response. PATIENTS AND METHODS: One hundred seventy-six patients are included in this retrospective quantitative study from April 1992 to November 1993. Two hundred fifty-eight localizations of painful bone metastases were irradiated. The percentage of bone metastases of the total irradiated localizations in our department of radiotherapy in the Charité-Hospital, the primary tumor sites, the localizations and the different fractionation schedules were explored. The total, partial and complete pain response was analyzed in the most often used fractionation schedules and by primary tumor sites. RESULTS: Eight per cent of all irradiated localizations in the observation period were bone metastases. There were irradiated bone metastases of 21 different tumor sites. Most of the primary tumor sites were breast cancer (49%), lung cancer (6%) and kidney cancer (6%). The most frequent site of metastases was the vertebral column (52%). The most often used fractionation schedules were: 4 x 5 Gy (32%), 10 x 3 Gy (18%), 6 x 5 Gy (9%), 7 x 3 Gy (7%), 10 x 2 Gy (5%) and 2 x 8 Gy. The total response rates in this fractionation schedules were 72%, 79%, 74%, 76%, 75% and 72%, the complete response rates were 35%, 32%, 30%, 35%, 33% and 33%. There were no significant differences between the most often irradiated primary tumor sites, the most frequent localizations and the palliation with regard to total, partial and complete pain response. CONCLUSION: There are no differences between the different fractionation schedules with regard to the pain effect of bone metastases. A palliation is ensured in 75% of all cases with a partial response of 42% and complete response of 33%. With regard to pain response these results do not justify a recommendation for a standard fractionation schedule. Current fractionation schedules such as 10 x 3 Gy for 2 weeks or 5 x 4 Gy for 1 week should be used. Another point is the recalcification in the palliative treatment of bone metastases in patients with better prognosis. The recalcification is the basis for stabilization and prevention of fractures. This aspect should be explored in prospective studies.
PURPOSE: Determination of the impact of the filling status of the organs at risk (bladder and rectum) on the uterus mobility and on their integral dose distribution in radiotherapy of gynaecological cancer. METHODS: In 29 women suffering from cervical or endometrial cancer two CT scans were carried out for treatment planning, one with an empty bladder and rectum, the second one with bladder and rectum filled. The volumes of the organs at risk were calculated and in 14 patients, receiving a definitive radiotherapy, the position of the uterus within the pelvis was shown using multiplanar reconstructions. After generation of a 3D treatment plan the dose volume histograms were compared for empty and filled organs at risk. RESULTS: The mobility for the corpus uteri with/without bladder and rectum filling was in median 7 mm (95%-confidence interval: 3-15 mm) in cranial/caudal direction and 4 mm (0-9 mm) in posterior/anterior direction. Likewise, cervical mobility was observed to be 4 mm (-1-6 mm) mm in cranial/caudal direction. A full bladder led to a mean reduction in organ dose in median from 94-87% calculated for 50% of the bladder volume (P < 0.05, Wilcoxon's matched-pairs signed-ranks test). For 66% of the bladder volume the dose could be reduced in median from 78 to 61% (P < 0.005) and for the whole bladder from 42 to 39% (P < 0.005), respectively. No significant contribution of the filling status of the rectum to its integral dose burden was noticed. CONCLUSIONS: Due to the mobility of the uterus increased margins between CTV and PTV superiorly, inferiorly, anteriorly and posteriorly of 15, 6 and 9 mm each, respectively, should be used. A full bladder is the prerequisite for an integral dose reduction.
The authors analysed 1488 cases of spontaneous abortions and stillbirths in Bratislava. They focused on the course of human embryogenesis and the chromosomal constitution. A high mean frequency rate of both developmental defects (14.4%) and chromosomal aberrations (33.6%) was revealed and both were found to be in close relation with the length of gestation. The most severe developmental defects occurred mostly in early stages of human embryogenesis, i.e. in the 1st trimester of gestation.
Invasive hydatidiform mole is a relative rare form of gestational trophoblastic disease (GTD). Most of hydatidiform moles remit after evacuation but some of them have the tendency to invade the myometrium. In some rare cases the trophoblastic tissue can be found in other tissues like lungs, vulva, vagina or broad ligament. The aim of the study was to demonstrate some of clinical, immunohistochemical and DNA analysis findings of a patient with a previous diagnosis of a complete hydatidiform mole.
