早期乳腺癌保乳术后全乳腺调强放疗的临床分析

目的 观察分析早期乳腺癌保乳术后全乳腺调强放疗剂量学优势、临床疗效及不良反应。方法 搜集2004年10月至2005年8月收治的103例早期乳腺癌保乳术后患者,比较全乳腺逆向调强和常规切线野治疗计划靶区的均匀性和心脏、肺受照剂量,以及调强放疗临床不良反应、美容效果及疗效。结果 调强放疗、常规放疗临床靶区的95%~107%处方剂量的平均体积百分比分别为95.8%±4.90%、84.0%±20.7% (t=9.60,P<0.01);同侧受照剂量>20 Gy正常肺组织占全肺体积(V₂₀)的百分比分别为15.70%±4.64%、23.11%±7.88% (t=-13.3,P<0. 01);63例左侧乳腺癌患者心脏V₃₀分别为4.44%±3.93%、15.55%±10.89% (t=-11.3,P<0. 01)。1、2年美容效果优良率均为100%。1、2、3年局部控制率分别为99%、99%、98%;1、2、3年无瘤生存率分别为99%、99%、96%。放疗结束时急性皮肤反应1级98例,2级5例。结论 乳腺癌保乳术后全乳腺调强与常规切线野照射相比,能明显改善靶区剂量分布、保护周围正常组织;局部疗效好,临床不良反应小。

Analysis of dosimetry and clinical outcome using intensity modulated radiation therapy for early breast cancer patients after breast conservative surgery

Objective To analyze the dosimetric benefits,clinical effect and side-respond of whole breast using intensity modulated radiotherapy for early breastcancer after conservative surgery. Methods From Oct.2004 to Aug.2005,103 patients received the whole breast intensity modulated radiation therapy (IMRT). A dosimetric comparison of IMRT with conventional radiotherapy (CR) was performed on each patient. The cosmetic results, clinical effect and side-respond were observed. Results The average volume proportion of 95% and 107% prescribed dose was 95.8%±4.90% and 84.0%±20.7% (t=9.60,P<0.01) with IMRT and CR in clinical target volume, respectively. The V₂₀ (lung volume of accepted>20 Gy/all lung volume×100%) of the ipsilateral lung were 15.70%±4.64% and 23.11%±7.88%(t=-13.3,P<0.01). The V₃₀ of the heart were 4.44%±3.93% and 15.55%±10.89%(t=-11.3,P<0.01) with IMRT and CR respectively for sixty-three left side breast cancer patients. The 1- and 2-year excellent rate of good cosmetic outcome was both 100%. The 1-, 2- and 3-year local control rate was 99%,99% and 98%,respectively. The 1-, 2- and 3-year disease-free survival rate was 99%,99% and 96%,respectively. The Grade 1 and 2 acute radiation skin reaction rate was 95.1% and 4.9%,respectively.Conclusion Compared with conventional radiotherapy, IMRT improves dose distribution of CTV and reduce the dose of normal tissue around CTV; but with better clinical effects and lower side-respond for early breast cancer patients after breast conservative surgery.