To investigate the correlation between Onodera's Prognostic Nutritional Index (OPNI) and clinicopathological features of hepatocellular carcinoma (HCC) and assess the effect on postoperative tumor recurrence.

Clinicopathological data of 147 patients with HCC admitted to Southeast Hospital affiliated to Xiamen University from January 2018 to December 2021 were retrospectively analyzed. The informed consents of all patients were obtained and the local ethical committee approval was received. Among them, 94 patients were male and 43 female, aged (63±7) years on average. All patients underwent radical surgical resection and were followed up for 3 years or tumor recurrence. The correlation between OPNI and clinicopathological features of HCC patients was carried out by t-test.The receiver operating characteristic (ROC) curve was drawn to analyze the predictive value of OPNI for postoperative recurrence of HCC, and the optimal threshold value was determined. The independent risk factors for postoperative recurrence of HCC were identified by univariate and multivariate Cox analyses. The cumulative recurrence rate was analyzed by Kaplan-Meier method and Log-rank test.

The OPNI of all patients was 45.3±4.0. AFP≥400 μg/L, tumor diameter≥5 cm, poorly differentiated tumor, incomplete tumor capsule, microvascular invasion (MVI), CNLC stage Ⅱ and postoperative recurrence were correlated with the decrease of OPNI (t=3.114, 2.836,-3.009, 2.116, 3.946, 3.273,-7.000. all P<0.05). ROC curve showed that OPNI had predictive value for postoperative recurrence of HCC. The optimal threshold value was 43.5.The area under the ROC curve (AUC) of OPNI was 0.785 (95%CI: 0.708-0.862), the sensitivity was 0.875 and the specificity was 0.682, respectively. Univariate Cox analysis showed that female gender, AFP≥400 μg/L, tumor diameter≥5 cm, incomplete tumor capsule, MVI, CNLC stage Ⅱ, no postoperative interventional therapy and OPNI<43.5 were correlated with high recurrence rate of HCC patients. Multivariate Cox analysis revealed that tumor diameter ≥5 cm (HR=3.464, 95%CI: 1.376-8.716), no postoperative interventional therapy (HR=7.300, 95%CI: 2.415-22.070) and OPNI<43.5 (HR=16.208, 95%CI: 5.586-47.022) were the independent risk factors for postoperative recurrence of HCC. The 3-year cumulative recurrence rate of patients with OPNI<43.5 was 81.81%, and 23.91% for those with OPNI≥43.5, and the difference was statistically significant (χ²=17.177, P<0.001).

Preoperative decrease of OPNI is correlated with poor clinicopathological features in HCC patients. OPNI<43.5 is an independent risk factor for postoperative recurrence of HCC.