Clinical Experience and Dosimetry Outcome in Treating Breast Cancer with Field-in-Field Technique

摘要

Purpose: The study is aimed to establish the dosimetric characteristics of field-in-field (FiF) technique for carcinoma of breast treatment in Nepal. We assumed that FIF technique may result in improved dose distribution and reduced acute toxicity in these patients. Methods: Forty breast cancer patient s participated in this study. A total dose of 50 Gy in 25 fractions was prescribed to the planning target volume. FiF plan was generated in treatment planning system. Dose volume histograms w ere evaluated for PTV and organs at risks. Several parameters were analyzed for the PTVs and organ at risks (OARs) together with the Conformity index (CI), and the Homogeneity index (HI). Results: The dose coverage of breast volume was achieved. The V _( 95% ) (volume of 95%) of PTV covered D _( 95% ) (Dose of 95%). The PTV dose was covered to 49.98 ± 0.9 Gy and 49.81 ± 1.1 Gy for the left and right breast, respectively. The mean lung dose was 14.87 ± 0.91 Gy. The homogeneity index (0.26 ± 0.17 and 0.22 ± 0.13) and conformity index (1.59 ± 0.75 and 1.36 ± 0.45) were analyzed for left and right breast, respectively. Conclusion: The study supports the viability of FiF technique in the treatment of breast cancer in Nepal. The FIF technique enables better dose distribution in the PTV and reduces dose to OARs. The FiF technique provides dosimetric advantages and requires less planning time.