Early Breast Conserving Surgery Intensity Modulatedradiation Therapy Study

Objective: To compare the dosimetric features of early breast-conserving surgery in patients between intensity modulated radiotherapy and conventional radiotherapy. To assess the effects and side effects of intensity-modulated radiotherapy.Methods : From June 2007 to December 2008 admitted to our hospital 36 cases of breast-conserving surgery in patients in this study. To adopt the whole breast in patients with intensity modulated radiotherapy, while treatment planning system to design conventional radiotherapy plan. To compare the uniformity of intensity-modulated radiotherapy and conventional radiotherapy target volume dose distribution and the surrounding normal tissue and organ radiation doses and volume. The same time, acute skin reactions, cosmetic results and short-term effect.Results: Both programs target receiving 95% of the prescribed dose of PTV1 volume ratio(V95)similar comparison between the groups was not statistically significant (P> 0.05). Intensity-modulated treatment plan in 95% of breast volume received 99% of the prescription dose, conventional plan to 98%. Intensity-modulated radiotherapy (IMRT) with conventional radiotherapy (CR) compared to, Dmean closer to the prescribed dosage 5000cGy, and the PTV1 in the IMRT did not accept 110% higher than the prescribed dose volume, PTV 1received at least 105% of the prescribed percentage of irradiated volume (V105)of the average of 1.0% or less, and the CR have more statistically significant difference (P = 0.00). IHI intensity-modulated treatment plans for the 3.2±2.1%, conventional treatment plan for the 28.4±17.1%, the differences were statistically significant, indicating intensity-modulated plans uniformity of the target area significantly better than conventional therapy alone. In the protection of the surrounding normal tissue area, by comparing the lungs Dmean, ipsilateral lung V20, heart Dmean, V40, and contralateral breast Dmean, see intensity-modulated radiotherapy in the lungs, heart and contralateral breast, whether the dose or volume are a significant reduction in all indicators in the comparison between the two groups were significantly different (P <0.01). Occurred during the I-level radiation skin reactions in 5 cases,, II-class skin reaction in 1 case. 8 weeks after the end of radiotherapy skin reactions disappeared. No III, IV-class skin reactions. All patients in the follow-up period were found in the heart and lungs of radioactive toxic reactions (including clinical symptoms and the secondary inspection). Radiotherapy after the end of one year follow-up, when excellent and good rate of 100%. No case of local recurrence in all patients, 1 year local control rate was 100%. 1 year progression-free survival (PFS) was 100%.Conclusion: Early breast conserving surgery three-dimensional conformal intensity modulated radiation therapy compared with conventional radiotherapy, improved target dose distribution, reducing the volume of surrounding normal organs exposed and dosage, side effects of light and improve the quality of life of patients and local control rate .