Search

The main purpose of this work is to determine the feasibility and physical characteristics of a new teletherapy device of radiation therapy based on the application of a convergent x-ray beam of energies like those used in radiotherapy providing highly concentrated dose delivery to the target. We have denominated it Convergent Beam Radio Therapy (CBRT). Analytical methods are developed first in order to determine the dosimetry characteristic of an ideal convergent photon beam in a hypothetical water phantom. Then, using the PENELOPE Monte Carlo code, a similar convergent beam that is applied to the water phantom is compared with that of the analytical method. The CBRT device (Converay(®)) is designed to adapt to the head of LINACs. The converging beam photon effect is achieved thanks to the perpendicular impact of LINAC electrons on a large thin spherical cap target where Bremsstrahlung is generated (high-energy x-rays). This way, the electrons impact upon various points of the cap (CBRT condition), aimed at the focal point. With the X radiation (Bremsstrahlung) directed forward, a system of movable collimators emits many beams from the output that make a virtually definitive convergent beam. Other Monte Carlo simulations are performed using realistic conditions. The simulations are performed for a thin target in the shape of a large, thin, spherical cap, with an r radius of around 10-30 cm and a curvature radius of approximately 70 to 100 cm, and a cubed water phantom centered in the focal point of the cap. All the interaction mechanisms of the Bremsstrahlung radiation with the phantom are taken into consideration for different energies and cap thicknesses. Also, the magnitudes of the electric and/or magnetic fields, which are necessary to divert clinical-use electron beams (0.1 to 20 MeV), are determined using electromagnetism equations with relativistic corrections. This way the above-mentioned beam is manipulated and guided for its perpendicular impact upon the spherical cap. The first results that were achieved show in-depth dose peaks, having shapes qualitatively similar to those from hadrontherapy techniques. The obtained results demonstrate that in-depth dose peaks are generated at the focus point or isocenter. These results are consistent with those obtained with Monte Carlo codes. The peak-focus is independent of the energy of the photon beam, though its intensity is not. The realistic results achieved with the Monte Carlo code show that the Bremsstrahlung generated on the thin cap is mainly directed towards the focus point. The aperture angle at each impact point depends primarily on the energy beam, the atomic number Z and the thickness of the target. There is also a poly-collimator coaxial to the cap or ring with many holes, permitting a clean convergent-exit x-ray beam with a dose distribution that is similar to the ideal case. The electric and magnetic fields needed to control the deflection of the electron beams in the CBRT geometry are highly feasible using specially designed electric and/or magnetic devices that, respectively, have voltage and current values that are technically achievable. However, it was found that magnetic devices represent a more suitable option for electron beam control, especially at high energies. The main conclusion is that the development of such a device is feasible. Due to its features, this technology might be considered a powerful new tool for external radiotherapy with photons.

The objective of this study was to compare and analyse the absorbed dose profiles from the conformal radiotherapy planning and experimental dosimetry taken in a breast anthropomorphic and anthropometric phantom. Conformal radiotherapy planning was elaborated in the Treatment Planning System (TPS). EBT2 Gafchromic radiochromic films were applied as dosimeters, positioned internally and superficially in the breast phantom. The standard radiation protocol was applied in the breast phantom. The films were digitalised, and their responses were analysed in RGB. The optical densities were processed, reproducing the spatial dose distribution., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Aim: The goal of this work was to assess the additional dose from secondary neutrons and γ-rays generated during total body irradiation (TBI) using a medical linac X-ray beam., Background: Nuclear reactions that occur in the accelerator construction during emission of high-energy beams in teleradiotherapy are the source of secondary radiation. Induced activity is dependent on the half-lives of the generated radionuclides, whereas neutron flux accompanies the treatment process only., Materials and Methods: The TBI procedure using a 18 MV beam (Clinac 2100) was considered. Lateral and anterior-posterior/posterior-anterior fractions were investigated during delivery of 2 Gy of therapeutic dose. Neutron and photon flux densities were measured using neutron activation analysis (NAA) and semiconductor spectrometry. The secondary dose was estimated applying the fluence-to-dose conversion coefficients., Results: The main contribution to the secondary dose is associated with fast neutrons. The main sources of γ-radiation are the following: (56)Mn in the stainless steel and (187)W of the collimation system as well as positron emitters, activated via (n,γ) and (γ,n) processes, respectively. In addition to 12 Gy of therapeutic dose, the patient could receive 57.43 mSv in the studied conditions, including 4.63 μSv from activated radionuclides., Conclusion: Neutron dose is mainly influenced by the time of beam emission. However, it is moderated by long source-surface distances (SSD) and application of plexiglass plates covering the patient body during treatment. Secondary radiation gives the whole body a dose, which should be taken into consideration especially when one fraction of irradiation does not cover the whole body at once.

Background and Purpose: The purpose of this work was to assess the stability of fiducial markers in the prostate bed and compared their use to surgical clips., Patients and Methods: In this study, 3-4 gold fiducial markers were transrectally implanted in the prostate bed of 14 patients. The stability of the fiducial markers position (fiducial markers fixity) over an EBRT course was assessed. Furthermore, the advantages of the fiducial markers compared to the surgical clips were assessed and the interobserver variation between the two technologies was compared., Results: The mean fiducial marker migration during a course of EBRT was small with 1.2 mm (SD ± 0.8 mm). Compared to fiducial markers, the matches with surgical clips were mismatched ≥ 2 mm in 68% of treatments. This discrepancy of > 2 mm was on average 3.7 ± 1.3 mm. There was less interobserver variability for matching of fiducial markers (0.8 ± 0.7 mm) than for surgical clips (2.0 ± 1.6 mm)., Conclusion: Fiducial markers showed less interobserver variability in matching and less variation in position than surgical clips. Fiducial markers could ultimately help in reducing treatment margins.

