Vicini Frank A, Kestin Larry, Chen Peter, Benitez Pamela, Goldstein Neal S, Martinez Alvaro
Department of Radiation Oncology, William Beaumont Hospital, Royal Oak, MI 48072, USA.
J Natl Cancer Inst. 2003 Aug 20;95(16):1205-10. doi: 10.1093/jnci/djg023.
Several phase III trials have demonstrated equivalent long-term survival between breast conserving surgery plus radiation therapy and mastectomy in patients with early-stage breast cancer but have not provided information on the optimal volume of breast tissue requiring post-lumpectomy radiation therapy. Therefore, we examined the 5-year results of a single institution's experience with radiation therapy limited to the region of the tumor bed (i.e., limited-field radiation therapy) in selected patients treated with breast-conserving therapy and compared them with results of matched breast-conserving therapy patients who underwent whole-breast radiation therapy.
A total of 199 patients with early-stage breast cancer were treated prospectively with breast-conserving therapy and limited-field radiation therapy using interstitial brachytherapy. To compare potential differences in local recurrence rates based on the volume of breast tissue irradiated, patients in the limited-field radiation therapy group were matched with 199 patients treated with whole-breast radiation therapy. Match criteria included tumor size, lymph-node status, patient age, margins of excision, estrogen receptor status, and use of adjuvant tamoxifen therapy. Local-regional control and disease-free and overall survival were analyzed using the Kaplan-Meier method, and the statistical significance of differences between treatment groups was calculated using the log-rank test. All statistical tests were two-sided.
Median follow-up for surviving patients was 65 months (range = 12-115 months). Five ipsilateral breast failures (i.e., recurrences) were observed in patients treated with limited-field radiation therapy. The cumulative incidence of local recurrence was 1% (95% confidence interval [CI] = 0% to 2.8%). On matched-pair analysis, the rate of local recurrence was not statistically significantly different between the patient groups (1% [95% CI = 0% to 2.4%] for the whole-breast radiation therapy patients versus 1% [95% CI = 0% to 2.8%] for the limited-field radiation therapy patients; P =.65).
Limited-field radiation therapy administered to the region of the tumor bed has comparable 5-year local control rates to whole-breast radiation therapy in selected patients.
多项Ⅲ期试验已证明，早期乳腺癌患者保乳手术加放射治疗与乳房切除术的长期生存率相当，但未提供保乳术后放射治疗所需最佳乳腺组织体积的相关信息。因此，我们研究了一家机构对接受保乳治疗的特定患者采用局限于瘤床区域的放射治疗（即限野放射治疗）的5年结果，并将其与接受全乳放射治疗的匹配保乳治疗患者的结果进行比较。
共有199例早期乳腺癌患者前瞻性地接受了保乳治疗和使用组织间近距离放射治疗的限野放射治疗。为比较基于照射乳腺组织体积的局部复发率的潜在差异，限野放射治疗组的患者与199例接受全乳放射治疗的患者进行匹配。匹配标准包括肿瘤大小、淋巴结状态、患者年龄、切除边缘、雌激素受体状态以及辅助他莫昔芬治疗的使用情况。采用Kaplan-Meier方法分析局部区域控制、无病生存率和总生存率，并使用对数秩检验计算治疗组之间差异的统计学显著性。所有统计检验均为双侧检验。
存活患者的中位随访时间为65个月（范围 = 12 - 115个月）。接受限野放射治疗的患者中观察到5例同侧乳房失败（即复发）。局部复发的累积发生率为1%（95%置信区间[CI] = 0%至2.8%）。在配对分析中，患者组之间的局部复发率在统计学上无显著差异（全乳放射治疗患者为1%[95%CI = 0%至2.4%]，限野放射治疗患者为1%[95%CI = 0%至2.8%]；P = 0.65）。
对瘤床区域进行限野放射治疗，在特定患者中5年局部控制率与全乳放射治疗相当。
