Radiotherapy instead of axillary lymph node dissection: evaluation of axillary lymph node dose coverage with whole breast radiotherapy.

Background: The purpose of this study was to investigate the dose coverage of sentinel lymph nodes (SLN), level I, II and III axillary volumes from tangent fields for breast cancer patients with positive SLN without axillary dissection. Materials and methods: In 30 patients with cN0 invasive breast cancer treated with breast conserving surgery and SLN biopsy, the SLN area was intraoperatively marked with a titanium clip. Retrospectively, the SLN area and axillary target volumes were contoured, and three plans [standard tangent fields (STgF), high tangent fields (HTgF), and STgF + axillary-supraclavicular field] were generated for each patient. The prescribed dose was standardized to 50 Gy in 2 Gy fractions to the isocenter. Results: The mean dose with STgF or HTgF was 33.1 and 49.1 Gy (p = 0.0001) in the SLN area, 25.7 and 45.1 Gy (p < 0.0001) in the volume of level I, 7.2 and 28.9 Gy (p < 0.0001) in the level II and 3.5 and 12.7 Gy (p = 0.0003) in the level III. Adequate therapeutic doses to the level II or III volumes were delivered only with STgF + axillary-supraclavicular field. The mean dose of ipsilateral lung was the highest with the three-field-technique, 9.9 Gy. SLN area, level I, II or III were completely included in the HTgF with 93.3%, 73.3%, 13.3% and 0%, respectively. Conclusions: SLN area should be marked by surgical clip and axillary target volumes should be contoured to obtain accurate dose estimations. The use of HTgF improve axillary coverage.

Comparison of three film analysis softwares using EBT2 and EBT3 films in radiotherapy.

Introduction The purpose of the study was to compare the results of gamma value based film analysis according to the used type of self-developer film and software product. Material and methods The films were irradiated with different treatment techniques such as 3D conformal and intensity modulated radiotherapy with static and rotational delivery. Stereotactic plans with conformal and intensity modulated arc techniques, using coplanar and non-coplanar beam setup were also evaluated. The data of irradiated film were compared with the planned planar dose distribution exported from the treatment planning system. Three film analysis software programs were evaluated: PTW Mephysto (PTW), FilmQA Pro (FQP) and radiohromic.com(RC). Both EBT2 and EBT3 types of films were examined. The comparisons of dose distributions were performed with gamma analysis using 10% cut-off level. Results The results of the gamma analysis for larger fields were between 78.3% and 98.3%, 75.7% and 100%, 80.2% and 98.8% with PTW, FQP and RC, respectively. The results of evaluation in case of stereotactic measurements were 76.8%-99.2% for PTW, 95.7%-100% for FQP and 91.2%-99.9% for RC. Conclusions All the three software programs are suitable for calibrating and evaluating films, performing gamma analysis, and can be used for patient specific quality assurance measurements. There is no direct connection between gamma passing rate and absolute accuracy or software quality, it is just a feature of the software. The interpretation of own results has to be defined on an institutional level according to given workflow and preliminary results.

[Dose coverage of axillary target volumes using different field arrangements following breast conserving surgery for invasive breast cancer]. / Az axilláris nyirokcsomók dózisa különféle besugárzási mezõelrendezésekbõl emlõmegtartó mûtét után.

The purpose of this study was to investigate the dose coverage of sentinel lymph node (SLN) site, level I, II and III axillary target volumes using different field arrangements (standard or high tangent fields: STgF, HTgF and STgF + axillary-supraclavicular field: ASF) in N0 invasive breast cancer patients treated with breast conserving surgery. In 30 patients the SLN site was marked with titanium clip. They were treated with 3D-conformal radiotherapy. Retrospectively, for the purpose of this study, the SLN site and axillary target volumes were contoured, and three plans were generated for each patient using the original CT data. The prescribed dose was 50 Gy (2 Gy/fraction). The mean dose with STgF or HTgF was 33.1 and 49.1 Gy (p=0.0001) in the SLN site, 25.7 and 45.1 Gy (p<0.0001) in level I, 7.2 and 28.9 Gy (p<0.0001) in level II and 3.5 and 12.7 Gy (p=0.0003) in level III. The mean dose with STgF+ASF in level II or III was 45 and 46 Gy. The dose coverage is inadequate to all axillary levels with STgM. The target volumes should be delineated to give accurate dose estimation.