The hemoglobin (Hb) function is to bear oxygen. Hb is under the exposition of high oxygen concentration in the lung capillaries and it is very slowly oxidated to methemoglobin (MetHb) which is not able to bear oxygen. Enzymatic equipment of erythrocyte protects Fe2+ in HEM in front of the oxidation to Fe3+. It is created 3% of MetHb daily. This action is considered to be autooxidation and it is simultaneously reduced by creation of "complex formation" of MetHb and cytochrome b5. The physiological level of MetHb is 0-2% in the peripheral blood. The MetHb level is enhanced by hereditary impairment of the erythrocyte enzyme apparatus or by changed Hb structure. The patients have enhanced MetHb level in peripheral blood in the range of 1-30%. The only symptom which is created is peripheral cyanosis with neither subjective nor objective difficulties. The patients do not require any treatment. They are very sensitive on receipt of oxidative agents. Occurrence of acquired methemoglobinemia is more frequent in clinical praxis. Administration of oxidative agents is the reason of the disease. The most frequent oxidative agents are sulfones, local anesthetics, enhanced contents of nitrates in vegetables from unsuitable manure soil. The acquired methemoglobinemia causes minimal clinical problems depending on the doses of administered drug and abates after its discontinuation quickly. Only occasionally it causes clinically expressive symptoms. The level above 10% of MetHb causes peripheral cyanosis. The level of MetHb higher than 35% causes general symptoms which are results of the tissue hypoxia. The level about 70% of MetHb is associated with coma and may have fatal outcome. When the level of MetHb is not very high it abates after discontinuation of the administration of causative drug. In the case of high level of MetHb the drug of choice is administration of hyperbaric oxygen, methylene blue, ascorbic acid intravenously or riboflavin in high doses. In the case of deficit of glucoso-6-phosphate-dehydrogenase the administration of methylene blue is contraindicated, because of worsen of the methemoglobinemia.
The aim of our study was to confirm the diagnosis of partial hydatidiform mole (PMH) and to determine mechanism of PMH development by chromosomal DNA analysis. In our study we analysed 8 cases of morphologically and histologically confirmed PMH. Their karyotype was determined by using methods of direct, 24-hour and a long-term tissue culture. The restriction fragment length polymorphisms (RFLP) method was used for DNA analysis of PMH chorionic villi and from progenitor lymphocytes in peripheral blood. All cases were triploid. DNA analysis revealed in six cases one maternal and two paternal RFLP bands, and in two cases two maternal and one paternal RFLP bands.
PURPOSE: The exact coverage of the lymph nodes and optimal shielding of the organs at risk are necessary for patients with Hodgkin's disease or malignant lymphoma to guarantee a high cure rate and a low rate of late effects for normal tissue. The purpose of this study was to compare conventional simulation and blocking with virtual simulation in terms of coverage of the target volume and shielding of the organs at risk in this highly curative patient group. PATIENTS AND METHODS: In 10 patients diagnosed with Hodgkin's disease and 5 patients with a Non-Hodgkin lymphoma radiation treatment planning for a mantle field or para-aortic field with inclusion of the spleen was performed in a conventional manner and with virtual simulation. With conventional technique, irradiation portals were defined during fluoroscopy and shielding of the organs at risk was drawn onto the simulation films, based on the information from previous X-ray films, CT or MRI scans. For virtual simulation, contouring of the target volumes and organs at risk (e.g. the kidneys) and the definition of the irradiation portals were performed with the AcQSim software package on a VoxelQ workstation (Picker Inc.) This was done in a beam's eye view environment on a currently driven CT scan in the treatment position. Both irradiation portals were compared in terms of coverage of the target volume and shielding of the organs at risk. RESULTS: Planning of a mantle field in the conventional way resulted in an incomplete coverage of the right hilus in 4/15 cases and of the left in 1/15 cases, respectively. The spleen and the spleen hilus were not covered completely in 5/15 and 6/15 cases, respectively. The left kidney was adequately shielded in only two thirds (10/15) of the conventionally planned fields. The planning time required for virtual simulation was reduced for the patient, but was increased for the physician because of the more time consuming contouring procedure compared to conventional simulation. CONCLUSIONS: Virtual simulation based on CT scans for radiation treatment planning of malignant lymphoma gives more information about soft tissue structures than conventional treatment planning. Therefore, it allows a more precise coverage of the target volumes and better shielding of the organs at risk. However, the time required for the whole procedure is increased. This is justified because of the often highly curative intention when treating this group of patients.