Controversy remains about management of the neck in squamous cell carcinoma (SCC) of the maxillary sinus and we know of no reports of the use of elective selective neck dissection for management in this site. We retrospectively reviewed 18 consecutive patients with SCC of the maxillary sinus who were managed by primary operation with curative intent. A total of 13 patients had an elective selective neck dissection, which was invaded in one case 8%. Four patients had regional metastases, two with positive nodal disease confirmed after elective selective neck dissection, and two who developed regional recurrence (both after elective selective neck dissections which were negative (pN0)). A review of other published articles in the English language showed no cases of elective selective neck dissections reported. The mean regional recurrence rate was 12% (range 0-26%) and total mean regional metastases rate 21% (range 5-36%). Elective selective neck dissection did not contribute to an improved rate of neck control with regional recurrence of 11% (2/18) compared with 12% in the review. There is no evidence in this report to indicate that elective selective neck dissections for maxillary sinus SCC will result in better disease control. Future research may indicate fewer radiotherapy fields for necks with pathologically clear nodes after elective selective neck dissection., (Copyright © 2012 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.)

Radiotherapy has been utilized as a treatment for ophthalmologic processes for more than one hundred years. Over this century, the field of ophthalmologic oncology has been revolutionized through medical discoveries, development of novel surgical interventions, and innovation of advanced radiotherapy techniques. In this chapter, novel radiotherapy techniques are considered. Material presented will build on basic radiation therapy principles, techniques, and treatment parameters established in the previous chapter through consideration of intensity modulated radiotherapy, stereotactic radiotherapy, and heavy ion therapy. Deliberation of matters common across advanced radiotherapy techniques including target delineation, treatment planning, and requisites for ensuring accurate, precise treatment delivery will precede discussion of advanced radiotherapy techniques as applied to the management ophthalmologic malignancies., (Copyright © 2013 S. Karger AG, Basel.)

Among primary uveal tumors, uveal melanoma is the most frequently occurring malignant neoplasm, albeit much less common than skin melanoma and indeed most other cancers. Traditionally, uveal melanoma was treated by enucleation of the globe, but is now increasingly been managed by an eye-preserving option, which saves vision without compromising the life of patients. More than 90% of eyes now preserved have some form of radiotherapy; most often episcleral brachytherapy that is easily accessible at many ophthalmic centers. Conversely, teletherapy in the form of charged particle irradiation, stereotactic radiotherapy or radiosurgery is only available at a comparatively small number of centers. Radiotherapy for uveal melanoma causes significant side effects and complications, but the vast majority of patients can keep their eye with some remaining function. This is of significant benefit to the quality of life for many patients. The side effects of radiotherapy are intimately related to the size of the irradiated tumor, hence early detection and identification of tumors that need to be treated is critical to improve the functional outcome. Experience gained from treating uveal melanoma has been expanded to treat benign uveal tumors such as choroidal hemangioma and other malignant tumors such as uveal lymphoma and uveal metastasis., (Copyright © 2013 S. Karger AG, Basel.)

Radiation was first discovered in the late 19th century by Wilhelm Roentgen and has since been used extensively to treat a variety of cancers. Over the last century, we have developed an extensive understanding of the physical properties of radiation as well as radiation biology. Technological advances in the last few decades in medical imaging and radiotherapy delivery have led to the development of highly complex radiation delivery systems such as intensity modulated radiotherapy, which can be utilized to conformally treat complex tumor shapes while minimizing radiation dose to the surrounding normal tissue. To completely appreciate the application of radiotherapy for ophthalmic cancers, it is important to have a basic understanding of radiation therapy. In this chapter, we will discuss the fundamentals of radiation and radioactive decay, the mechanism of tumor cell damage leading to tumor cell apoptosis, as well as radiation and treatment parameters that are relevant for an ophthalmic oncologist. We will also discuss the concept of tissue tolerance which is of critical importance when prescribing radiation treatment as well as introduce the principles of three-dimensional conformal radiotherapy and intensity modulated radiotherapy., (Copyright © 2013 S. Karger AG, Basel.)

Aims and Objectives: To evaluate the Pattern of Oncologic Emergencies seen in Adult cancer patients and the treatment modalities used., Materials and Methods: Between January 2004 and December 2008, a total of 1824 (M:F = 1:1.8) new patients were seen. 196 (M:F = 1:1.4) consecutive patients with histologically confirmed malignancies presenting with or having oncologic emergencies were treated and have been reviewed. Patients' folders were reviewed retrospectively with a structured pro forma. Results were analysed using Epi Info soft ware Version 3.4.1; 2007 Edition., Results: The median age was 49 years and mean age of 42 years (range, 15 - 82 years). M: F = 1:1.4. 162 patients had oncologic emergencies at presentation while 21 during treatments and 13 during follow up. At the time of diagnosis of oncologic emergency, 126 were not on any treatment, 42 patients on hormonal therapy and 28 patients were on diverse chemotherapy. All the patients presented late with 108 patients presenting with metastatic disease and 88 patients with locally advanced disease. Only 35 patients were treated within 1 week of onset of emergency. 59 patients had cervical cancer, 31 patients with breast cancer and 28 patients with prostate cancer. Tumour haemorrhage wass the commonest oncologic emergency seen in 107 patients followed by bone pain with imminent cord compression from bone metastases in 59 patients. Of 107 patients with tumour haemorrhage, 54 patients had cardiovascular collapse with 7 having acute renal failure. Similarly, of the 107 with tumour haemorrhage, 56 patients bled from cervical cancer, 12 patients from breast cancer and 8 patients from urinary bladder. 129 patients were treated with teletherapy, 31 patients had chemotherapy, 27 patients had emergency surgery and 5 patients had chemoradiation. Oncologic emergencies were corrected in 126 patients., Conclusion: Tumour haemorrhage is the commonest oncologic emergency in this environment and teletherapy is the commonest therapy used. More radiotherapy centres are needed for prompt treatment and their usefulness in managing emergencies should be made known. Oncologic emergencies are commonly seen in metastatic and locally advanced disease.

