[The effect of different patient positions on overlapping volumes in radiotherapy of patients with high-risk prostate cancer]. / A betegfektetés hatása a védendo szervek és a céltérfogatok átfedésére nagy kockázatú prosztatarákos betegek sugárkezelésekor.

The purpose of the study was to evaluate the relationship among planning target volumes (PTVs) and organs at risk (OARs) based on four different radiotherapy treatment plans for high-risk prostate cancer patients. CT scans were obtained in supine position with knee and ankle support (KAS) and in prone position with belly-board (BB) both with full bladder (FB) and empty bladder (EB). Overlapping volumes of the delineated PTVs and OARs on four different setup combinations (KAS-FB; BB-FB; KAS-EB; BB-EB) were analyzed according to the patient position, bladder filling and circumference of abdomen (CA). Overlapping (∩) was significantly smaller with FB than with EB at the bowels and bladder: PTVpel∩bladder: p=0.0069, PTVpvs∩bladder: p<0.001, PTVp∩bladder: p<0.001, PTVpel∩bowels: p=0.0055. Comparison according to small and large CA resulted in significantly smaller overlapping of PTVs and OARs for large CA patients at: KAS-FB: PTVpel∩rectum: p=0.0255, PTVpvs∩rectum: p=0.0179, PTVp∩rectum: p=0.0386, PTVpel∩bladder: p=0.0355. KAS-EB: PTVpvs∩bladder: p=0.0184, PTVp∩bladder: p=0.0107. BB-EB: PTVpvs∩bladder: p=0.0464, PTVp∩bladder: p=0.0077. The exception was PTVpel∩rectum at KAS-FB where the overlapping were smaller for small CA (p=0.0255). According to our results we recommend to deliver radiotherapy treatment for high-risk prostate cancer patients in supine position with KAS immobilization and full bladder. The overlapping volumes of PTVs and OARs were smaller practically at all patients with larger circumference of abdomen.

[Lens-sparing external beam radiotherapy of periocular lymphomas]. / Szemészeti lokalizációjú lymphomák külso sugárkezelése szemlencsekímélo eljárásokkal.

PURPOSE: The presentation of techniques and results of lens-sparing external beam radiotherapy of patients with ophthalmologic lymphomas. MATERIAL AND METHODS: From 1991 to 2001, at the Department of Radiotherapy of the National Institute of Oncology, Budapest, 92 patients with periocular lymphomas were treated by photon and/or electron beam irradiation depending on the localization. Mean age was 63 years (range: 26-89 years) and the male/female ratio was 1.3. According to the Ann Arbor classification, 72% were in stage I.E. Histologically 85 patients (92.4%) were Grade I while 7 patients (7.6%) presented with higher grade disease. In case of low-grade lymphoma, a dose of 24-32 Gy was delivered, and for higher grade of malignancy we applied 34-40 Gy total dose, using 1.8-2 Gy daily fractions. RESULTS: The local remission rate was 94.4% (CR: 78.8% and PR: 15.6%). There was no change in 2.3%, and 3.3% showed progression. Mild and intermediate acute side effects occurred in 28%, and the incidence of chronic late complications was 3%. CONCLUSION: External beam radiotherapy applying lens-sparing methods is safe and effective in the treatment of periocular lymphomas.

[Computerized radiotherapy planning: retrospective analysis and current methods]. / Számítógépes besugárzástervezés: visszatekintés és korszeru módszerek.

PURPOSE: To present the development of treatment planning methods at the National Institute of Oncology (NIO) from 1969 till 2005. METHODS: The methods and devices of treatment planning is described chronologically. RESULTS: First we did the treatment planning with in-house made devices: body contour drawing instrument, simplified anatomical cross sections, treatment planning table for the cross section projection, archives of isodose curves adjusted to body contours, etc. It was a significant improvement when the graphical addition of isodose curves was followed by computerized dose calculation. In 1978 the work of the Computerized National Treatment Planning Network was started. The Network was organized by IAEA, Ministry of Health Hungary and NIO. The modern treatment planning started at NIO in 1981. From this year, the treatment planning was based on CT, using the CT apparatus of the Medical Postgraduate University. In 1991 a Siemens MEVAPLAN treatment planning system was installed at NIO. The CT data were transferred to the system via floppy disk. The 3D treatment planning program (Pinnacle software of ADAC) started in 2000. The CT, the treatment planning system and newer linear accelerators are connected through the computerized radiotherapy network. Patient positioning, fixing and control devices (mask, EPID etc.) increased the efficacy of the treatment. In-house made devices help this aim too: mirrors at the linear accelerators, special skin marks for CT, block verification unit, multileaf collimator for x-ray treatment simulator. In this year the intensity-modulated radiotherapy (IMRT) will be started at NIO. CONCLUSIONS: The treatment planning at NIO developed to high degree during the investigated time, and it had a considerable effect on the efficacy of radiotherapy.