Point dose verification in breast cancer radiotherapy: Comparison between 3D conformal and IMRT technique

Abstract

The aim of this work was to verify multi point dose of the 3D-CRT and IMRT in the case of breast cancer. The experiment was perfomed at Siloam Hospital using Linac Trilogy and TPS Eclipse ver. 11. For measurements, Gafchromic film EBT3 was employed in this work in which the EBT3 film was distributed at 5 different points (trachea, axilla, and mammari interna, nipple, mamme inferior). Then, the statistical comparison between the dose measurement between 3D-CRT and IMRT techniques was evaluated. Moreover, the comparison of dose measurement between the non mastectomy and mastectomy group was also carried out. The result of differences in dose shows the trachea dose in the 3D-CRT is smaller than the IMRT in both the non mastectomy and mastectomy patients. The dose at the axilla, internal mammary, nipple, and inferior mammae are greater in the 3D-CRT than IMRT techniques in both non mastectomy and mastectomy patients. The dosage difference between TPS and EBT3 film in the range of from 0.66% to 5.67% (3D-CRT) and -0.67% to -7.57% (IMRT). The statistical test showed there was no difference of mean dose (sig 2 tailed > 0,025) between non mastectomy and mastectomy patients group and 3D-CRT and IMRT.