Purpose: The goal of this work was to prepare and to evaluate an off-line adaptive protocol for prostate teleradiotherapy with kilovoltage cone beam computer tomography (CBCT)., Patients and Methods: Ten patients with localized prostate carcinoma treated with external beams underwent image-guided radiotherapy. In total, 162 CBCT images were collected. Position of prostate and pubis symphysis (PS) with respect to the isocenter were measured off-line. Using the CBCT scans obtained in the first three fractions the average position of prostate in relation (AvPosPr) to PB was calculated. On each CBCT scan, the position of prostate with respect to AvPosPr was calculated and cumulative histogram of prostate displacement with respect to AvPosPr was prepared. Using this data, the adaptive protocol was prepared in which (1) based on the CBCT made in the first three fractions the AvPosPr to PS is obtained, (2) in all other fractions two orthogonal images are acquired and if for any direction set-up error exceeds 0.2 cm the patient's position is corrected, and (3) additionally, the patient's position is corrected if the AvPosPr exceeds 0.2 cm in any direction. To evaluate the adaptive protocol for 30 consecutive patients, the CBCT was also made in 10th and 21st fraction., Results: For the first 10 patients, the results revealed that the prostate was displaced in relation to AvPosPr >0.7 cm in the vertical and longitudinal directions only on 4 and 5 images of 162 CBCT images, respectively. For the lateral direction, this displacement was >0.3 cm in one case. For the group of 30 patients, displacement was never >0.7, and 0.3 cm for the vertical and lateral directions. In two cases, displacements were >0.7 cm for the longitudinal direction., Conclusion: Implementation of the proposed adaptive procedure based on the on-line set-up error elimination followed by a reduction of systematic internal error enables reducing the CTV-PTV margin to 0.7, 0.7, and 0.4 cm for the vertical, longitudinal, and lateral directions, respectively.

Purpose: The finite size pencil beam (FSPB) superposition method is a commonly used dose calculation method in intensity modulated radiation therapy (IMRT). The FSPB model assumes that dose for a broad intensity modulated beam can be calculated by superposition of dose from small, pencil-like beams. However, this model is limited to point-like radiation sources and is not valid for finite size sources, such as a Cobalt-60 (Co-60) source of 2 cm diameter. In this paper, the authors present results that show the limitation of this model and propose an alternative model, namely the aperture superposition (AS) model, to calculate photon dose for intensity modulated beams arising from finite size radiation sources., Methods: The AS model is based on adding beam apertures rather than pencil beams. Each aperture is defined as a series of adjacently opened leaves of a multileaf collimator with no closed leaves in between them. The apertures are calculated using the EGSnrc Monte Carlo program. The accuracy of the AS model was tested for dose calculations of fan beams, as encountered in tomotherapy treatment plans. The results were compared with the FSPB model and GafChromic film measurements. The measurements and simulations were performed for a clinical Theratronics T780C Co-60 unit with MIMiC binary multileaf collimator mounted on it., Results: The comparisons between the AS model and film measurements show agreement better than 1.5% in the high dose regions and 3.7% in the low dose regions. On the contrary, film measurement comparisons to the FSPB model show that the FSPB model underestimates the dose by up to 7% for small field sizes such as 2 × 2 cm(2) and 20% for larger field sizes such as 20 × 2 cm(2)., Conclusions: The results presented in this paper indicate that the AS model provides better accuracy than the FSPB model when calculating dose for fan beams from large radiation sources. The implementation of this model to the current treatment planning systems has the scope of advancing Co-60 based IMRT and tomotherapy.

Introduction: To assess the usefulness of circulating IL-16 and RANTES measurements as markers of Graves' orbitopathy (GO) activity and to estimate the role of these cytokines in GO pathogenesis., Material and Methods: 42 individuals were divided into four groups: Group 1 comprised 15 euthyroid patients with clinical symptoms of GO who underwent corticosteroid therapy consisting of intravenous infusions of methylprednisolone (MP) and teleradiotherapy (TR); Group 2 comprised ten patients with hyperthyroid GD (Gtx); Group 3 comprised ten patients with GD in euthyreosis (Geu); and Group 4 comprised seven healthy volunteers age- and sex-matched to Groups 1-3. Serum samples were collected 24 hours before the first dose of MP, 24 hours after the first dose of MP, before TR, and at the end of therapy. Serum IL-16 and RANTES were determined by ELISA and TSH-Rab by RIA., Results: Serum IL-16 levels in patients with GO were significantly elevated at the end of therapy: 346 pg/mL (257-538) compared to IL-16 values before treatment: 250 ng/mL (211-337) and to the control group. RANTES serum concentrations did not significantly differ between studied groups, and immunosuppressive treatment did not influence its level. A negative correlation between TSH-Rab and RANTES was found in all studied groups (R = -0.32, p 〈 0.01)., Conclusions: Our data suggests that IL-16 may exert an immunoregulatory effect in Graves' orbitopathy. Serum measurements of both IL-16 and RANTES may be clinically useful; however, establishing their place in the diagnostics and treatment monitoring of GO needs further research.

Aim: The aim was to obtain inhomogenity correction factors (ICFs) for lung tissue inhomogenity for a Co-60 teletherapy beam using Monte Carlo simulation and to compare them with factors obtained from a commercially available treatment planning system., Materials and Methods: The Monte Carlo simulation code of EGSnrc is used for the depth dose calculations. Two clinical like situations were simulated-dose calculation point beyond the lung tissue volume and dose calculation point within the lung tissue volume. The variation of ICF with lung thicknesses and positions was studied. ICF values were obtained for the similar situations from a commercially available treatment planning system, Theraplan Plus., Results: Percentage depth dose data obtained from Monte Carlo simulation is well matching with the published measurement data. ICFs for lung tissue inhomogenity calculated using the Monte Carlo code are in good agreement with Theraplan Plus TPS values for small inhomogenity thicknesses., Conclusion: These results can be used for the verification of TPS calculation or manual treatment time calculation.

Purpose: Since the 20(th) century, radiotherapy (RT) has been used for treatment of symptomatic splenomegaly (SM). SM occurs in association with hematologic disorders. The purpose of this analysis was to determine the indication, treatment concepts, and efficiency of RT., Material and Methods: Clinical features, treatment concepts, and outcome data during the past 20 years were analyzed. Endpoints were pain relief, symptomatic and hematological response, and treatment-related side effects., Results: From 1989-2009, a total of 122 patients received 246 RT courses because of symptomatic SM. Overall 31 patients had chronic myelogenous leukemia (CML), 37 had chronic lymphocytic leukemia (CLL), 23 had osteomyelofibrosis (OMF), 17 had polycythemia vera (PV), 5 had acute myelogenous leukemia, 4 had idiopathic thrombocytopenic purpura (ITP), 3 had non-Hodgkin lymphoma (NHL), and 2 had multiple myeloma (MM). Patients were treated with (60)Co gamma rays or 5-15MV photons. The fraction size ranged from 10-200 cGy and the total dose per treatment course from 30-1600 cGy. Significant pain relief was achieved for 74.8% of the RT courses given for splenic pain. At least 50% regression was attained for 77% of the RT courses given for SM. 36 patients died within 2 months due to the terminal nature of their disease. Of the RT courses applied for cytopenia, 73.6% achieved a significant improvement of hematological parameters and reduction of transfusion need. Notable hematologic toxicities were reported < EORTC/RTOG II°., Conclusion: The present analysis documents the efficacy of RT. In addition, RT as a palliative treatment option for symptomatic SM should not be forgotten.

