Tumor necrosis as a poor prognostic predictor on postoperative survival of patients with solitary small hepatocellular carcinoma.

Background: Small hepatocellular carcinoma (sHCC) is a special subtype of HCC with the maximum tumor diameter ≤ 3 cm and excellent long-term outcomes. Surgical resection or radiofrequency ablation provides the greatest chance for cure; however, many patients still undergo tumor recurrence after primary treatment. To date, there is no clinical applicable method to assess biological aggressiveness in solitary sHCC.
Methods: In the current study, we retrospectively evaluated tumor necrosis of 335 patients with solitary sHCC treated with hepatectomy between December 1998 and 2010 from Sun Yat-sen University Cancer Center.
Results: The presence of tumor necrosis was observed in 157 of 335 (46.9%) sHCC patients. Further correlation analysis showed that tumor necrosis was significantly correlated with tumor size and vascular invasion (P = 0.026, 0.003, respectively). The presence of tumor necrosis was associated closely with poorer cancer-specific overall survival (OS) and recurrence-free survival (RFS) as evidenced by univariate (P <  0.001; hazard ratio, 2.821; 95% CI, 1.643-4.842) and multivariate analysis (P = 0.005; hazard ratio, 2.208; 95% CI, 1.272-3.833). Notably, the combined model by tumor necrosis, vascular invasion and tumor size can significantly stratify the risk for RFS and OS and improve the ability to discriminate sHCC patients' outcomes (P <  0.0001 for both).
Conclusions: Our results provide evidence that tumor necrosis has the potential to be a parameter for cancer aggressiveness in solitary sHCC. The combined prognostic model may be a useful tool to identify solitary sHCC patients with worse outcomes.