乳腺癌保乳术后的放疗技术和适应证

The Radiotherapy after the Conservative Surgery for Patients with Breast Cancer-Technology and Indication

目的:研究IIIa期乳腺癌患者保留乳房术后放疗的疗效,评估术后不同照射剂量和照射野范围的疗效,分析影响预后的独立因素。方法:对照分析139例保乳术后放疗的乳腺癌患者和88例改良根治术后患者的临床资料。保乳术后全乳切线照射46～50Gy(平均剂量49.4Gy),瘤床追加电子束照射10Gy。原位癌均未照射锁骨上野,浸润癌除10例外皆照射锁骨上野(104例)。患侧锁骨上剂量:X线30Gy+电子束20Gy。改良根治术88例患者中,有20例行常规患侧锁骨上野及内乳野照射,另有16例行患侧胸壁及锁骨上野照射,其中有10例行腋下预防照射,剂量50Gy。分析影响预后的独立因素,并评估II-Ia期乳腺癌术后放疗疗效及不同照射剂量和照射野的疗效。结果:IIIa期保乳患者总生存时间与改良根治无明显差异(P>0.05);全乳照射46Gy与50Gy的疗效、不良反应无明显差异;切线野肺受照射<2.5cm,放射性肺炎发生率与受照射2.5～3cm有显著差异(P<0.05);是否照射内乳野对生存时间、局部复发率无明显影响,但照射内乳野可明显增加心肺不良反应的发生率(P<0.05);瘤床放置银夹照射与未放置银夹照射的患者均未发生瘤床复发;分析显示,腋窝淋巴结状态是预后的独立影响因素(P<0.01)。结论:在积极加强化疗及内分泌治疗的基础上,IIIa期患者如有保乳要求,也可试作保乳治疗,但应严格掌握保乳的适应证;切线野照射时,在应受照射区域不漏照的基础上,肺受照射最好小于2～2.5cm;保乳一般不需要照射内乳及腋下;乳腺较小的患者,瘤床手术中放置银夹与否不影响放疗后的局部复发率。

Objective：This study was to evaluate the efficacy of breast conserving operation plus radiotherapy in breast cancer （stage IIIa） and the independent prognosis factor. In addition,we investigate optimized radiation dose and fields. Methods：Cases were patients who received breast-conserving therapy （BCT,n=139） from 2001 to 2008 in our hospital. Control group were patients who received modified radical masectomy （MRM,n=88）. In BCT group,tangential field irradiation was used with dose of 46-50 Gy. Tumor bed was irradiated additional 10 Gy with electron beams. Supraclavicular field irradiation was also used with dose of 50 Gy. Among the 88 cases treated with MRM,20 cases were treated with supraclavicular field irradiation plus internal mammary radiation,and 16 cases were treated with supraclavicular field irradiation plus chest wall. Beside the different doses and fields,the efficacy of radiotherapy for breast cancer （stage IIIa） was estimated. Results：There was no significance difference in survival rate of IIIa stage patients after rational chemotherapy or endocrine therapy between BCT group and MRM group（P0.05）. The efficacy and side-effects were not significantly different between 46 Gy group and 50 Gy group either. moreover we found that internal mammary radiation could contribute to higher incidence rate of adverse effect of lung and heart（P0.05）,but had no effect on survival rate（P0.05）. Additionally,our analysis showed that irradiation dose,whether perform supraclavicular field irradiation or not,and silver clip had no effect on survival rate. Cox regression analysis showed that only axillary lymph node status was an independent prognosis factor（P0.01）. Conclusions：Breast-conserving therapy should be the choice for the patients with breast cancer （stage IIIa） according to the indication. Internal mammary field and axillary field are not advocated in patients with breast cancer. The silver clips have no effect on survival rate of the patients with small breasts.