الفهرس | Only 14 pages are availabe for public view |
Abstract Summary This study aim to compare the planning efficiency between three dimensional conformal radiotherapy (3D-CRT), inverse planned intensity modulated radiotherapy (IP-IMRT) and field-in-field forward planned intensity modulated radiotherapy (FIF-FP-IMRT) techniques. In this work, twenty patients of breast cancer were reviewed and categorized according to thickness of chest wall, into three groups; small, medium and large. In 3DCRT technique, plans were created by two tangential wedged opposing beams. All the studied groups had achieved good coverage of dose distribution; DR2%R value was in range of (109-110) % of prescribed dose and had achieved good conformity in all chest wall groups. In IP-IMRT technique, two tangential beams and multiple different beams directions were chosen to create IP-IMRT plans and were inversely optimized; all plans had achieved good conformity and homogeneity values. All IP-IMRT plans had DR2%R in range of (107-108) % in medium and large chest wall group while increased it to (111-114) % in small chest wall group. In FiF-FP-IMRT technique, plans were created by combining two open fields with three to four segments in two tangential beam directions, DR2%R had range of (103-105) % of prescribed dose. It achieved good conformity similar to 3DCRT plans but less than IP-IMRT plans in all chest wall groups. The dose delivered to heart, contra-lateral breast, lungs, cord and monitor units were compared among all plans. The obtained results showed that 3DCRT, Tangential IP-IMRT and FIF-FP-IMRT plans had achieved good sparing and lowest dose of critical organs in all chest wall groups. The D5% value of the heart was lower in FIF plans than values with other plans in medium and large chest wall groups. Also the Contra-lateral breast and cord had the lowest dose with 3DCRT, FIF-FP-IMRT and tangential IMRT plans in all chest wall groups. We can conclude that the obtained results showed that, FiF-FPIMRT required less planning time, easy field placements and simple quality assurance. In addition, it provided dosimetric advantages, significantly reducing the size of the hot spot and minimally improving the coverage of the target volume. So, we recommend using this technique in treatment of breast cancer in Radiotherapy hospitals in Egypt. |