Surgery of small hepatocellular carcinoma. Analysis of 144 cases

Micrometastasis in surrounding liver and the minimal length of resection margin of primary liver cancer

AIM: To describe the distribution of micrometastases in the surrounding liver of patients with primary liver cancer (PLC), and to describe the minimal length of resection margin (RM) for hepatectomy.

METHODS: From November 2001 to March 2003, 120 histologically verfied PLC patients without macroscopic tumor thrombi or macrosatellites or extrahepatic metastases underwent curative hepatectomy. Six hundreds and twenty-nine routine pathological sections from these patients were re-examined retrospectively by light microscopy. In the prospective study, curative hepatectomy was performed from November 2001 to March 2003 for 76 histologically verfied PLC patients without definite macroscopic tumor thrombi or macrosatellites or extrahepatic metastases in preoperative imaging. Six hundreds and forty-five pathological sections from these patients were examined by light microscopy. The resected liver specimens were minutely examined to measure the resection margin and to detect the number of daughter tumor nodules, dominant lesions, and macroscopic tumor thrombi inside the lumens of the major venous system. The paraffin sections were microscopically examined to detect the microsatellites, microscopic tumor thrombi, fibrosis tumor capsules, as well as capsule invasion and the distance of histological spread of the micrometastases.

RESULTS: In the retrospective study, 70 micrometastases were found in surrounding liver in 26 of the 120 cases (21.7%). The farthest distance of histological micrometastasis was 3.5 mm, 5.3 mm and 6.0 mm in 95%, 99% and 100% cases, respectively. Macroscopic tumor thrombi or macrosatellites were observed in 18 of 76 cases, and 149 micrometastases were found in the surrounding live in 25 (43.1%) of 58 cases with no macroscopic tumor thrombi. The farthest distance of histological micrometastasis was 4.5 mm, 5.5 mm and 6.0 mm in 95%, 99% and 100% cases, respectively. Two hundred and sixty-seven micrometastases were found in surrounding liver in 14 (77.8%) out of 18 cases with macroscopic tumor thrombi or macrosatellites. The farthest distance of histological micrometastasis was 18.5 mm, 18.5 mm and 19.0 mm in 95%, 99% and 100% cases, respectively.

CONCLUSION: The required minimal length of RM is 5.5 mm and 6 mm respectively to achieve 99% and 100% micrometastasis clearance in surrounding liver of PLC patients without macroscopic tumor thrombi or macrosatellites, and should be greater than 18.5 mm to obtain 99% micrometastasis clearance in surrounding liver of patients with macroscopic tumor thrombi or macrosatellites.

Hepatectomy for huge hepatocellular carcinoma in 634 cases

AIM: To clarify the safety and feasibility of hepatectomy for huge hepatocellular carcinoma (HCC).

METHODS: A total of 4765 patients with HCC operated at Tongji Hospital were retrospectively studied, of them, 780 patients had huge HCC (10 cm or more in diameter). Hepatectomy was carried out on 634 patients (81.2%). The majority of the liver resection were major resections, and combined resection of the adjacent organs or structures was common (17.2%). The liver resection was combined with portal vein thrombectomy in 139 patients (21.9%).

RESULTS: Postoperative complications were common (26.8%) and required another laparotomy to prevent the complications in 5 patients (0.8%). The 30-d mortality was 2.2%. The main causes of postoperative deaths were liver failure (n = 9), postoperative bleeding (n = 4) and septic complication (n = 1). The 3-, 5- and 10-year survival rates after liver resection were 35.1%, 18.2% and 3.5%, respectively.

CONCLUSION: Hepatectomy for huge HCC is safe and effective. It should be used to treat patients with low surgical risks and resectable tumours.

Ischemic preconditioning protects liver from hepatectomy under hepatic inflow occlusion for hepatocellular carcinoma patients with cirrhosis

AIM: To investigate the protective effect of ischemic preconditioning (IPC) on hepatocellular carcinoma (HCC) patients with cirrhosis undergoing hepatic resection under hepatic inflow occlusion (HIO) and its possible mechanism.

METHODS: Twenty-nine consecutive patients with resectable 0HCC were randomized into two groups: IPC group: before HIO, IPC with 5 min of ischemia and 5 min of reperfusion was given; control group: no IPC was given. Liver functions, hepatic Caspase-3 activity, and apoptotic cells were compared between these two groups.

RESULTS: On postoperative days (POD) 1, 3 and 7, the aspartate transaminase (AST) and alanine transaminase (ALT) levels in the IPC group were significantly lower than those in the control group (P < 0.05). On POD 3 and 7, the total bilirubin level in the IPC group was significantly lower than that in the control group (P < 0.05). On POD 1, the albumin level in the IPC group was higher than that in the control group (P = 0.053). After 1 h of reperfusion, both hepatic Caspase-3 activity and apoptotic sinusoidal endothelial cells in the IPC group were significantly lower than those in the control group (P < 0.05).

CONCLUSION: IPC has a potential protective effect on HCC patients with cirrhosis. Its protective mechanism underlying the suppression of sinusoidal endothelial cell apoptosis is achieved by inhibiting Caspase-3 activity.

Abnormal β-catenin gene expression with invasiveness of primary hepatocellular carcinoma in China

AIM: To study the abnormal expression of β-catenin gene and its relationship with invasiveness of primary hepatocellular carcinoma among Chinese people.

METHODS: Thirty-four hepatocellular carcinoma (HCC) specimens and adjacent paracancerous tissues, 4 normal liver tissues were immunohistochemically stained to study subcellular distribution of β-catenin. Semiquantitive analysis of expression of β-catenin gene exon 3 mRNA was examined by RT-PCR and in situ hybridization. The relationship between expressions of both β-catenin protein, mRNA and clinicopathological characteristics of HCC was also analyzed.

RESULTS: Immunohistochemistry showed that all normal liver tissues and para-cancerous tissues examined displayed membranous type staining for β-catenin protein, occasionally with weak expression in the cytoplasm. While 21 cases (61.8%) of HCC examined showed accumulated type in cytoplasms or nuclei. The accumuled type Labling Index (LI) of cancer tissue and para-cancarous tissue was (59.9 ± 26.3) and (18.3 ± 9.7) respectively (P < 0.01). Higher accumulated type LI was closely related with invasiveness of HCC. Results of RT-PCR showed the β-catenin gene exon 3 mRNA Expression Index (EI) of 34 HCCs was higher than that of para-cancerous tissue and normal liver tissue. Using in situ hybridization, the signal corresponding to β-catenin gene exon 3 mRNA was particularly strong in cytoplasm of HCC when compared with those of para-cancerous and normal liver tissues. Over expression of β-catenin exon 3 was also found to be correlated with high metastatic potential of HCC.

CONCLUSION: Abnormal expression of β-catenin gene may contribute importantly to the invasiveness of HCC among Chinese people.