乳腺癌前哨淋巴结术中分子诊断的研究

Intra-operative GeneSearchTM BLN assay for detecting breast cancer metastases in sentinel lymph nodes

目的 评估乳腺癌前哨淋巴结（SLN）术中分子诊断--GeneSearchTM BLN Assay （BLNa）的诊断价值.方法 2009年2至6月,全国6家乳腺中心的479例乳腺癌患者入组本研究.SLN均垂直于长轴切割为1.5～3 mm组织块,术中奇数组织块行BLNa检测,术后偶数组织块行逐层切片病理检测（采用间隔150 μm的逐层切片HE染色,每个组织块取6张切片）.214例患者的偶数组织块行术中快速冰冻病理（FS）检测,156例患者的所有组织块术中行印片细胞学（TIC）检测.结果 BLNa操作呈现良好的学习曲线,各中心的敏感性和特异性差异均无统计学意义（分别P=0.672;P=0.628）,中位操作时间约35 min.以病例数为统计对象分析,BLNa的准确性、敏感性、特异性、阳性预测值和阴性预测值分别为91.4%、87.5%、92.9%、81.8%、95.3%,其敏感性与FS相似（84.5%,P=0.576）,显著优于TIC（75.0%,P=0.049）.以淋巴结数为统计对象分析,BLNa的准确性、敏感性、特异性、阳性预测值和阴性预测值分别为93.0%、85.6%、94.6%、76.6%、96.9%,其敏感性与FS相似（84.9%,P=0.885）,显著优于TIC（70.0%,P=0.007）.对于伴有宏转移的SLN,BLNa的敏感性为93.6%,与FS相似（95.6%,P=0.558）,显著优于TIC（80.9%,P=0.011）;对于伴有微转移的SLN,BLNa的敏感性为57.5%,有优于FS和TIC的趋势（分别44.4%,P=0.356;30.8%,P=0.094）.结论 GeneSearchTM BLN Assay检测快速,易于操作,具有较高的准确性和可重复性,其敏感性优于FS和TIC,可作为SLN术中诊断的首选.

Objective To evaluate the clinical value of GeneSearchTM BLN Assay as an intraoperative diagnostic method of sentinel lymph node （SLN） for breast cancer patients. Methods A total of 479 consecutive patients from six centers were involved in this prospective study. The SLNs were identified,dissected and then sectioned along the short axis into multiple blocks. The odd blocks were tested intraoperatively by the above-mentioned assay and the even blocks assessed post-operatively by histopathologic examination. The 4 -6 μm thick stepwise sectioning permanent HE slides were prepared every 150 μm and one block yielded 6 slides. In addition, the even blocks of 136 patients were prepared for frozen section （F S） and all blocks of 156 patients evaluated intra-operatively by touch imprint cytology （TIC）. Results In the node basis analysis, its accuracy, sensitivity, specificity, positive predict value （PPV） and negative predict value （NPV） were 93.0%, 85.6%, 94. 6%, 76.6% and 96.9% respectively. Its sensitivity was similar to that of FS （ 84. 9%, P = 0. 885 ） and significantly higher than that of TIC （70. 0%, P = 0. 007 ）.When assessing nodes with macro-metastases, its sensitivity was similar to that of FS （93.6% vs 95.6%,P =0. 558） and significantly higher than that of TIC （93.6% vs 80.9%, P = 0. 011 ）. When assessing nodes with micro-metastases, it had a higher sensitivity than that of FS （57.5% vs 44.4%, P =0. 356） and TIC （57. 5% vs 30. 8%, P =0. 094）. In the patient basis analysis, the accuracy, sensitivity, specificity,PPV and NPV were 91.4%, 87. 5%, 92. 9%, 81.8% and 95. 3% respectively. Its sensitivity was similar to that of FS （84. 5%, P =0. 576） and significantly higher than that of TIC （75.0%, P =0. 049）. After adjustment, it had the accuracy, sensitivity, specificity, PPV and NPV of 91.7%, 83. 5%, 95.2%,88. 3% and 93.0% respectively. Its sensitivity was higher than that of FS （72. 1%, P = 0.054） and significantly higher than that of TIC （ 66. 7%, P= 0. 011 ）. The two had no significant difference in the sensitivity and specificity. After a learning curve of around 10 cases, it could be performed in a median time of around 35 min. The threshold cycle time values of MG and CK-19 were 36 and 31 respectively. The type of metastases could be estimated approximately according to the cycle time values. The cycle time values of MG under 33 indicated SLN macro-metastases and those of 33 - 36 denoted micro-metastases. The values of CK-19 under 29 indicated SLN macro-metastases and those of 29 -31 denoted micro-metastases. Conclusion As an accurate and rapid intra-operative assay for breast sentinel lymph nodes, the GeneSearchTM BLN Assay may replace FS and TIC in general medical practice.