[Stereotactic body radiotherapy of liver metastasis: early experience]. / Májáttétes betegek sztereotaxiás ablatív sugárkezelésével (SABRT) elért elsõ eredményeink.

Recently the prevalence of oligometastatic patients is increasing. A common site of distant spread is the liver. The standard of care is curative surgical resection, however, the resecability rate is only 10-20%. Alternatively, radiofrequency ablation (RFA) or transarterial chemoembolization (TACE) may be used. Stereotactic ablative body radiotherapy (SABRT) makes it possible to deliver curative radiation dose without radiation injury to the healthy liver tissue. We delivered SABRT to three patients with inoperable hepatic metastases. The primary tumors were rectal (2) and lung (1). The dose was 3x20 Gy every other day. We observed one grade 1 side effect. All the metastases showed complete remission and no local recurrence or late side effect occurred during the one year of follow-up. One patient is tumor-free, one has stable disease, in one patient two new hepatic metastases appeared and receives chemo-biological therapy. SABRT of liver metastases is safe and highly effective. It can be expected that in the near future it will become one of the standard treatments of hepatic tumors.

[Stereotactic ablative body radiotherapy (SABRT) for locally advanced pancreatic cancer. Case report and review of literature]. / Lokálisan kiterjedt hasnyálmirigy-daganatos beteg sztereotaxiás ablatív sugárkezelése (SABRT): esetismertetés és irodalmi áttekintés.

Pancreatic cancer has one of the worst outcomes among malignant tumors. At the time of diagnosis only 20% of the cases are resectable and 30-50% are locally advanced, when curative intervention cannot be performed. After resection local relapse occurs in 20-60%, and in 30% it is the reason of death. This latter highlights the importance of local control. However, there have been no convincing results with conformal radiation therapy and radiochemotherapy yet. Adjuvant radiochemotherapy has been settled into the routine in the US, but not in Europe and Asia and only sporadic data are available about neoadjuvant radiotherapy. Based on the result of recent studies, conformal radiation therapy does not seem to become part of the standard treatment of locally advanced disease. Radiation resistance, long treatment time and incompatibility with the most advanced chemotherapy regimens may make conformal radiotherapy ineffective. Stereotactic ablative body radiotherapy (SABRT) when a limited target volume is irradiated in few fractions, with high precision and high biological effective dose, is ablative for the tumor and could be a possible solution for this issue. In our report, we describe to our knowledge the first SABRT for locally advanced pancreatic cancer in Hungary and give a short literature review.

[Investigating the clinical applicability of EBT2 self-developing films]. / Az EBT2 önhívó filmek sugárterápiás klinikai alkalmazhatóságának vizsgálata.

The purpose of the study was to investigate the physical properties of the EBT2 radiochromic films and define the conditions of its clinical applicability. We irradiated the films with different treatment techniques 3D conformal (3DCRT), intensity-modulated (IMRT) and stereotactic body radiotherapy with arc therapy (SBRT), and then compared the data with the dose distribution exported from the treatment planning system (Eclipse). Two film analysis softwares were investigated for the comparison: PTW Mephysto and FilmQA Pro. The comparisons of dose distributions were performed with gamma analysis, and the gamma criterion was 3%, 3mm, and 2%, 2mm. The gamma analysis results by the two programs were the following, (PTW/FilmQA Pro) with 3%, 3mm gamma criterion: 3DCRT (95,5/100%), IMRT (97/99,9%), SBRT (99,7/100%). In case of 2%, 2mm the results were: 3DCRT (87,1/98,9%), IMRT (92/98,5%), SBRT (96,7/97,9%). Based on the results it can be stated that during proper use, the features of the scanner do not affect the results. Both evaluation softwares are suitable for calibrating and evaluating films, moreover, performing the gamma analysis. The EBT2 film is suitable for the two-dimensional controlling of radiation therapy plans.