Since the previous decade, the authors introduced the R1 vascular (R1vasc) resection for the treatment of hepatocellular carcinoma (HCC), and colorectal liver metastases (Torzilli et al. J Am Coll Surg 2005; Viganò et al. Ann Surg Oncol 2016; Torzilli et al. Surgery 2017). However, oncological reliability of tumor exposure in surgery for HCC remains controversial since it has never been validated. The aim of the study is to determine the oncological adequacy of R1vasc hepatectomy in patients with HCC.

A prospective cohort of patients who underwent hepatectomy for HCC between January 2005 and December 2015 is reviewed. The following definitions are adopted: R0 is any resection with at least 1 mm of negative margin; R1vasc is any resection with tumor exposure due to the detachment from major intrahepatic vessel (1st/2nd order glissonean pedicles and hepatic vein at caval confluence); R1-parenchymal (R1par) is any resection with tumor exposure at parenchymal margin.

Inclusion Criteria:

• only patients with a primary untreated HCC were included;
• complete follow-up data with available computed tomography (CT) and/or magnetic resonance imaging (MRI) images showing the first recurrence

Exclusion Criteria:

• patients who underwent vascular resection for direct infiltration of the vessel wall
• patients who had radiofrequency ablation in association to surgery

Patients with HCC (hepatocellular carcinoma) who underwent hepatectomy.