Department of Medical Imaging, National Institute of Orthopedics and Traumatology (INTO), Rio de Janeiro, Rio de Janeiro, Brazil.
Department of Medical Imaging, National Institute of Cancer (INCA), Rio de Janeiro, Rio de Janeiro, Brazil.
Br J Radiol. 2021 Aug 1;94(1124):20201391. doi: 10.1259/bjr.20201391. Epub 2021 Jun 19.
This study aims to build machine learning-based CT radiomic features to predict patients developing metastasis after osteosarcoma diagnosis.
This retrospective study has included 81 patients with a histopathological diagnosis of osteosarcoma. The entire dataset was divided randomly into training (60%) and test sets (40%). A data augmentation technique for the minority class was performed in the training set, along with feature's selection and model's training. The radiomic features were extracted from CT's image of the local osteosarcoma. Three frequently used machine learning models tried to predict patients with lung metastases (MT) and those without lung metastases (non-MT). According to the higher area under the curve (AUC), the best classifier was chosen and applied in the testing set with unseen data to provide an unbiased evaluation of the final model.
The best classifier for predicting MT and non-MT groups used a Random Forest algorithm. The AUC and accuracy results of the test set were bulky (accuracy of 73% [ 95% coefficient interval (CI): 54%; 87%] and AUC of 0.79 [95% CI: 0.62; 0.96]). Features that fitted the model (radiomics signature) derived from Laplacian of Gaussian and wavelet filters.
Machine learning-based CT radiomics approach can provide a non-invasive method with a fair predictive accuracy of the risk of developing pulmonary metastasis in osteosarcoma patients.
Models based on CT radiomic analysis help assess the risk of developing pulmonary metastases in patients with osteosarcoma, allowing further studies for those with a worse prognosis.
本研究旨在构建基于机器学习的 CT 放射组学特征,以预测骨肉瘤诊断后发生转移的患者。
本回顾性研究纳入了 81 例经组织病理学诊断为骨肉瘤的患者。整个数据集随机分为训练集(60%)和测试集(40%)。在训练集中对少数类进行了数据扩充技术,同时进行了特征选择和模型训练。从局部骨肉瘤的 CT 图像中提取放射组学特征。尝试使用三种常用的机器学习模型预测有肺转移(MT)和无肺转移(non-MT)的患者。根据较高的曲线下面积(AUC),选择最佳分类器并应用于测试集,以提供对最终模型的无偏评估。
用于预测 MT 和 non-MT 组的最佳分类器使用随机森林算法。测试集的 AUC 和准确性结果较好(准确性为 73%[95%置信区间(CI):54%;87%]和 AUC 为 0.79[95%CI:0.62;0.96])。适合模型的特征(放射组学特征)来自拉普拉斯高斯和小波滤波器。
基于机器学习的 CT 放射组学方法可以提供一种非侵入性方法,具有较高的预测准确性,可以评估骨肉瘤患者发生肺转移的风险。
基于 CT 放射组学分析的模型有助于评估骨肉瘤患者发生肺转移的风险,为预后较差的患者进一步研究提供了依据。