Purpose: To quantitatively evaluate the dose distributions of high-dose-rate (HDR) prostate implants regarding target coverage, dose homogeneity, and dose to organs at risk., Material and Methods: Treatment plans of 174 implants were evaluated using cumulative dose-volume histograms (DVHs). The planning was based on transrectal ultrasound (US) imaging, and the prescribed dose (100%) was 10 Gy. The tolerance doses to rectum and urethra were 80% and 120%, respectively. Dose-volume parameters for target (V90, V100, V150, V200, D90, D(min)) and quality indices (DNR [dose nonuniformity ratio], DHI [dose homogeneity index], CI [coverage index], COIN [conformal index]) were calculated. Maximum dose in reference points of rectum (D(r)) and urethra (D(u)), dose to volume of 2 cm(3) of the rectum (D(2ccm)), and 0.1 cm(3) and 1% of the urethra (D(0.1ccm) and D1) were determined. Nonparametric correlation analysis was performed between these parameters., Results: The median number of needles was 16, the mean prostate volume (V(p)) was 27.1 cm(3). The mean V90, V100, V150, and V200 were 99%, 97%, 39%, and 13%, respectively. The mean D90 was 109%, and the D(min) was 87%. The mean doses in rectum and urethra reference points were 75% and 119%, respectively. The mean volumetric doses were D(2ccm) = 49% for the rectum, D(0.1ccm) = 126%, and D1 = 140% for the urethra. The mean DNR was 0.37, while the DHI was 0.60. The mean COIN was 0.66. The Spearman rank order correlation coefficients for volume doses to rectum and urethra were R(D(r),D(2ccm)) = 0.69, R(D(u),D0.(1ccm)) = 0.64, R(D(u),D1) = 0.23., Conclusion: US-based treatment plans for HDR prostate implants based on the real positions of catheters provided acceptable dose distributions. In the majority of the cases, the doses to urethra and rectum were kept below the defined tolerance levels. For rectum, the dose in reference points correlated well with dose-volume parameters. For urethra dose characterization, the use of D1 volumetric parameter is recommended.

Background & Objective: Cisplatin-based concurrent chemoradiotherapy has become the standard treatment modality for locally advanced cervical cancer. However, the optimal chemotherapy regimen combined with radiotherapy remains controversial. This study was to compare the therapeutic efficacy and toxicity of concurrent chemoradiotherapy with those of radiotherapy, and those among different regimens of concurrent chemoradiotherapy for stage IIB-IIIB cervical cancer., Methods: From Jan. 2003 to Dec. 2004, 285 patients with stage IIB-IIIB cervical cancer treated in Maternal and Child Health Hospital of Jiangxi Province were randomly assigned to receive radiotherapy alone or concurrent chemoradiotherapy. According to different chemotherapy regimens, patients in the concurrent chemoradiotheapy group were randomly chosen to receive radiotherapy with chemotherapy of bleomycin and cisplatin (RT+BP), radiotherapy with chemotherapy of taxol and carboplatin (RT+TP), and radiotherapy with chemotherapy of 5-fluorouracil and cisplatin (RT+FP). The 3-year survival rates and toxicity of different groups were compared., Results: After a median follow-up of 42 months, the 3-year survival was higher in the concurrent chemoradiotheray group (75%) than in the radiotherapy group (65%) (P=0.042). Acute treatment-related toxicity (grade III and IV) was higher in the concurrent chemoradiotherapy group than in the radiotherapy group (P<0.001); while the delayed treatment-related toxicity was similar in the two groups (P=0.613). The 3-year survival rates of BP, TP and FP chemoradiotherapy groups were 74%, 80% and 71%, without significant differences (P=0.792). Acute toxicities (grade III and IV) and delayed toxicities were similar among the three groups., Conclusions: Concurrent chemoradiotherapy significantly improves the survival for patients with stage IIB-IIIB cervical cancer compared to radiotherapy alone. Among the three chemoradiotherapy regimens, radiotherapy combined with taxol and carboplatin exerts a slightly higher 3-year survival than the other two regimens with tolerable toxicity.

Authors discuss laryngeal lesions, metastases, and relevant anatomy. Outcome of surgical and radiotherapy in terms of voice preservation is discussed. Radiation techniques and outcomes for laryngeal cancer are presented along with discussion of interdisciplinary treatment. Authors review studies and quality of life outcomes of surviving laryngeal cancer patients.

Objective: This phase I clinical trial for cervical carcinoma had three objectives: to evaluate the toxicity of a concurrent chemoradiation regimen featuring weekly nedaplatin; to determine the recommended dose of nedaplatin for a phase II concurrent chemoradiation trial; and to evaluate the formula for predicting area under the curve data for nedaplatin through pharmacokinetic studies., Patients and Methods: Twelve patients with locally advanced squamous cell carcinoma of the uterine cervix were enrolled. Nedaplatin was administered once a week for 6 weeks. The starting dose of nedaplatin was 25 mg/m(2)/week, with increments of 5 mg/m(2)/week planned for each dose level. Three cases were enrolled at each of the dose levels. Radiation therapy was delivered with both external beam teletherapy and intracavitary brachytherapy with HDR-RALS. Volunteering patients underwent pharmacokinetics studies during the second course., Results: Nedaplatin at a dose of 25, 30, and 35 mg/m(2) was safely administered for three cases at each dose level. At a dose of 40 mg/m(2), however, all three cases had Grade 3 neutropenia. Observed area under the curve value and predicted value was closely correlated, with differences between the two area under the curve values within 25%. All 12 cases achieved a clinical complete response, as evaluated with RECIST., Conclusions: Our recommended dose for a phase II trial of concurrent chemoradiation with weekly nedaplatin is 35 mg/m(2). The formula can predict unbound concentration of nedaplatin based on area under the curve within 25% error.

