Investigating the radiation dose to the cervical and thoracic esophagus from post-mastectomy adjuvant radiation therapy in breast cancer

Background: Radiation therapy (RT) plays a crucial role in breast cancer management.However, RT may inadvertently expose neighboring organs to potential adverse effects.This study aimed to quantitatively analyze the radiation dose delivered to the cervical and thoracic esophagus during RT, focusing on patients undergoing postmastectomy adjuvant RT. Materials and Methods: This cross-sectional study included 100 breast cancer patients who underwent post-mastectomy adjuvant RT to the chest wall and supraclavicular field (SCF) using 3-Dimensional Conformal Radiation Therapy (3DCRT).The dosimetric parameters, including mean dose (D mean ), V5, V10 and V30, were estimated from dose-volume histogram (DVH) data for the cervical and thoracic esophagus.Results: The mean age of the patients was 54.01 ( 11.62) years.The Dmean ( SD) for the thoracic and cervical esophagus were 1.15 ( 0.52) and 3.06 ( 2.09), respectively, with statistically significant different doses between the thoracic and cervical esophagus (P-value < 0.001).The V5, V10, and V30 for the thoracic esophagus were zero; however, the V5, V10 and V30 for the cervical esophagus were 7.07 ( 15.83), 2.29 ( 8.04) and 0.29 ( 1.99), respectively.The V5 values were significantly higher than V10 (P-value < 0.001) and V30 (P-value < 0.001), while V10 and V30 did not differ significantly (P-value = 0.155).Conclusions: This study reveals distinct dosimetric patterns for the cervical and thoracic esophagus during RT.The thoracic esophagus received low radiation doses, whereas the cervical esophagus demonstrated higher doses and more significant variability.Findings emphasize the importance of meticulous treatment planning to minimize potential late radiationinduced complications, especially in the cervical region.