Measuring the photon and thermal neutron dose values of contralateral breast surface undergone breast cancer radiation therapy

This research aimed to measure the received photon and thermal neutron doses to contralateral breast (CB) surface in breast cancer radiation therapy for different field sizes in presence of dynamic and physical wedges. The photon and thermal neutron doses were measured by thermo uminescent dosimeter (TLDs) chips for 11 × 13, 11 × 17 and 11 × 21 cm2 field sizes in presence of physical and dynamic wedges. The findings of current study demonstrated that the received doses (both of the photon and thermal neutron) to CB surface in presence of physical wedge for 11 × 13, 11 × 17 and 11 × 21 cm2 field sizes were 12.06, 15.75 and 33.40% of the prescribed dose, respectively, as well as for dynamic wedge were 9.18, 12.92 and 29.26% of the prescribed dose, respectively. The received photon and thermal neutron doses to CB surface increased with increment of field sizes. In addition, the received photon and thermal neutron doses to CB surface in presence of dynamic wedge were less than physical wedge. Similar to recommendations of previous conducted studies, in breast radiation therapy with wedge technique, the using a dynamic wedge is preferable than a physical wedge, especially for medial tangential field.