*Department of Radiation Oncology, University of Kansas Medical Center, Kansas City, KS †Department of Radiation Oncology, Kimmel Cancer Center ‡Department of Pharmacology and Experimental Therapeutics, Division of Biostatistics, Jefferson Medical College, Thomas Jefferson University, Philadelphia, PA §Department of Radiation Oncology, University of Virginia, Charlottesville, VA.
Am J Clin Oncol. 2014 Jun;37(3):241-7. doi: 10.1097/COC.0b013e318271b326.
We performed a population-based analysis to evaluate changes in patterns of radiation therapy (RT) usage after breast-conserving surgery (BCS) and outcomes among women aged 70 years or older with stage I breast cancer.
We used the Surveillance, Epidemiology and End Results database to identify 33,350 women aged 70 years or older diagnosed from 1990 to 2008 with stage I invasive ductal breast cancer treated with BCS. Patients were stratified by estrogen receptor (ER) status, and classified by RT modality: external beam RT, brachytherapy (BT), other, or none. Usage frequency for each modality was tabulated from 2000 to 2008 subset. Predictors of omission of RT and use of BT were determined by multiple logistic regression. Cox proportional hazard models were created to evaluate the effect of RT usage on breast cancer-specific mortality.
The use of external beam RT decreased during 2000 to 2008. Omission of RT after BCS increased in patients with ER-positive tumors, whereas use of BT increased for both ER-positive and ER-negative tumors. Predictors for the use of BT were later year of diagnosis, metropolitan residence, and highest income quartile. Omission of use of any RT was associated with increased risk of breast cancer-specific mortality among both ER-positive and ER-negative cancers, with greater effect in ER-negative women.
Among older women with stage I breast cancer treated with BCS, use of any RT has been omitted more frequently and BT utilized more often. Further studies are necessary to evaluate potential under-utilization of RT, particularly among women with ER-negative tumors.
我们进行了一项基于人群的分析，以评估保乳手术后（BCS）放射治疗（RT）使用模式的变化，以及 70 岁及以上 I 期乳腺癌女性的治疗结局。
我们使用监测、流行病学和最终结果（SEER）数据库，确定了 1990 年至 2008 年间诊断为 I 期浸润性导管乳腺癌、接受 BCS 治疗且年龄在 70 岁及以上的 33350 名女性。根据雌激素受体（ER）状态对患者进行分层，并根据 RT 方式进行分类：外照射 RT、近距离放疗（BT）、其他或无 RT。从 2000 年至 2008 年的子集中列出每种方式的使用频率。通过多因素逻辑回归确定 RT 遗漏和 BT 使用的预测因素。创建 Cox 比例风险模型评估 RT 使用对乳腺癌特异性死亡率的影响。
2000 年至 2008 年期间，外照射 RT 的使用减少。ER 阳性肿瘤患者 BCS 后 RT 遗漏增加，而 ER 阳性和 ER 阴性肿瘤患者 BT 使用增加。BT 使用的预测因素为诊断年份较晚、居住在大都市地区和收入最高的四分位数。ER 阳性和 ER 阴性肿瘤患者均遗漏任何 RT 的使用与乳腺癌特异性死亡率增加相关，ER 阴性女性的影响更大。
在接受 BCS 治疗的 I 期乳腺癌老年女性中，RT 的使用频率更高，BT 的使用频率更高。需要进一步研究以评估 RT 潜在的利用不足，尤其是在 ER 阴性肿瘤患者中。
