A clinical‐radiomic model for improved prognostication of surgical candidates with colorectal liver metastases

Abstract

Background and ObjectivesColorectal cancer with liver metastases is potentially curable with surgical resection however clinical prognostic factors can insufficiently stratify patients. This study aims to assess whether radiomic features are prognostic and can inform clinical decision making.MethodsThis single‐site retrospective study included 102 patients who underwent colorectal liver metastases resection with preoperative computed tomography (CT), magnetic resonance imaging (MRI) with gadoxetic acid (EOB) and clinical covariates. A lasso‐regularized multivariate Cox proportional hazards model was applied to 114 features (10 clinical, 104 radiomic) to determine association with disease‐free survival (DFS). A prognostic index was derived using the significant Cox regression coefficients and their corresponding input features and a threshold was determined to classify patients into high‐ and low‐risk groups, and DFS compared using log‐rank tests.ResultsFour covariates were significantly associated with DFS; bilobar disease (hazard ratio [HR]= 1.56; P = .0043), complete pathological response (HR= 0.67; P = .025), minimum pixel value (HR= 1.66; P = .00016), and small area emphasis (HR= 0.62; P = .0013) from the EOB‐MRI data. Radiomic CT features were not prognostic. The prognostic index strongly stratified high‐ and low‐risk prognostic groups (HR = 0.31; P = .00068).ConclusionRadiomic MRI features provided meaningful prognostic information above clinical covariates alone. This merits further validation for potential clinical implementation to inform management.

Radiomics of Liver Metastases: A Systematic Review

“…Most papers ( n = 28) described retrospective analyses, while four reported planned secondary analyses of prospectively acquired data [ 32 , 33 , 34 , 35 ]. Nineteen authors analyzed computed tomography (CT) [ 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 ], eight magnetic resonance imaging (MRI) [ 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 ], three positron-emission tomography (PET)/CT [ 59 , 60 , 61 ], and two multiple imaging modalities (CT and MRI; PET and MRI, respectively) [ 62 , 63 ]. Various software applications were used for texture analysis, with these being custom-made in a large proportion of cases ( n = 10).…”

“…Ten studies analyzed radiomic features’ ability to predict the outcome of patients with colorectal LM [ 32 , 33 , 38 , 40 , 43 , 46 , 47 , 59 , 61 , 62 ]. Four included training and validation datasets [ 33 , 37 , 40 , 46 ].…”

“…Four included training and validation datasets [ 33 , 37 , 40 , 46 ]. The endpoint was overall survival (OS) in nine studies [ 32 , 33 , 38 , 40 , 43 , 46 , 47 , 59 , 61 ], progression-free survival (PFS) in four [ 46 , 59 , 61 , 62 ], hepatic PFS in one [ 47 ], and event-free survival in one [ 59 ]. In six papers, patients underwent chemotherapy [ 32 , 33 , 40 , 43 , 46 , 61 ], in two, liver surgery [ 47 , 62 ], and in two, either chemotherapy or surgery [ 38 , 59 ].…”

“…The endpoint was overall survival (OS) in nine studies [ 32 , 33 , 38 , 40 , 43 , 46 , 47 , 59 , 61 ], progression-free survival (PFS) in four [ 46 , 59 , 61 , 62 ], hepatic PFS in one [ 47 ], and event-free survival in one [ 59 ]. In six papers, patients underwent chemotherapy [ 32 , 33 , 40 , 43 , 46 , 61 ], in two, liver surgery [ 47 , 62 ], and in two, either chemotherapy or surgery [ 38 , 59 ]. Six studies analyzed imaging modalities before treatment [ 38 , 43 , 47 , 59 , 61 , 62 ], while four performed comparative analyses of imaging modalities before and after chemotherapy [ 32 , 33 , 40 , 46 ].…”

“…In six papers, patients underwent chemotherapy [ 32 , 33 , 40 , 43 , 46 , 61 ], in two, liver surgery [ 47 , 62 ], and in two, either chemotherapy or surgery [ 38 , 59 ]. Six studies analyzed imaging modalities before treatment [ 38 , 43 , 47 , 59 , 61 , 62 ], while four performed comparative analyses of imaging modalities before and after chemotherapy [ 32 , 33 , 40 , 46 ]. Two studies performed texture analysis not only of LM but also of non-tumoral liver [ 38 , 47 ].…”