Is CT radiomics superior to morphological evaluation for PN0 characterization? A pilot study in stage II colon adenocarcinoma

Purpose: Lymph node (LN) involvement is among the most important prognostic factors for patients with colon adenocarcinoma (CAC). However, CT morphological analysis is not a reliable method to assess LN status. Thus, we compared morphological and radiomic features extracted from contrastenhanced computed tomography (CECT) images, in assessing locoregional LNs in patients with CAC. Material and Methods: This retrospective study included 45 patients with stage II CAC who underwent preoperative portal-venous phase CT examination and diagnosed as pN0 after surgery. Patients with motion artifacts or lack of pathology report were excluded. Locoregional LNs were scored with a qualitative Likert-scale based on morphological imaging (node score with range 0–5) and divided into two groups: low likelihood (0–2 points) and high likelihood (3–5 points) of malignancy. Then 107 radiomic features were extracted from CECT for each LN. T-test and Mann–Whitney were performed to compare radiomic features between the two groups. P<0.05 was considered significant. Results: A total of 115 negative LNs were analyzed and divided into 48 with low likelihood and 67 with high likelihood of malignancy based on the node score. Radiomic analysis showed 70 features (5/13 shape, 16/19 first-order and 49/75 second-order features) with no significant difference between the two groups, according to pathology (all P>0.05). On the other hand, 37 features (8/13 shape, 3/19 first-order and 26/75 second-order features) were significantly different (all P<0.04). Conclusion: Our preliminary experience showed that CT radiomics characterizes locoregional LN status better than CECT morphological evaluation and could be used as a non-invasive preoperative tool in patients with CAC.