[Analysis of strong invasive clinical features and poor prognosis in macrotrabecular-massive hepatocellular...

Objective: To analyze the correlation between the histological classification of hepatocellular carcinoma (HCC), especially macrotrabecular-massive (MTM), tumor invasiveness, and prognosis. Methods: The clinical and follow-up data of 246 consecutive HCC cases who met the inclusion criteria from 2015 to 2018 were retrospectively analyzed. They were divided into trabecular/pseudoglandular, trabecular/patchy, and MTM types according to the histological classification. The relationship between each type and related clinicopathological features was analyzed. The Kaplan-Meier method was used to plot tumor-free survival (DFS) and overall survival (OS) curves. Log rank tests, COX univariate, and multivariate regression analyses were conducted to analyze the relationship between clinical features, including histological classification, DFS, and OS. Results: Trabecular/pseudoglandular, trabecular/nodular, and MTM type proportions were 44.7% (110 cases), 32.9% (81 cases), and 22.4% (55 cases), respectively. The results of the clinicopathological features showed that MTM-type HCC was significantly more invasive than the other two types, with alpha-fetoprotein (AFP) ≥400 ng/ml, tumor diameter≥8 cm, no tumor capsule, poor differentiation, and MVI positivity proportions, and the differences were statistically significant (P < 0.05).The proportion of MTM-type HCC patients with American Joint Committee on Cancer TNM Stage III to IV and Chinese Liver Cancer Staging (CNLC) II to II was significantly higher than that of the first two types, and the differences were statistically significant (P < 0.05). In addition, the proportion of MTM subtypes undergoing transcatheter arterial chemoembolization was also raised (P < 0.05). The DFS and OS were significantly lower for MTM-type HCC compared to trabecular/pseudoductal-type HCC at 1-, 3-, and 5-years, and the differences were statistically significant (P < 0.05). Univariate analysis indicated that strongly invasive clinical pathological features such as alpha fetoprotein (AFP) ≥400 ng/ml, tumor diameter ≥ 8 cm, no tumor capsule, poor differentiation, positive microvascular invasion, tumor stage, and MTM staging were all risk factors affecting DFS and OS (P < 0.05). Multivariate COX analysis showed that MTM histological staging, AFP ≥ 400 ng/ml, tumor non-encapsulation, satellite nodules, CNLC stages II~III, and TNM stages III~IV were independent risk factors for DFS (P < 0.05), while AFP ≥ 400 ng/ml, tumor non-encapsulation, and CNLC stage II~III were independent risk factors for OS ( P < 0.05). Conclusion: Histological classification is highly correlated with tumor invasiveness and HCC prognosis. Trabecular/pseudoglandular types have lower malignancy and a better prognosis, while MTM types exhibit strong invasive features and a poor prognosis.