Radiation Dose Burden To The Thyroid Gland Following Postoperative Radiotherapy Of Breast Cancer: A Comparative Dosimetric Study

Abstract

Purpose: To compare and evaluate Thyroid gland radiation doses in intensity modulated radiotherapy (IMRT) and 3D-conformal radiotherapy (3D-CRT) technique for postoperative treatment of breast cancer. Patients and methods: Twenty patients with breast cancer, IMRT and 3D-CRT plans were generated using XIO planning system to analyze and compare with respect to doses to thyroid gland using the parameters (Dmax, Dmin, Dmean, and V5Gy). results: Thyroid radiation doses were more in IMRT than in 3D-conformal technique particularly Dmax in (Breast conservative surgery) BCS cases which showed statistical significance (833.60 ± 38.14 cGy Vs 113.6 ± 12.93 cGy, P-value < 0.05). V5Gy was statistically significant in all cases (7.70 ± 1.43% Vs 0.00%, with P-value = 0.0001). conclusion: IMRT associated with excess radiation doses to thyroid gland than the 3D-conformal technique in postoperative radiotherapy of breast cancer.