Choong P L, deSilva C J, Dawkins H J, Sterrett G F, Robbins P, Harvey J M, Papadimitriou J, Attikiouzel Y
Department of Electrical & Electronic Engineering, University of Western Australia, Nedlands.
Breast Cancer Res Treat. 1996;37(2):135-49. doi: 10.1007/BF01806495.
Routine axillary dissection is primarily used as a means of assessing prognosis to establish appropriate treatment plans for patients with primary breast carcinoma. However, axillary dissection offers no therapeutic benefit to node negative patients and patients may incur unnecessary morbidity, including mild to severe impairment of arm motion and lymphedema, as a result. This paper outlines a method of evaluating the probability of harbouring lymph node metastases at the time of initial surgery by assessment of tumour based parameters, in order to provide an objective basis for further selection of patients for treatment or investigation. The novel aspect of this study is the use of Maximum Entropy Estimation (MEE) to construct probabilistic models of the relationship between the risk factors and the outcome. Two hundred and seventeen patients with invasive breast carcinoma were studied. Surgical treatment included axillary clearance in all cases, so that the pathologic status of the nodes was known. Tumour size was found to be significantly correlated (P < 0.001) to the axillary lymph node status in the multivariate anlaysis with age (P = 0.089) and vascular invasion (P = 0.08) marginally correlated. Using the multivariate model constructed, 38 patients were predicted to have risk of nodal metastases lower than 20%, of these only 4 (10%) patients had lymph node metastases. A comparison with the Multivariate Logistic Regression (MLR) was carried out. It was found that the predictive quality of the MEE model was better than that of the MLR model. In view of the small sample size, further verification of this model is required in assessing its practical application to a larger population.
常规腋窝清扫术主要用于评估预后，以便为原发性乳腺癌患者制定合适的治疗方案。然而，腋窝清扫术对淋巴结阴性患者并无治疗益处，患者可能会因此遭受不必要的并发症，包括手臂运动的轻度至重度损伤以及淋巴水肿。本文概述了一种通过评估基于肿瘤的参数来评估初次手术时发生淋巴结转移概率的方法，以便为进一步选择治疗或研究患者提供客观依据。本研究的新颖之处在于使用最大熵估计（MEE）来构建风险因素与结果之间关系的概率模型。对217例浸润性乳腺癌患者进行了研究。所有病例均接受腋窝清扫术，因此淋巴结的病理状态已知。在多变量分析中，发现肿瘤大小与腋窝淋巴结状态显著相关（P < 0.001），年龄（P = 0.089）和血管侵犯（P = 0.08）与腋窝淋巴结状态呈边缘相关。使用构建的多变量模型，预测38例患者发生淋巴结转移的风险低于20%，其中只有4例（10%）患者有淋巴结转移。与多变量逻辑回归（MLR）进行了比较。发现MEE模型的预测质量优于MLR模型。鉴于样本量较小，在评估该模型在更大人群中的实际应用时需要进一步验证。
