Potential Impact of the Z0011 Trial on the Omission of Axillary Dissection: A Retrospective Cohort Study

Abstract Objective To evaluate the number of patients with early-stage breast cancer who could benefit from the omission of axillary surgery following the application of the Alliance for Clinical Trials in Oncology (ACOSOG) Z0011 trial criteria. Methods A retrospective cohort study conducted in the Hospital da Mulher da Universidade Estadual de Campinas. The study population included 384 women diagnosed with early-stage invasive breast cancer, clinically negative axilla, treated with breast-conserving surgery and sentinel lymph node biopsy, radiation therapy, chemotherapy and/or endocrine therapy, from January 2005 to December 2010. The ACOSOG Z0011 trial criteria were applied to this population and a statistical analysis was performed to make a comparison between populations. Results A total of 384 patients underwent breast-conserving surgery and sentinel lymph node biopsy. Of the total number of patients, 86 women underwent axillary lymph node dissection for metastatic sentinel lymph nodes (SNLs). One patient underwent axillary node dissection due to a suspicious SLN intraoperatively, thus, she was excluded fromthe study. Among these patients, 82/86 (95.3%) had one to two involved sentinel lymph nodes andmet the criteria for the ACOSOG Z0011 trial with the omission of axillary lymph node dissection. Among the 82 eligible women, there were only 13 cases (15.9%) of lymphovascular invasion and 62 cases (75.6%) of tumors measuring up to 2 cm in diameter (T1). Conclusion The ACOSOG Z0011 trial criteria can be applied to a select group of SLNpositive patients, reducing the costs and morbidities of breast cancer surgery.

摘要 目的：评估符合肿瘤学临床试验联盟（Alliance for Clinical Trials in Oncology，ACOSOG）Z0011试验标准的早期乳腺癌患者，在接受规范治疗后可豁免腋窝手术的患者人群规模。方法：本研究为回顾性队列研究，于坎皮纳斯州立大学妇女医院开展。研究纳入2005年1月至2010年12月期间确诊的384例早期浸润性乳腺癌女性患者，均为临床腋窝淋巴结阴性，接受保乳手术（breast-conserving surgery）、前哨淋巴结活检（sentinel lymph node biopsy）、放射治疗、化疗及/或内分泌治疗。对该研究队列应用ACOSOG Z0011试验标准进行筛选，并开展统计学分析以进行组间比较。结果：共计384例患者接受保乳手术及前哨淋巴结活检。其中86例因前哨淋巴结转移接受腋窝淋巴结清扫（axillary lymph node dissection）；另有1例因术中前哨淋巴结可疑阳性接受腋窝淋巴结清扫，故将其剔除出本研究。在上述86例患者中，82例（95.3%）存在1~2枚受累前哨淋巴结，符合ACOSOG Z0011试验中豁免腋窝淋巴结清扫的标准。在这82例符合条件的女性患者中，仅13例（15.9%）存在脉管癌栓（lymphovascular invasion），62例（75.6%）为肿瘤最大径≤2cm的T1期肿瘤。结论：ACOSOG Z0011试验标准可应用于特定的前哨淋巴结阳性患者群体，能够降低乳腺癌手术的治疗成本与手术相关并发症发生率。