全乳切除术后放射治疗对T_(1-2)N_(1)M_(0)期三阴性乳腺癌预后的价值:一项基于监测、流行病学和最终结果数据库的研究

Prognostic value of post-mastectomy radiotherapy in stage T_(1-2)N_(1)M_(0) triple negative breast cancer:a SEER population-based study

目的评价放射治疗对T_(1-2)N_(1)M_(0)期三阴性乳腺癌(TNBC)患者乳房切除术后的预后价值。方法依据纳入、排除标准,选取美国综合国立癌症研究所监测、流行病学和最终结果(SEER)数据库中2010年1月1日至2016年12月31日接受乳房切除的2200例T_(1-2)N_(1)M_(0)期TNBC患者临床资料进行回顾性分析。根据是否接受乳房切除术后放射治疗(PMRT),将患者分为PMRT组和非PMRT组。使用多因素Cox比例风险回归模型评估乳腺癌患者特异性生存(BCSS)率和OS率的独立预后因素。结果本组患者年龄的M(P_(25)~P_(75))为53(43~62)岁,其中PMRT组988例、非PMRT组1212例。中位随访34个月(范围:1~83个月),共死亡389例,其中乳腺癌相关死亡319例。多因素Cox分析结果显示,相比非PMRT组,放射治疗未改善TNBC患者的BCSS和OS(HR=0.81,95%CI:0.64~1.02,P=0.077;HR=0.85,95%CI:0.69~1.05,P=0.129)。分层分析结果显示,PMRT提高了年龄≥60岁者的BCSS率和OS率(HR=0.42,95%CI:0.25~0.69,P=0.001;HR=0.55,95%CI:0.37~0.82,P=0.003);PMRT未能改善T_(2)N_(1)M_(0)期患者的BCSS(HR=0.77,95%CI:0.59~1.00,P=0.050),但能改善OS(HR=0.78,95%CI:0.61~0.99,P=0.038);在未化疗患者中,PMRT改善了患者的OS(HR=0.11,95%CI:0.01~0.79,P=0.028)。结论并非所有接受乳房切除术的T_(1-2)N_(1)M_(0)期TNBC患者都能从PMRT中受益,全身治疗较少或肿瘤较大的患者可能是术后放射治疗的主要受益者,尚需前瞻性临床试验进一步验证。

Objective To investigate prognostic value of post-mastectomy radiotherapy(PMRT)in stage T_(1-2)N_(1)M_(0) triple negative breast cancer(TNBC).Methods According to the inclusion and exclusion criteria,this retrospective study analyzed the clinical data of 2200 patients with stage T_(1-2)N_(1)M_(0) TNBC who received mastectomy from January 1,2010 to December 31,2016 in the Surveillance,Epidemiology,and End Results(SEER)database.The patients were divided into PMRT group and non-PMRT group according to whether PMRT was given.Multivariate Cox proportional hazards model was used to assess the factors related to breast cancer-specific survival(BCSS)and overall survival(OS).Results The age of 2200 patients was 53(43-62)years.There were 988 cases in PMRT group and 1212 cases in non-PMRT group.The median follow-up was 34 months(range:1-83 months).There were 389 death cases,including 319 cancer-related deaths.Multivariate Cox analysis showed that compared with non-PMRT group,radiotherapy did not improve the BCSS(HR=0.81,95%CI:0.64-1.02,P=0.077)and OS(HR=0.85,95%CI:0.69-1.05,P=0.129)in TNBC patients.The results of stratification analysis showed that PMRT improved the BCSS(HR=0.42,95%CI:0.25-0.69,P=0.001)and OS(HR=0.55,95%CI:0.37-0.82,P=0.003)in patients≥60 years;PMRT could not improve BCSS(HR=0.77,95%CI:0.59-1.00,P=0.050)in stage T_(2)N_(1)M_(0) patients,but it improved OS(HR=0.78,95%CI:0.61-0.99,P=0.038).In the patients receiving no chemotherapy,PMRT was significantly associated with a higher OS(HR=0.11,95%CI:0.01-0.79,P=0.028).Conclusions Not all stage T_(1-2)N_(1)M_(0) TNBC patients who underwent mastectomy benefit from PMRT.The patients with less systemic therapy or larger tumor size may benefit more from postoperative radiotherapy.Prospective clinical trials are needed for further validation.