The optimal management of clinically localized (T1, T2) prostate cancer remains controversial. Patients have possibility of choice between prostatectomy and radiotherapy in two forms: external beam radiotherapy and brachytherapy. Multicentre studies show comparable results of theise two methods. The aim of this paper is to present current knowledge regarding treatment with conformal radiotherapy. Acute and late effects of ionizing radiation are described. Propriety of associate radiotherapy with hormonotherapy was analyzsed.

Background: Low dose radiotherapy is commonly used for painful rheumatic conditions in clinical practice. Teleradiotherapy may be a cheap, painless procedure which is applicable to many joints at a time., Objective: To determine if the local application of x rays to inflamed joints in rheumatoid arthritis (RA) affects the signs and symptoms of inflammation., Methods: In a randomised, controlled, double blind study, roentgen irradiation was administered in a total dose of 20 Gy during 2 weeks to single joints in six patients with RA who were receiving constant and stable pharmacological treatment with DMARDs and NSAIDs. Single inflamed joints on the contralateral side of the body were used as controls and received sham irradiation. Swelling and tenderness was assessed by blinded investigators before and until 3 months after the irradiation; general disease activity and pain scales were included in the assessment., Results: No change in the scores for tenderness, swelling, pain, or disease activity was seen. The trial was stopped for ethical reasons., Conclusion: Local roentgen treatment of RA at a substantial dose of 20 Gy was ineffective in this pilot trial.

Purpose: The purpose of this investigation was to evaluate the quality of life, measured in LENT-SOMA and DISCHE scale, of patients with xerostomia as late irradiation injury., Materials and Methods: 45 head and neck cancer patients were radically irradiated receiving doses from 48 Gy to 76.8 Gy (mean: 65.1 Gy) on PTV. Patients received doses from 48 to 76 Gy on salivary gland (mean: 63.8 Gy, SD: 8). The irradiation injury of the oral cavity was assessed using DISCHE scale at the end of radiotherapy and late radiation sequels of salivary gland was assessed in 6 and 7 month after radiotherapy using DISCHE and LENT-SOMA scale. The average follow-up for this group of patients was 8 months., Results: All patients with 6 and more points of acute reactions assessed in DISCHE scale at the end of radiotherapy have had xerostomia in follow-up period. Results measured by LENT-SOMA scale was similar to DISCHE scale., Conclusions: Dose escalation of radiotherapy increases number of xerostomia as late irradiation injury. Both scales (LENT-SOMA and DISCHE) are similar in qualifying and quantifying of salivary gland radiation injury. Minimal therapeutic dosage prescribed on salivary gland after which irradiation injury occurred was 63 Gy.

The purpose of this study was to develop an easily accessible technique for the delivery of postoperative radiotherapy for the treatment of earlobe keloids. Forty-seven earlobe keloids were given postoperative radiation using the smallest achievable half field Telecobalt technique. Results showed 41 (87.2%) of treated patients' postoperative scars remained free from recurrent keloid formation. Acute reactions were minimal and patient compliance was excellent. In conclusion, the technique described in this study for the delivery of postoperative radiation to earlobe keloids should be readily available in areas of high prevalence. Results are comparable to previously used radiotherapy techniques.

Purpose: To examine the feasibility and reliability of insertion of internal fiducial markers into various organs for precise setup and real-time tumor tracking in radiotherapy (RT)., Materials and Methods: Equipment and techniques for the insertion of 2.0-mm-diameter gold markers into or near the tumor were developed for spinal/paraspinal lesions, prostate tumors, and liver and lung tumors. Three markers were used to adjust the center of the mass of the target volume to the planned position in spinal/paraspinal lesions and prostate tumors (the three-marker method). The feasibility of the marker insertion and the stability of the position of markers were tested using stopping rules in the clinical protocol (i.e., the procedure was abandoned if 2 of 3 or 3 of 6 patients experienced marker dropping or migration). After the evaluation of the feasibility, the stability of the marker positions was monitored in those patients who entered the dose-escalation study., Results: Each of the following was shown to be feasible: bronchoscopic insertion for the peripheral lung; image-guided transcutaneous insertion for the liver; cystoscopic and image-guided percutaneous insertion for the prostate; and surgical implantation for spinal/paraspinal lesions. Transcutaneous insertion of markers for spinal/paraspinal lesions and bronchoscopic insertion for central lung lesions were abandoned. Overall, marker implantation was successful and was used for real-time tumor tracking in RT in 90 (90%) of 100 lesions. No serious complications related to the marker insertion were noted for any of the 100 lesions. Using three markers surgically implanted into the vertebral bone, the mean +/- standard deviation in distance among the three markers was within 0.2 +/- 0.6 mm (range -1.4 to 0.8) through the treatment period of 30 days. The distance between the three markers gradually decreased during RT in five of six prostate cancers, consistent with a mean rate of volume regression of 9.3% (range 0.015-13%) in 10 days., Conclusions: Internal 2.0-mm-diameter gold markers can be safely inserted into various organs for real-time tumor tracking in RT using the prescribed equipment and techniques. The three-marker method has been shown to be a useful technique for precise setup for spinal/paraspinal lesions and prostate tumors.

Chang-hua Christian Hospital needs to uninstall the 60Co unit. The mode of this 60Co teletherapy unit is SHIMADZU RTGS-10. The original lead head was taken as the source container of this 60Co unit. The source head was dismantled and put into the prepared wooden box, after the source was sealed. This study describes the planning and dismantling of the retirement and transport of the 60Co unit, and personal doses measured during the procedure. This work estimates the doses of radiation received by exposed workers during the dismantling of the machine. The workers received doses of approximately 53 microSv. This study shows that the original lead head can be used as the source container of this 60Co unit. The 60Co machine was smoothly dismantled and transported by conscientious and careful workers, using planned and controlled radiation protection, following the ALARA (as low as reasonably achievable) rule.

