Dosimetric Comparison of IMRT Versus 3DCRT for Post-mastectomy Chest Wall Irradiation: An Analytical Observational Study

Purpose: To compare the dose distribution of three-dimensional conformal radiation therapy (3DCRT) with intensity-modulated (IMRT) for post-mastectomy radiotherapy (PMRT) to left chest wall. Materials and Methods: 30 post-MRM female breast cancer patients histologically confirmed infiltrating ductal carcinoma unilateral without evidence distant metastasis or second malignancy were found eligible during January 2017 December 2021. All received 45 Gy in 20 fractions. Planning target volume (PTV) parameters -D2, D98, Dmean, V95, V107—homogeneity index (HI), conformity (CI) compared. The mean doses lung heart, percentage ipsilateral receiving 5 (V5), (V20), 49 (V49) that heart 25 (V25), 42 (V42) extracted from dose-volume histograms Results: PTV comparable between two groups. CI was significantly improved IMRT (1.118 vs. 1.224, p < 0.04) but HI similar (0.0951 0.0962, = 0.125) compared 3DCRT. comparison 3DCRT reduced high-dose volumes (V20, 24.52% 29.62%; V49, 3.56% 6.42%; 0.001) (V25, 5.89% 8.24%; V42, 1.64% 6.12%; 0.001); (10.21 11.96 3.86 7.42 Gy, respectively; 0.001).Conclusions: For sided cancer, improves plan reduce 3DCRT, is superior terms low-dose volume.