A Non-inferiority Study of Indocyanine Green-guided Sentinel Lymph Node Mapping Versus Conventional Lymph Node Dissection in Esophageal Cancer

Indocyanine Green-guided Sentinel Lymph Node Dissection Versus Systematic Lymph Node Dissection in cN0 Esophageal Squamous Cell Carcinoma: a Multicenter, Prospective, Non-inferiority Randomized Controlled Trial

In the comprehensive treatment system for esophageal cancer, surgical resection combined with regional lymph node dissection remains the core component for achieving cure in patients with resectable esophageal squamous cell carcinoma (ESCC). The traditional surgical concept holds that the more thorough the lymph node dissection, the better. However, increasing basic and clinical evidence indicates that lymph nodes without metastasis-particularly tumor-draining lymph nodes-play an irreplaceable role in maintaining the host's anti-tumor immune response. Preclinical studies have found that radiation exposure to tumor-draining lymph nodes can impair the efficacy of radiotherapy combined with immunotherapy. In the surgical field, this shift in understanding has given rise to an important clinical question: in radical esophagectomy for esophageal cancer, is it possible to maximally preserve non-metastatic normal lymph nodes while ensuring complete removal of metastatic lymph nodes? If achievable, patients may not only benefit from reduced postoperative complications (such as chylothorax and recurrent laryngeal nerve injury) but also retain important immune organ function, providing a stronger basis for subsequent immunotherapy responses. Therefore, this study intends to conduct a multicenter, prospective, randomized controlled, non-inferiority trial in patients with cT1-3N0M0 esophageal squamous cell carcinoma who have not received neoadjuvant therapy, to evaluate the oncological safety of sentinel lymph node dissection based on the ICG near-infrared fluorescence imaging system in radical esophagectomy for esophageal cancer.

During the study, ICG will be injected around the tumor under intraoperative gastroscopy guidance, followed by tracking of fluorescent lymph nodes using a thoracoscopic near-infrared camera. Professional thoracic surgeons will group and mark these lymph nodes for intraoperative frozen pathology. If intraoperative frozen section shows negative sentinel lymph nodes, patients will be randomized 1:1 into two groups: one group will undergo esophagectomy alone without further lymph node dissection, while the other group will undergo conventional lymph node dissection plus esophagectomy. The primary objective of this study is to evaluate the non-inferiority of ICG-guided sentinel lymph node dissection compared with conventional systematic lymph node dissection in terms of 3-year disease-free survival in patients with cT1-3N0M0 esophageal squamous cell carcinoma who have not received neoadjuvant therapy, thereby validating the oncological safety of the sentinel lymph node dissection strategy.

Participants will:

1. Undergo minimally invasive ESCC surgery within 2 weeks of enrollment, including the 14th day.
2. Receive ICG injection around the tumor under intraoperative gastroscopy guidance during surgery.
3. Have perioperative, postoperative pathology, and complication information recorded.
4. Undergo standardized follow-up after surgery.

This study will enroll patients with cT1-3N0M0 esophageal cancer who have not received neoadjuvant therapy. If intraoperative frozen section shows negative sentinel lymph nodes, patients will be randomly assigned into two groups: the experimental group will undergo sentinel lymph node dissection only plus esophagectomy, while the control group will undergo conventional lymph node dissection plus esophagectomy. The investigators will compare the 3-year disease-free survival rate, postoperative complication rate, and other outcomes between the two groups to evaluate the oncological safety of sentinel lymph node dissection based on the ICG near-infrared fluorescence imaging system in radical esophagectomy for esophageal cancer.

Inclusion Criteria

1. Aged 18 to 75 years, regardless of gender;
2. Histopathologically confirmed esophageal squamous cell carcinoma or adenocarcinoma by endoscopic biopsy (including esophagogastric junction carcinoma, Siewert type I/II);
3. Preoperative clinical stage cT1-3N0M0 (based on contrast-enhanced CT ± PET-CT ± endoscopic ultrasound evaluation);
4. No prior neoadjuvant therapy of any form (including chemotherapy, radiotherapy, chemoradiotherapy, immunotherapy, targeted therapy, etc.);
5. Scheduled for minimally invasive radical esophagectomy (combined thoracoscopic and laparoscopic McKeown or Ivor-Lewis procedure);
6. No surgical contraindications, with cardiac, pulmonary, hepatic, and renal functions sufficient to tolerate surgery;
7. ECOG performance status score of 0 to 1;
8. Written informed consent signed by the patient or legal representative.

Exclusion Criteria

1. Preoperative imaging clearly indicating lymph node metastasis (cN+) or distant metastasis (cM1);
2. Prior systemic or local treatment for esophageal cancer of any kind (including chemotherapy, radiotherapy, chemoradiotherapy, immunotherapy, etc.);
3. Previous history of esophageal or gastric surgery (except endoscopic mucosal resection/submucosal dissection);
4. History of allergy to iodine contrast agents or indocyanine green;
5. Severe hepatic or renal insufficiency (Child-Pugh class B or C; serum creatinine ≥ 1.5 times the upper limit of normal);
6. Uncontrolled hyperthyroidism;
7. Concomitant other malignancies requiring simultaneous treatment;
8. Pregnant or lactating women;
9. Other conditions deemed unsuitable for enrollment by the investigator.

Withdrawal Criteria

1. Intraoperative exploration revealing inability to achieve radical resection (R2 resection) or extensive thoracic and abdominal metastasis;
2. Intraoperative exploration revealing definite lymph node metastasis (cN+) inconsistent with preoperative staging;
3. Severe allergic reaction after ICG injection requiring discontinuation of the study;
4. Intraoperative change of surgical plan due to severe complications;
5. Withdrawal of informed consent by the patient.