DOSE AND VOLUME PARAMETERS FOR CT BASED TREATMENT PLANNING IN INTRACAVITARY BRACHYTHERAPY FOR CERVICAL CANCER. A COMPARISON BETWEEN 2D AND 3D BRACHYTHERAPY

作者：Enciu Lucia Elena^*; Constantinescu Amalia; Savu Mircea^*; Baranga Gabriel; Oprea Alexandru; Croitoriu Madalina; Busuioc Laurentiu

来源：Romanian Reports in Physics, 2018, 70(2): 601.

• brachytherapy
• applicators
• organs at risk
• dose-volume histogram

CT-imaging based planning in intracavitary brachytherapy allows optimization of the dose distribution by patient basis. In addition to classical used point dose, the dose-volume histogram (DVH) analysis enables further possibilities for prescribing and reporting the correct dose. A group of 18 patients were treated with 38 fractions using different applicators and CT-based treatment planning. Each application was analyzed in detail. The clinical target volumes were contoured and also the organs at risk. The dose administered to bladder and rectum was analyzed according to ICRU Reports 38 and dose-volume parameters (e.g. D2cc represents the minimal dose for the most irradiated 2 cm(3)). The values of the doses were analyzed including the external beam radiotherapy. Total doses were biologically normalized to conventional 2 Gy fractions (alpha/beta = 10 Gy for target and 3 Gy for organs at risk). Individual changes for active dwell positions and dwell weights are guided by a concept of DVH constraints for target and organs at risk. This helps to detect and avoid the severe overdoses.

• 出版日期2018