Hashmi Atif Ali, Faridi Naveen, Khurshid Amna, Naqvi Hanna, Malik Babar, Malik Faisal Riaz, Fida Zubaida, Mujtuba Shafaq
Department of Histopathology, Liaquat National Hospital and Medical College, Karachi, Pakistan.
Asian Pac J Cancer Prev. 2013;14(4):2657-62. doi: 10.7314/apjcp.2013.14.4.2657.
Intraoperative sentinel lymph node biopsy has now become the standard of care for patients with clinically node negative breast cancer for diagnosis and also in order to determine the need for immediate axillary clearance. Several large scale studies confirmed the diagnostic reliability of this method. However, micrometastases are frequently missed on frozen sections. Recent studies showed that both disease free interval and overall survival are significantly affected by the presence of micrometastatic disease. The aim of this study was to determine the sensitivity and specificity of intraoperative frozen section analysis of sentinel lymph nodes (SLNs) for the detection of breast cancer micrometastasis and to evaluate the status of non-sentinel lymph nodes (non-SLNs) in those patients subjected to further axillary sampling.
We performed a retrospective study on 154 patients who underwent SLN biopsy from January 2008 till October 2011. The SLNs were sectioned at 2 mm intervals and submitted entirely for frozen sections. Three levels of each section submitted are examined and the results were compared with further levels on paraffin sections.
Overall 40% of patients (62/154) were found to be SLN positive on final (paraffin section) histology, out of which 44 demonstrated macrometastases (>2mm) and 18 micrometastases (<2mm). The overall sensitivity and specificity of frozen section analysis of SLN for the detection of macrometastasis was found to be 100% while those for micrometastasis were 33.3% and 100%, respectively. Moreover 20% of patients who had micrometastases in SLN had positive non-SLNs on final histology.
Frozen section analysis of SLNs lacks sufficient accuracy to rule out micrometastasis by current protocols. Therefore these need to be revised in order to pick up micrometastasis which appears to have clinical significance. We suggest that this can be achieved by examining more step sections of blocks.
术中前哨淋巴结活检现已成为临床淋巴结阴性乳腺癌患者诊断的标准治疗方法，同时也是为了确定是否需要立即进行腋窝清扫。多项大规模研究证实了该方法的诊断可靠性。然而，在冰冻切片上经常会漏诊微转移。近期研究表明，无病生存期和总生存期均受到微转移疾病存在的显著影响。本研究的目的是确定术中前哨淋巴结（SLN）冰冻切片分析检测乳腺癌微转移的敏感性和特异性，并评估那些接受进一步腋窝取样患者的非前哨淋巴结（非SLN）状态。
我们对2008年1月至2011年10月期间接受SLN活检的154例患者进行了回顾性研究。将SLN以2毫米的间隔切片，并全部送检进行冰冻切片。对送检的每个切片的三个层面进行检查，并将结果与石蜡切片的进一步层面进行比较。
总体而言，在最终（石蜡切片）组织学检查中，40%的患者（62/154）被发现SLN阳性，其中44例显示大转移灶（>2毫米），18例显示微转移灶（<2毫米）。发现SLN冰冻切片分析检测大转移灶的总体敏感性和特异性分别为100%，而检测微转移灶的敏感性和特异性分别为33.3%和100%。此外，SLN中有微转移灶的患者中，20%在最终组织学检查中非SLN呈阳性。
按照当前方案，SLN的冰冻切片分析缺乏足够的准确性来排除微转移。因此，需要对这些方案进行修订，以便发现似乎具有临床意义的微转移。我们建议，可以通过检查更多的组织块连续切片来实现这一点。
