• Signed written informed consent prior to the initiation of any study-related procedures.

• Age: ≥20 years and ≤75 years, no gender restrictions.

• Diagnosed with esophageal squamous cell carcinoma (ESCC) based on histopathology and imaging, with clinical staging of cT4bN-/+M0 and/or cTanyN+M0 (extracapsular invasion of mediastinal lymph nodes).

• Thoracic segment esophageal squamous cell carcinoma.

• Primary lesion is inoperable or inoperable due to extracapsular invasion of mediastinal lymph nodes.

• ECOG performance status (PS) of 0-1.

• Estimated survival time ≥6 months.

• No prior antitumor therapy for esophageal cancer, including but not limited to chemotherapy, radiotherapy, targeted therapy, or immunotherapy.

• At least one measurable lesion as per RECIST 1.1 criteria.

⁃ No surgical contraindications based on preoperative evaluation of organ function.

⁃ Adequate organ function

⁃ Female participants of childbearing potential must have a negative urine or serum pregnancy test within three days prior to receiving the first dose of study medication (Cycle 1, Day 1). If the urine pregnancy test result is inconclusive, a serum pregnancy test is required. Non-childbearing potential is defined as postmenopausal for at least one year, surgical sterilization, or hysterectomy.

‣ Participants of childbearing potential (male or female) must use highly effective contraception methods (with an annual failure rate \<1%) throughout the study and for 120 days after the last dose of the investigational drug or 180 days after the last dose of chemotherapy, whichever is longer.