AIM: The aim of this study was to determine set-up deviations during irradiation of patients with breast cancer using Electronic Portal Imaging (EPI). PATIENTS AND METHOD: In order to monitor the intrafractional set-up deviations multiple portal image readings were carried out on 5 patients with breast cancer. Moreover interfractional set-up deviations were determined by the acquisition of daily EPIs in a total of 20 patients. RESULTS: The results of intrafractional set-up deviation based on 130 EPIs revealed a maximum lateral and longitudinal (cranio-caudal) deviation of 2 mm (range:-10 mm to 8 mm) as well as 1 degree in rotation (range: -2 degree to 2 degrees). The interfractional set-up deviations in 20 breast cancer patients during a treatment series of 25 fractions showed mean standard deviations of 5 mm in lateral and longitudinal direction, respectively. Only in few cases deviations up to maximally 24 mm were observed. The mean standard deviation of the rotational error was 2 degrees and reached a maximum of 6.5 degrees. CONCLUSION: These results show that intrafractional set-up deviations in breast cancer patients are negligible in clinical practice. They can be attributed to random errors due to patient movement and breathing. The set-up deviations during a treatment series can be differentiated in systematic and random errors. Patient fixation and immobilization is crucial in minimizing random errors. Taking into account 10 mm safety margins as used in our department around the "clinical target volume" (CTV), set-up errors outside of this volume (PTV) were exceptional. The enlarged PTV definition of 15 mm for lateral and cranio-caudal field margins, respectively as used in this study covers 99% of the CTV in all patients.
BACKGROUND: Until today, 25 to 50% of ill or severely disabled patients show qualitative or quantitative nutritional deficits which can lead to a disease aggravation and thus may be a limiting factor in oncologic treatment strategies. Therefore the various options for artificial nutrition should be used according to strict indications. These are whenever the patient is not able to eat (e.g. acute mucositis), does not want to eat (e.g. nausea Grade 3 to 4) or is not allowed to eat (e.g. pancreatitis). METHODS: The principle is to apply as much as possible enteral feeding because of its advantages. Enteral nutrition is more physiological, safer and more reasonable. A prerequisite for an adequate feeding is the optimal nutrient composition and detection of patient's individual nutritional status. Numerous options for the adequate application technique of nutritional support are available: 1. oral diets with commercially available supplement drinks; 2. the pump-assisted application by using nasal or percutaneous probes bears many advantages when some important basic rules are not neglected to guarantee a complication free course, e.g. the choice of right nutrients for the right indications, the control of the tube-position and a smooth build-up of the application; 3. peripheral or central venous application is necessary if contraindications prevent the use of enteral nutrition (e.g. ileus, pancreatitis). The following parameters have to be taken into account when generating a parenteral nutrition programme: diagnosis, the present status of the patient's disease, the actual body weight and ideal weight, the laboratory test results, the need of total energy of nutrients in detail and of fluid and electrolytes. CONCLUSIONS: The prevention of malnutrition by adequate therapies for patients with anorexia or cachexia may contribute to a reduction of morbidity and mortality in cancer therapy. There is also a substantial impact of malnutrition on the outcome of anti cancer therapies. Finally a large decrease in health care costs may result from a prevention of cachexia.
Hyperbaric Oxygenation permits a controlled increase of the partial oxygen pressure in the blood. This technique can be used in cases of tinnitus and sudden deafness when the development in the inner ear and the brain lead to a lack of oxygen and so to a limited energy provision. The results to date allow the recommendation to apply an oxygen high pressure therapy when standard treatments have failed. One can work on an improvement rate of 60-65% with tinnitus. HBO therapy should start as soon as possible. Especially in cases of sudden deafness the success depends on a speedy application of HBO. The HBO therapy broadens the spectrum of treatment possibilities for tinnitus and sudden deafness.