Radiomics Approach for Predicting Esophageal Cancer Pathological Stages Based on MRI

Research Article

Austin J Radiol. 2024; 11(3): 1239.

Radiomics Approach for Predicting Esophageal Cancer Pathological Stages Based on MRI

Rihui Yang1#; Ting Dong2#; Tianhui Zhang1; Weixiong Fan1; Haodong Qin3; Guihua Jiang2*; Haiyang Dai4*

1Department of Radiology, Meizhou People’s Hospital, PR China

2Department of Medical Imaging, Guangdong Second Province General Hospital, PR China

3Siemens Healthineers, Guangzhou, PR China

4Department of Medical Imaging, Huizhou Municipal Central Hospital, PR China

*Corresponding author: Haiyang Dai, Department of Medical Imaging, Huizhou Municipal Central Hospital, No. 41, North Eling Road, Huizhou 516001, PR China; Guihua Jiang, Department of Medical Imaging, Guangdong Second Province General Hospital, Guangzhou, 510317, China. Email: d.ocean@163.com; jianggh@gd2h.org.cn

#These authors have been equally contributed to this article.

Received: July 17, 2024 Accepted: August 14, 2024 Published: August 21, 2024

Abstract

Objective: To explore a rational radiomic approach for predicting preoperative staging and lymph node metastasis based on Magnetic Resonance (MR) images in esophageal cancer patients.

Materials and Methods: This retrospective study included 120 patients (primary cohort: n= 84; validation cohort: n= 36) with esophageal carcinoma confirmed by surgery and pathology. All patients underwent a preoperative MR scan from the neck to the abdomen. For each patient, high throughput and quantitative radiomics features were extracted from T2WI and contrast-enhanced T1WI (T1WI_Gd) images. The radiomics signature of the T2WI and T1WI_Gd images was constructed using minimal redundancy maximal relevance (mRMR) and the least absolute shrinkage and selection operator (Lasso). In addition, associations between the radiomics signature and esophageal cancer staging and lymph node metastasis were explored. Finally, the diagnostic performance of the radiomics approach and tumor volume for discriminating between stages I - II and III - IV and predicting lymph node metastasis was evaluated and compared using the area under the receiver operating characteristic curve (AUC), Sensitivity (SEN), and Specificity (SPE).

Results: A total of 1316 radiomics features were extracted. After feature dimension reduction, eight and nine features were selected for the respective cohorts to build radiomics signatures. Then, based on these signatures, a logistic regression model was built to predict the stages and lymph node metastasis of esophageal cancer. The radiomics signature of T2WI with T1WI_Gd discriminated better the stages and lymph node metastasis in the primary (AUC: 0.884, 0.858; SEN: 0.953, 0.744; SPE: 0.732, 0.829) and validation cohorts (AUC: 0.765, 0.711; SEN: 0.842, 0.952; SPE: 0.647, 0.533).

Conclusions: The MRI-based radiomics signature could identify esophageal cancer stages and lymph node metastasis before treatment.

Keywords: Esophageal cancer; Tumor staging; Lymph node metastasis; Multimodal MRI

Introduction

Esophageal Cancer (EC) is one of the most common malignant gastrointestinal tumors in China, ranking sixth in malignant tumor incidence and fourth in mortality [1], with a five-year survival rate of 19% [2]. Early (stage I - II) esophageal cancer is primarily treated with minimally invasive endoscopic resection or radical surgical resection, while advanced (stage III - IV) esophageal cancer, which has a poor prognosis, is managed with surgical resection after neoadjuvant chemoradiotherapy, or chemoradiotherapy alone [3]. Notably, Lymph Node (LN) involvement is generally associated with worse overall survival [4]. Therefore, predicting EC stages and LN metastasis in patients before treatment is clinically essential. Radiomics is gaining importance in cancer research [5]. High-throughput mining extracts quantitative image features from digitally encrypted medical images, and this is coupled with robust image-based signatures that could potentially enhance precision diagnosis and treatment. Radiomics research recently revealed MRI’s potential to substantially improve the ability to detect or predict LN metastases [4,5]. However, there are no reports on whether a radiomics approach could predict the EC stage based on multimodal MRI.

Computed Tomography (CT), Magnetic Resonance Imaging (MRI), Positron Emission Tomography-CT (PET-CT), and Endoscopic Ultrasonography (EUS) have their respective advantages and disadvantages for evaluating EC preoperative stages and LN status; notably, their sensitivities and specificities are different [6-8]. Currently, the CT-enhanced scan is the most commonly used imaging method for EC diagnosis and efficacy evaluation. However, the detection accuracy of positive LN on preoperative CT remains controversial, and the reported sensitivity, specificity, and accuracy was 37.3-67.2%, 63.9-96.4%, and 85.8-87.2%, respectively [9]. Moreover, the latest version of the Chinese guidelines for EC radiation therapy proposed that the diagnostic value of MRI for LN metastasis was similar to or better than enhanced CT [10].

Relevant studies have shown that radiomics has potential value in predicting tumor stages or LN metastasis [11-13]. However to date, few studies have reported on building models based on MRI radiomics features to predict EC stages and LN metastasis. In this study, the preoperative T2WI and contrast-enhanced T1WI (T1WI_Gd) sequence radiomics features were extracted. We aimed to construct a model to evaluate their value in predicting EC stages and LN metastasis to provide a reference for the clinical treatment of patients.

Result

Clinical Data

The clinicopathologic characteristics of the patients are presented in Table 1. There were no significant differences in age, sex, tumor location, or pathological type between the two groups of patients at EC stages I - II and III – IV, or between the two groups of EC patients with positive and negative LN metastasis (P > 0.05).

Radiomic Features

We used the variance method (excluding variance as 0), mRMR method (select the top 50), and LASSO method (lambda selection standard λ.min) for dimensionality reduction. As a result, eight and nine of 1316 radiomic features were included for EC staging and LN metastasis prediction, respectively. For EC staging, these included logarithm_glcm_Maximum Probability, logarithm_firstorder_Interquartile Range, exponential_glszm_Gray Level Non-Uniformity Normalized, wavelet. HHL_glszm_Size Zone Non-Uniformity Normalized, gradient_glszm_Low Gray Level Zone Emphasis, logarithm_firstorder_Skewness, logarithm_ngtdm_Contrast, logarithm_glcm_Idn. For LN metastasis prediction, these were the included wavelet. LLH_glcm_MCC, wavelet. HHL_glcm_MCC, logarithm_glcm_Maximum Probability, wavelet. HHL_glcm_Imc2, exponential_glszm_Gray Level Non-Uniformity Normalize, gradient_glszm_Low Gray Level Zone Emphasis, logarithm_ngtdm_Contrast, gradient_gldm_Dependence Non-Uniformity Normalized, and logarithm_gldm_Dependence Variance.

The names and descriptions of the selected features are listed in Table 2. Distribution of eight and nine features that could distinguish between stages I - II and III - IV, and positive and negative LN metastasis, were analyzed using the Χ2-test, respectively. Of these, the feature “wavelet.HHL_glcm_Imc2” had a P value < 0.05.