An Exploratory Study on the Stable Radiomics Features of Metastatic Small Pulmonary Nodules in Colorectal Cancer Patients

Caiyin Liu; Qiuhua Meng; Qingsi Zeng; Huai Chen; Yilian Shen; Biaoda Li; Renli Cen; Jiongqiang Huang; Guangqiu Li; Yuting Liao; Tingfan Wu

doi:10.3389/fonc.2021.661763

An Exploratory Study on the Stable Radiomics Features of Metastatic Small Pulmonary Nodules in Colorectal Cancer Patients

Front Oncol. 2021 Jul 16:11:661763. doi: 10.3389/fonc.2021.661763. eCollection 2021.

Authors

Caiyin Liu¹, Qiuhua Meng¹, Qingsi Zeng¹, Huai Chen¹, Yilian Shen¹, Biaoda Li², Renli Cen¹, Jiongqiang Huang³, Guangqiu Li⁴, Yuting Liao⁵, Tingfan Wu⁵

Affiliations

¹ Department of Radiology, First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China.
² Department of Radiology, Shenzhen Hospital, University of Hong Kong, Shenzhen, China.
³ Department of Gastrointestinal Surgery, First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China.
⁴ Department of Pathology, First Affiliated Hospital of Guangzhou Medical University, Guangzhou, China.
⁵ Department of Pharmaceutical Diagnostics, GE Healthcare (China), Shanghai, China.

Abstract

Objectives: To identify the relatively invariable radiomics features as essential characteristics during the growth process of metastatic pulmonary nodules with a diameter of 1 cm or smaller from colorectal cancer (CRC).

Methods: Three hundred and twenty lung nodules were enrolled in this study (200 CRC metastatic nodules in the training cohort, 60 benign nodules in the verification cohort 1, 60 CRC metastatic nodules in the verification cohort 2). All the nodules were divided into four groups according to the maximum diameter: 0 to 0.25 cm, 0.26 to 0.50 cm, 0.51 to 0.75 cm, 0.76 to 1.0 cm. These pulmonary nodules were manually outlined in computed tomography (CT) images with ITK-SNAP software, and 1724 radiomics features were extracted. Kruskal-Wallis test was performed to compare the four different levels of nodules. Cross-validation was used to verify the results. The Spearman rank correlation coefficient is calculated to evaluate the correlation between features.

Results: In training cohort, 90 features remained stable during the growth process of metastasis nodules. In verification cohort 1, 293 features remained stable during the growth process of benign nodules. In verification cohort 2, 118 features remained stable during the growth process of metastasis nodules. It is concluded that 20 features remained stable in metastatic nodules (training cohort and verification cohort 2) but not stable in benign nodules (verification cohort 1). Through the cross-validation (n=100), 11 features remained stable more than 90 times.

Conclusions: This study suggests that a small number of radiomics features from CRC metastatic pulmonary nodules remain relatively stable from small to large, and they do not remain stable in benign nodules. These stable features may reflect the essential characteristics of metastatic nodules and become a valuable point for identifying metastatic pulmonary nodules from benign nodules.

Keywords: colorectal cancer; metastases; radiomics; small pulmonary nodules; stable features.