Superior vena cava resection without venous reconstruction for thymic tumors: a report of two cases

Venous reconstruction is required in patients with superior vena cava (SVC) resection to maintain sufficient blood flow to avoid severe complications such as cerebral edema. However, venous reconstruction might not be needed in selected patients with well-established collateral circulations under internal jugular vein pressure (IJVP) monitoring.

In November 2020, a 57-year-old female patient presented with an anterior mediastinal mass after B2 thymoma resection for 8 years. A core needle biopsy suggested recurrence of B2 thymoma. The patient received sequential chemoradiotherapy (SCRT) and had a partial response. She underwent median sternotomy in April 2021. A collateral vessel from left innominate vein was found to descend along the left side of aortic arch. IJVP was 29 cmH₂O after clamping the SVC. The tumor and invaded structures were removed without SVC reconstruction and the azygos vein was reserved. The patient was discharged 8 days after surgery without obstructive symptoms. No tumor recurrence was found after a 44-month follow-up and abundant collateral circulations were found in postoperative imaging. In July 2022, a 56-year-old female patient with B2 thymoma was treated with concurrent chemoradiotherapy and additional 3-cycle chemotherapy before presenting to our hospital. The tumor invaded the SVC and the azygos vein, and there was tumor embolism inside the SVC. Thrombectomy in the SVC was attempted but was unsuccessful. But the IJVP was 25 cmH₂O after clamping the SVC and the azygos vein. Then the SVC, bilateral innominate veins, and azygos vein were resected without venous reconstruction. The patient was discharged 12 days after surgery without severe graft-related complications. After a 31-month follow-up, collateral circulations were more abundant and there was no recurrence of tumor.

To our knowledge, this is the first successful attempt of SVC resection alone without venous reconstruction and we reported long-term results. SVC resection alone under the safe threshold of IJVP was feasible and safe in selected patients with abundant collateral circulations. Patients could benefit from less surgical trauma and be spared of anticoagulants after surgery.