Vessels that encapsulate tumor clusters (VETC) is an invasive metastatic factor in HCC independent of the epithelial mesenchyme transition (EMT), and VETC-positive patients have a higher rate of postoperative recurrence. However, it is not clear how the surgical prognosis of VETC-positive patients can be improved.

Previous studies have identified VETC as a new metastatic pattern independent of EMT that may be associated with immunosuppression as well as poor prognosis. Multiple retrospective studies find higher rates of postoperative recurrence, distant metastasis in VETC-positive patients. How to improve surgical prognosis in VETC-positive patients needs to be explored. There is no consensus on postoperative adjuvant therapy for HCC. In recent years, adjuvant immunotherapy (sintilimab) and adjuvant immunotherapy combined with targeted therapy (T+A) have been shown to be effective in improving the surgical prognosis. Therefore, the investigators retrospectively collected three surgical resection cohorts, the surgical resection alone group, the postoperative adjuvant PD-1 monotherapy group, and the postoperative adjuvant PD-1 monotherapy combined with Lenvatinib group, to compare these postoperative adjuvant therapies in a subgroup of VETC patients.

Inclusion Criteria:

• Underwent radical hepatectomy
• No preoperative treatment
• Pathological confirmed HCC
• High-risk recurrent HCC
• Not receiving any adjuvant therapy or receiving adjuvant therapy with PD-1 monotherapy or receiving adjuvant therapy with PD-1 monotherapy in combination with Lenvatinib after surgery

Exclusion Criteria:

• Macrovascular invasion
• No available wax blocks
• No complete clinical information

Patients who met the inclusion and exclusion criteria were retrospectively collected for this study.