Introduction: Sentinel node biopsy (SNB) has been increasingly performed for patients with lymph node (LN)-positive (cN1) breast cancer that converted to LN-negative (ycN0) status after neoadjuvant chemotherapy (NAC). This study aimed to clarify the SNB avoidance rates using fine needle aspiration cytology (FNAC) for mLNs after NAC. Methods: This study included 68 patients with cN1 breast cancer undergoing NAC from April 2019 to August 2021. Patients with biopsy-proven metastatic clip-marked LNs (clipped LNs) underwent eight cycles of NAC. Ultrasonography (US) was performed to evaluate the effect of the treatment on the clipped LNs, and FNAC was performed after NAC. Patients with ycN0 status determined using FNAC underwent SNB. Those with positive results for FNAC or SNB underwent axillary LNs dissection. Histopathology results and FNA were compared for clipped LNs after NAC. Results: Of the 68 cases, 53 were ycN0 and 15 were clinically positive LNs after NAC( ycN1) on US. Further, 13% (7/53) of all ycN0 and 60% (9/15) of all ycN1 cases showed residual metastasis in the LNs on FNAC. Conclusion: FNAC was diagnostically useful for patients with ycN0 status on US imaging. Using FNAC for LNs after NAC helped to avoid unnecessary SNB in 13% of the cases.


中文翻译：

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针吸细胞学检查对术前化疗证实的转移性淋巴结前哨淋巴结活检的临床影响

简介：前哨淋巴结活检 (SNB) 越来越多地用于淋巴结 (LN) 阳性 (cN1) 乳腺癌患者，这些患者在新辅助化疗 (NAC) 后转变为 LN 阴性 (ycN0) 状态。本研究旨在通过细针抽吸细胞学 (FNAC) 阐明 NAC 后 mLN 的 SNB 避免率。方法：本研究纳入了 2019 年 4 月至 2021 年 8 月期间接受 NAC 的 68 名 cN1 乳腺癌患者。活检证实转移性夹标记淋巴结（夹住 LN）的患者接受了 8 个周期的 NAC。进行超声检查（US）以评估治疗对夹闭的淋巴结的效果，并在 NAC 后进行 FNAC。使用 FNAC 确定 ycN0 状态的患者接受了 SNB。FNAC 或 SNB 结果呈阳性的患者接受了腋窝淋巴结清扫术。比较 NAC 后切除的淋巴结的组织病理学结果和 FNA。结果：68例患者中，53例为ycN0，15例为超声NAC（ycN1）后临床阳性的淋巴结。此外，所有 ycN0 病例中 13% (7/53) 和所有 ycN1 病例中 60% (9/15) 在 FNAC 上显示淋巴结残留转移。结论：FNAC 对于超声成像显示 ycN0 状态的患者具有诊断作用。NAC 之后使用 FNAC 进行 LN 有助于避免 13% 的病例中不必要的 SNB。