In photon teletherapy, the size and functional form of the photon source spot affect both the sharpness of the penumbra of treatment fields and the sharpness of portal images. Photon source spot parameters are also used in photon teletherapy dose calculation codes. A simple method for characterizing the source spot would complement the existing, more involved methods that have been described in the medical physics literature. Such a method, using a rollbar made of tungsten or other high-Z metal, is used in industrial radiography. We describe the use of a tungsten rollbar for characterizing the source spot edge spread function (and thereby the source spot size and shape) of a megavoltage bremsstrahlung photon source. We use Monte Carlo simulations to quantify anticipated experimental artifacts of the method, assuming typical spot sizes for circ-function, Gaussian, and Bennett line shapes. We illustrate the use of the rollbar method by characterizing the source spot of a typical 9 MV linac used for industrial radiography. The source spot is analyzed using two approaches: (a) fitting the rollbar image with analytic functions and (b) using Abel inversion to obtain the cylindrically symmetric spot profile consistent with the measured rollbar image. Monte Carlo simulations, based on a 6 MV photon teletherapy accelerator, suggest that aspects of the method are applicable to medical bremsstrahlung sources.

The doses over various parts of the body of 7 patients with cancers of the pharynx, breast and cervix during radiotherapy treatment with a megavoltage 60Co therapy machine were measured using LiF TL dosemeters. The doses on the surface of the patients outside the primary beam were found to vary with a maximum of 366 mGy at the abdomen of a cervix cancer patient to a minimum value of 1.1 mGy at the left arm and left leg of a pharynx cancer patient. The observed variations in the doses were attributed to the difference in patients' tumour location, exposure and anatomy. In the treatment of pregnant women and women of childbearing age, the results presented will be a good starting point for estimation of fetus doses and doses to organs outside the planning region.

Background: Radiotherapy is accepted as standard adjuvant treatment for low-stage seminoma and results in excellent survival rates. The optimal radiation field for stage I seminoma, however, is still being discussed., Patients and Methods: In a retrospective study we evaluated long-term results concerning survival, relapse-pattern, and acute and chronic toxicity in patients receiving adjuvant radiotherapy of the paraaortic and ipsilateral iliac lymph nodes (hockey-stick, HS) versus radiotherapy of the paraaortic lymph nodes only (PA). From 1979-1997, 129 patients (median age 32 years) in clinical stage I received adjuvant radiotherapy. Eighty-seven patients were treated with 36 Gy to the HS field and 42 patients were treated with a median of 28 Gy to the PA field., Results: With a median follow-up of 7.7 years (HS) and 5.2 years (PA) the relapse rate was 3.4% and 2.4%, respectively. There was no abdominal or pelvic recurrence in either group. Radiotherapy was well tolerated in both groups. No significant difference in acute or chronic toxicity was noted. However, lower gastrointestinal tract toxicities and myelotoxicities appeared less frequent in the PA group. Second malignancies only occurred in the HS group. Overall survival in the HS and PA group was 96.6% and 100%, respectively. No patient died of seminoma., Conclusion: With paraaortic radiotherapy only, long-term disease-specific survival was excellent. Decreased risk of acute toxicity and of second malignancies are potential benefits of the reduced radiation field.

A prospective phase II trial was initiated in previously untreated patients with locally advanced nasopharyngeal carcinoma (NPC). The goal was to achieve improvement in locoregional control, disease-free interval and overall survival using induction chemotherapy and to compare conventional fractionation (CF) with an accelerated hyperfractionation (AHF) regimen. Fifty patients were treated (5 AJCC Stage III, 45 Stage IV) with induction chemotherapy consisting of two cycles of cisplatin and 5-fluorouracil. Patients were then randomized between CF and AHF therapy. A clinical response to induction chemotherapy was reported in 86% of patients prior to radiotherapy (44% complete response, 42% partial response). Patients with complete or major partial responses to induction chemotherapy had a significantly better 5-year overall survival (60%) and disease-free interval (59%) than those with no response or minor partial response (15% and 18% p = 0.009 and 0.0009). Acute radiation reactions were more pronounced in the AHF group (p = 0.0002), and the incidence of late normal tissue injury was more frequent (p = 0.08). At 5 years, the locoregional control rate was higher in the AHF arm (76%) than in the CF group (54%), but the difference was not significant (HR, 0.52; 95%, Cl, 0.15-2.83; p = 0.186). With a median follow-up period of 55 months (range 4-120), the 5-year disease-free interval and overall survival rates were more favorable in the AHF group than in the CF group, but the differences were not significant (59% and 54% vs. 34% and 36%, respectively, HR for disease-free interval = 0.71; 95% CI, 0.27-1.88; p=0.198 and HR for overall survival = 0.81; 95% CI, 0.37-1.78; p=0.433). The overall treatment failure rate was 48%. Locoregional failures occurred in 12 patients (24%) and the incidence of distant metastases reached 30%. Response to induction chemotherapy is strongly predictive for locoregional control, disease-free interval and overall survival. Accelerated hyperfractionation was associated with high incidence of acute and late toxicity without significant improvement in locoregional control rate. The optimal chemotherapy dose and sequencing with radiotherapy needs to be investigated in future studies. Distant metastases remain the main cause of treatment failure in NPC.

The paper presents seven cases of central nervous system lymphomas diagnosed in Department of Neurosurgery of Military Clinical Hospital in Bydgoszcz. The role of stereotactic biopsy in the management of this entity is underlined. Clinical, radiological and pathological symptoms met in PCNSL (Primary Central Nervous System Lymphoma) are briefly described.

The role of teleradiotherapy in the treatment of patients with thyroid cancer is presented. The indications for external irradiation include patients with: primary inoperable disease or inoperable recurrence, microscopic or gross residual disease after surgery, high risk of local regional failure, and metastatic thyroid cancer, especially with skeletal, brain and mediastinal metastases.

The absorbed dose water in a Co-60 teletherapy beam has been measured with four different standard ionisation chambers applying two codes of practice and also, with a Fricke dosimeter. Measured values agree generally within 2.3%. There is a remarkable agreement of less than 0.3% variation, between ionisation chambers NE 2561 and NE 2481 when the IAEA protocol is applied. The HPA protocol is applicable to only NE 2561 and a variation of about 1.4% was observed between measurements made with this ionisation chamber applying the two protocols. The IAEA protocol shows very accurate results. With a deviation of about 2.2%, the Frickle dosimeter appears to be the least accurate for therapy dose measurement despite its simplicity of application.

