The objective of this study is to address the urgent issues in the diagnosis of lymph node metastasis in esophageal cancer. By employing multimodal MRI, spectral CT imaging and FAPI PET-CTtechniques, the study will correlate lymph node images with postoperative pathology results. Additionally, AI technology will be applied to learn from multimodal imaging data, enabling comprehensive analysis and evaluation of lymph node metastasis. Using a large volume of clinical and imaging data, a predictive model will be established to provide individualized lymph node metastasis risk assessments for each esophageal cancer patient. This will, in turn, offer robust support for personalized treatment strategies in esophageal cancer.

Inclusion Criteria:

1. Consecutive patients with pathological diagnosis of esophageal cancer.
2. Patients underwent radical esophagectomy and lymph node dissection, with preoperative multimodal MRI, spectral CT and FAPI PET-CT ; patients underwent neoadjuvant therapy followed by radical surgery, with preoperative multimodal MRI, spectral CT and FAPI PET-CTboth before and after neoadjuvant therapy.
3. No history of malignant tumors or cancer-related treatments.
4. Complete postoperative pathological data, allowing for a one-to-one comparison of preoperative lymph node imaging and postoperative histopathology for evaluation.

Exclusion Criteria:

1. Contraindications for MRI, spectral CT or FAPI PET-CT.
2. Patients who refuse to participate in this study.

Patients are from the Esophageal Cancer Diagnosis and Treatment Center of the Affiliated Tumor Hospital of Zhengzhou University. Data will be collected from Feburary 2025 to January 2030, from patients with biopsy-confirmed esophageal cancer. Based on clinical needs, initial staging will be performed through EUS, spectral CT, or PET-CT. Patients who are planned for direct surgery will undergo MRI within 7 days prior to surgery; patients who are planned for neoadjuvant therapy will undergo spectral CT and MRI examinations both before neoadjuvant therapy and within 7 days before surgery.