Chaddad Ahmad, Daniel Paul, Niazi Tamim
Division of Radiation Oncology, McGill University, Montreal, QC, Canada.
Front Oncol. 2018 Apr 4;8:96. doi: 10.3389/fonc.2018.00096. eCollection 2018.
Colorectal cancer (CRC) is markedly heterogeneous and develops progressively toward malignancy through several stages which include stroma (ST), benign hyperplasia (BH), intraepithelial neoplasia (IN) or precursor cancerous lesion, and carcinoma (CA). Identification of the malignancy stage of CRC pathology tissues (PT) allows the most appropriate therapeutic intervention.
This study investigates multiscale texture features extracted from CRC pathology sections using 3D wavelet transform (3D-WT) filter. Multiscale features were extracted from digital whole slide images of 39 patients that were segmented in a pre-processing step using an active contour model. The capacity for multiscale texture to compare and classify between PTs was investigated using ANOVA significance test and random forest classifier models, respectively.
12 significant features derived from the multiscale texture (i.e., variance, entropy, and energy) were found to discriminate between CRC grades at a significance value of < 0.01 after correction. Combining multiscale texture features lead to a better predictive capacity compared to prediction models based on individual scale features with an average (±SD) classification accuracy of 93.33 (±3.52)%, sensitivity of 88.33 (± 4.12)%, and specificity of 96.89 (± 3.88)%. Entropy was found to be the best classifier feature across all the PT grades with an average of the area under the curve (AUC) value of 91.17, 94.21, 97.70, 100% for ST, BH, IN, and CA, respectively.
Our results suggest that multiscale texture features based on 3D-WT are sensitive enough to discriminate between CRC grades with the entropy feature, the best predictor of pathology grade.
结直肠癌(CRC)具有显著的异质性,通过包括基质(ST)、良性增生(BH)、上皮内瘤变(IN)或癌前病变以及癌(CA)在内的多个阶段逐步发展为恶性肿瘤。识别CRC病理组织(PT)的恶性阶段有助于进行最恰当的治疗干预。
本研究调查了使用三维小波变换(3D-WT)滤波器从CRC病理切片中提取的多尺度纹理特征。多尺度特征是从39例患者的数字全切片图像中提取的,这些图像在预处理步骤中使用主动轮廓模型进行了分割。分别使用方差分析显著性检验和随机森林分类器模型研究了多尺度纹理在PT之间进行比较和分类的能力。
发现从多尺度纹理中得出的12个显著特征(即方差、熵和能量)在校正后以<0.01的显著性值区分CRC分级。与基于单个尺度特征的预测模型相比,组合多尺度纹理特征具有更好的预测能力,平均(±标准差)分类准确率为93.33(±3.52)%,灵敏度为88.33(±4.12)%,特异性为96.89(±3.88)%。发现在所有PT分级中,熵是最佳的分类器特征,ST、BH、IN和CA的曲线下面积(AUC)值平均分别为91.17、94.21、97.70、100%。
我们的结果表明,基于3D-WT的多尺度纹理特征足够敏感,能够利用熵特征区分CRC分级,熵特征是病理分级的最佳预测指标。