Objective: To investigate the effect of radiotherapy dose on penetration of 5-FU (5-fluorouracil) in blood-pancreatic barrier in rats., Methods: After the pancreatic region of the rats were irradiated by 2, 10, 20, 30 and 40 (Gy) doses of gamma-ray, we investigated the penetration ratio (PR) of 5-FU in the pancreatic tissue with HPLC assay., Results: When treated with low-dose of gamma-ray (2 Gy), the PR of 5-FU increased obviously after 8 hours. But in the high-dose groups (>/= 10 Gy), the PR was less than or had no difference with control group. At the same time, we found that the islets had appeared pathological degeneration, while the pancreatic lobular structure, acini and ducts had no visible changes in 20 Gy group., Conclusions: After the treatment of low-dose of gamma-ray combined with 5-FU, the effect of chemoradiotherapy may be improved for enhanced PR of 5-FU in pancreatic tissue, and at the same time, chemotherapy and radiotherapy cooperate with each other. But in high dose groups (>/= 10 Gy), radiotherapy may reduce the effect of chemotherapy in acute phase. After high-dose radiotherapy, we should pay attention to the change of glucose-resistance of patient to reduce the incidence of radiotherapy complication.

Aim: Differential radiomodification induced by 2-deoxy-D-glucose (2-DG) is proving to be a feasible modality for optimizing tumor radiotherapy. Our earlier work on Ehrlich ascites tumor cells has shown that pretreatment with hematoporphyrin derivatives increases the uptake and phosphorylation of 2-DG. Moreover, the alteration induced in bioenergetic profile was more drastic and less reversible. The promising combination of hematoporphyrin derivatives and 2-DG has been further evaluated in the Ehrlich ascites tumor bearing mice for determining the effects on radiotherapeutic response., Materials and Methods: Solid tumors (average volume = 0.9 +/- 0.1 cm3) implanted in Swiss-albino strain "A" mice were focally irradiated (10 Gy) using 60Co teletherapy. Drugs were administered intravenously. Tumor bioenergetics was assessed by 31P MR spectroscopy., Results: The uptake and phosphorylation of 2-DG was observed to be increased following pretreatment with hematoporphyrin derivatives. Upon hematoporphyrin derivatives + 2-DG treatment followed by irradiation, the intracellular pH reduced and a remarkable increase in glycerophosphorylcholine and inorganic phosphate levels was observed., Conclusion: The present study demonstrates the potential of hematoporphyrin derivative pretreatment in increasing the bioavailability of 2-DG in a mice Ehrlich ascites tumor model. The finding may have interesting clinical implications in the form of increased manifestation of the radiation-induced damage in the case of use of these drugs as a potential adjuvant in radiotherapy of tumors.

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.

Purpose: Numerous clinical observations demonstrate the efficacy of low radiation doses in the treatment of painful osteoarthritis. Experimental investigations remain scarce. We investigated the effects of locally daily 5 times 1.0 Gy 60-Co irradiation on an artificially induced aseptic gonarthritis in rabbits., Material and Methods: Three separate experiments (EV) were performed (10 rabbits per experiment, 5 treated/5 controls; duration: EV1: 18 days; EV2: 6 days; EV3: 29 days). An aseptic arthritis in the right knee joint of rabbits was induced by intraarticular injection of 0.5 ml papain solution (3%, 30,000 USP/mg) on day 0. The arthritic knee joint of the anesthesized animals was irradiated daily from day 1 to 5 with 5 times 1.0 Gy. The controls were sham-irradiated under the same conditions. The time course of arthritis in treated animals and sham-treated controls was evaluated by clinical, laboratory-chemical and histological criteria. The clinical investigation was performed daily, the puncture of the knee-joints was carried out several times in EV1, and at the end of experiments in EV2 and EV3. At the end of the observation period, animals were killed and the knee joints excised for histological analysis., Results: The intraarticular injection of papain caused a peracute inflammatory response in all animals. After 1 week the chronic stage was reached, and the experimental arthritis resolved slowly within several weeks. Local irradiation accelerated the decrease of inflammatory joint swelling, being significant by day 4. On day 6 the volume of synovial fluid in irradiated knee-joints was significantly smaller. The morphometric data indicated a reduction in thickness of synovial membrane, a decrease in number of synovial cell layers, and a decrease in distance between capillaries and the synovial membrane surface following irradiation of arthritic joints. Due to considerable individual variability, the morphometric data partially did not reach statistically significance., Conclusion: The experiments provide evidence for an antiphlogistic effect of irradiation with 5 times 1.0 Gy in vivo. They support the clinical observations of the efficacy of anti-inflammatory radiotherapy.

Background: Soft tissue sarcomas are relatively rare tumors with an aggressive natural history associated with a high propensity for local recurrence following conservative surgery. It accounts for 1.8% of all cancers seen at the Tata Memorial Hospital, Mumbai. Organ preserving surgery and tumor bed brachytherapy have revolutionized the management of soft tissue sarcomas., Patients and Methods: One hundred and seventy-seven patients with histologically proven non-metastatic cases of soft tissue sarcomas in the age group of 16 to 79 years (median 41 years) were treated at the Tata Memorial Hospital between January 1983 and December 1992. One hundred and fifty-one patients who had completed a minimum of 24 months of treatment were studied. There were 100 males (66%) and 51 females (33%). The majority had recurrent lesions (70.3%). Extremities were involved in 75% of patients. Spindle cell sarcoma was the major histologic variant (30%). The patients underwent function preserving surgery and temporary afterloading Ir-192 tumor bed brachytherapy with or without external radiotherapy., Results: In patients receiving brachytherapy only, 25 out of 33 (75%) were locally controlled after a median follow-up of 30 months. After successful salvage of local failures the overall local control improved to 82%. Similarly in the patients who received both interstitial brachytherapy and external irradiation, the local control rate after a median follow-up of 40 months was 71% which improved to 86% after successful salvage. The overall treatment related complication rate was less than 1%. The only marginally significant prognostic factor for local control was tumor grade (p = 0.06)., Conclusions: The sequential combination of limited surgery and tumor bed brachytherapy with or without external radiotherapy has been established as an effective alternative to more ablative procedures like amputation. Histologic grade has proven to be a significant factor determining local control.

