Department of Surgery, The University of Adelaide, Adelaide, South Australia, Australia.
National Health and Medical Research Council (NHMRC) Clinical Trials Centre, University of Sydney, Sydney, New South Wales, Australia; School of Medicine, University of Notre Dame, Darlinghurst, New South Wales, Australia.
Breast. 2018 Oct;41:82-88. doi: 10.1016/j.breast.2018.05.011. Epub 2018 Jun 26.
Sentinel lymph-node biopsy has reduced the need for extensive axillary surgery for staging. It still exposes women to associated morbidity. Risk models that use clinical and pathology information of the primary tumour to predict sentinel lymph-node metastasis may allow further improvements in care. This study assessed the performance of four published risk models for predicting sentinel lymph-node metastasis in Australian women with early breast cancer; including one model developed in an Australian population.
The Sentinel Node Biopsy Versus Axillary Clearance (SNAC) trial dataset was used to assess model discrimination by calculating the area under the receiver-operating-characteristic curve (AUC) and the false-negative rate for sentinel lymph-node metastasis using model-predicted risk cut-points of 10%, 20%, 30%, and calibration using Hosmer-Lemeshow tests and calibration plots.
The sentinel node was positive in 248 of 982 (25.2%) women (158 macrometastasis, 90 micrometastasis). The AUCs of risk models ranged from 0.70 to 0.74 for prediction of any sentinel-node metastasis; 0.72 to 0.75 for macrometastasis. Calibration was poor for the three models developed outside of Australia (lack-of-fit statistics, P < 0.001). For women with a model-predicted risk of sentinel lymph-node metastasis ≤10%, observed risk was 0-13% (three models <10%), false-negative rate 0-9%; 1-17% of women were classified in this range.
All four models showed good discrimination for predicting sentinel lymph-node metastasis, in particular for macrometastasis. With further development such risk models could have a role in the provision of reassurance to low risk women with normal nodes sonographicaally for whom no axillary surgery is contemplated.
前哨淋巴结活检术减少了广泛的腋窝手术分期的需要。但它仍然使女性面临相关的发病率。使用原发肿瘤的临床和病理信息来预测前哨淋巴结转移的风险模型，可能会进一步改善治疗效果。本研究评估了四个已发表的风险模型在澳大利亚早期乳腺癌女性中预测前哨淋巴结转移的性能；包括一个在澳大利亚人群中开发的模型。
使用 Sentinel Node Biopsy Versus Axillary Clearance (SNAC) 试验数据集来评估模型的区分度，方法是计算曲线下面积（AUC）和使用模型预测的风险切点（10%、20%、30%）的假阴性率，以及 Hosmer-Lemeshow 检验和校准图的校准。
在 982 名女性中，前哨淋巴结阳性 248 例（25.2%）（158 例为宏转移，90 例为微转移）。风险模型预测任何前哨淋巴结转移的 AUC 范围为 0.70 至 0.74；预测宏转移的 AUC 范围为 0.72 至 0.75。澳大利亚以外开发的三个模型的校准效果不佳（拟合优度统计，P<0.001）。对于预测前哨淋巴结转移风险≤10%的女性，观察到的风险为 0-13%（三个模型<10%），假阴性率为 0-9%；在此范围内分类的女性为 1-17%。
所有四个模型在前哨淋巴结转移预测方面都具有良好的区分度，特别是对宏转移。随着进一步的发展，这种风险模型可能在为低风险、超声检查正常淋巴结的女性提供保证方面发挥作用，这些女性不考虑腋窝手术。