Background: In order to evaluate whether individualized technique and dosimetry of radiotherapy increase local control, organ preservation, and survival of patients with T1 glottic cancer, we reviewed 76 cases treated from 1979 to 1993., Methods: Group A included 32 patients treated from 1979 to 1989 with different techniques, based on clinical aspects. Group B included 44 patients treated from 1990 to 1993 with individualized technique according to tumor extension and patient's anatomy., Results: Five-year local control with radiotherapy alone was achieved in 53% of group A versus 91% of group B (P > 0.005). Survival was similar in both groups with rescue surgery (90% versus 96%). Five-year survival with larynx preservation was 65% in group A versus 88% in group B (P = 0.02). Most recurrences (78%) appeared within 24 months of follow-up., Conclusion: Adequate staging, individualized technique, computing planning using simulation and use of immobilization devices during cobalt-60 radiotherapy significantly increase local control and organ preservation in T1 glottic cancer.

Aim: This work is engaged with the volume change of neck lymph node metastasis of malignant tumors in the head-neck region during radiotherapy., Patients and Method: In 54 patients with head and neck tumors, the volume of neck lymph nodes before and after radiation was measured. The volumetry was done with CT planimetry. The total dose was 66 Gy (2 Gy/d) telecobalt from 2 lateral opponated fields. The time of volume change could be defined with measuring of the half-time and the doubling-time by the help of Schwartz formula., Results: After 10 Gy the volume diminution was about 20% and half-time 24 to 26 days. Afterwards the time of volume diminution picked up speed and finally achieved 60 to 72%. Meanwhile the half-time decreased to the half value. The result was independent of the site of primary tumor, the patient's sex and age., Conclusion: In our opinion the effectivity of radiotherapy can best be judged with defining of the volume change of lymph nodes of the neck.

Objective: To find a more effective treatment of primary hepatocellular carcinoma by using combined therapy of Chinese herbal medicine with radiotherapy., Methods: Prospective study was conducted with double-blind method on prognosis of patients treated with combined therapy of Xuefu Zhuyu decoction and move stripe field radiation on entire liver. A control group was established and treated with placebo and radiotherapy., Results: The 1-, 3- and 5-year survival rates of the test group were higher than those of the control group by 20.0%, 23.4% and 16.6% respectively. The remote metastatic rate of the two groups were not different significantly., Conclusions: Xuefu Zhuyu decoction showed coordinative effect with radiotherapy on antitumor, it could enhance the radiosensitivity of liver cancer cells, increase the radiation tolerance of normal hepatocytes and reduce the side effect of radiotherapy.

Aim: Factors which influence the accuracy of the field application during daily irradiation routine are not well known. The aim of this prospective analysis was to determine the significance of these factors on the occurrence of field misadjustments in irradiation without immobilization and to evaluate their clinical relevance., Patients and Methods: Fifty-three patients received external cobalt-60 beam irradiation without fixation. Once weekly portal images of all treatment fields were carried out. In addition to objective patient data (age, weight, height, general condition, irradiation indication), the psychological situation of the patient during treatment (anxiety, restlessness, pain) and work circumstances of the medical staff during treatment were evaluated once weekly. The distance of clearly visible anatomic structures to the field borders of the portal images were measured and the deviation to the corresponding simulator images was calculated. Patient data were correlated to the number of field misadjustments (deviation larger than 1 cm)., Results: Patients whose condition is generally poor and patients being treated palliatively, patients with feeling of anxiety, restlessness or pain during simulation or irradiation and heavy patients (90 kg and more) were more often misadjusted. The number of field misadjustments increased with the stress of the medical staff., Conclusions: The problem of reproducibility of external beam irradiation without fixation in palliative treatment is of clinical relevance. Effective analgesic therapy and a comfortable and painfree patient set-up reduce misadjustments. In curative treatment, immobilization techniques should be used.

Background: Cancer of the vagina is the least frequent primary malignant tumor of the female genital tract except carcinoma of the fallopian tube. Radiation therapy is the preferred treatment in most cases., Patients and Method: Between 1965 and 1991, 39 patients (median age 66 years) with primary carcinoma of the vagina were treated with radiation therapy at our clinic. The mean observation period was 37 months. Classification according to the FIGO yielded a stage I in 43%, stage II in 24%, stage III in 22% and stage IV in 11%. Histological differentiation resulted in 35 squamous cell carcinomas and 4 adenocarcinomas. In 69%, the tumor was found on the posterior or lateral wall of the vagina, in 43% it arose from the upper third of the vagina. Standard therapy consisted of combined brachy- and teletherapy. Most of the brachytherapy applications were performed with a radium source., Results: Median survival was 37 months, calculated according to the Kaplan-Meier method. The 5-year actuarial survival rate for all stages was 41% (stage 1: 62%, stage II: 44%, stage III: 25%). Sixty-eight percent of all patients achieved a complete remission, 19% a partial response. Significant prognostic factors were stage of disease and histological grading., Conclusion: Our results demonstrate the value of radiation therapy for the treatment of primary carcinoma of the vagina. Combined treatment with both external beam radiation and brachytherapy should be preferred.

Purpose: Complex 3D treatment planning techniques require a dose verification throughout the irradiated volume. Conventional dosimetry techniques only unsatisfyingly serve these needs., Material and Method: The chemical dosimeter FeSO4 solution can be used for measuring spatial dose distributions with the help of magnetic resonance imaging by fixing the iron ions in a gelatin matrix. A 3D dosimetry method was developed for 3D verification in an homogeneous, anthropomorphic phantom. The verification is achieved by juxtaposition or superposition of measured and calculated isodoses., Results: Different gel compositions were studied in view of their applicability as clinical 3D dosimeter concerning dose response, linearity and diffusion behaviour. A gel with 5% gelatin and 1 mM of ferrous ions proved to be the most suitable. The inverse spin-spin relaxation time T2(-1) is an indicator of the ferric ion concentration that showed to be linear with the dose in the range between 0 and 40 Gy (R2 = 0.996). The dose response was 0.057 per second and Gy. The observed diffusion of the iron ions was only influenced little by different gel compositions. To isolate the restrictions in the clinical application, measurements on the disturbing effects like, e.g. the inhomogeneous spatial response and the gel surface effects, were made and eliminated with the subtraction method. The clinical use of the method is demonstrated for the examples of the verification of calculated 3D dose distributions of a shielded 192Ir afterloading vaginal applicator and a head and neck 3-field plan with the use of asymmetric jaws and compensators., Conclusion: The study demonstrates the clinical applicability of the method and shows its limitations.