Efficacy of postoperative transarterial chemoembolization and portal vein chemotherapy for patients with hepatocellular carcinoma complicated by portal vein tumor thrombosis--a randomized study

Transarterial (chemo)embolisation for unresectable hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) results in more than 600,000 deaths per year. Transarterial embolisation (TAE) and transarterial chemoembolisation (TACE) have become standard loco-regional treatments for unresectable HCC.

OBJECTIVES

To assess the beneficial and harmful effects of TACE or TAE.

SEARCH STRATEGY

We searched The Cochrane Hepato-Biliary Group Controlled Trials Register, The Cochrane Cancer Network register, The Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, EMBASE, Science Citation Index Expanded, and The Latin American Caribbean Health Sciences Literature (LILACS) from dates of inceptions up to September 2010.

SELECTION CRITERIA

We considered for inclusion all randomised trials that compared TACE or TAE versus placebo, sham, or no intervention. Co-interventions were allowed if comparable between intervention groups. Trials with inadequate randomisation were excluded.

DATA COLLECTION AND ANALYSIS

For all-cause mortality, we calculated the log hazard ratio (HR) with standard error as point estimate and pooled them for meta-analysis using the inverse variance method. Sub-group analyses were performed regarding intervention regimen, trial truncation, or co-interventions. We validated the results with trial sequential analyses. We used random-effects model in all meta-analyses in anticipation of statistical heterogeneity among the trials.

MAIN RESULTS

We included nine trials with 645 participants. Six trials assessed TACE versus control and three trials assessed TAE versus control. Seven trials had low risk of selection bias based on adequate generation of allocation sequence and concealment - but all these trials had other risks of bias. Three trials were stopped early due to interim inspections and one due to slow accrual. For all-cause mortality, statistical heterogeneity between trials was low to moderate (I(2)= 30%). Meta-analysis of trials with low risk of selection bias showed that TACE or TAE versus control does not significantly increase survival (HR 0.88; 95% CI 0.71 to 1.10). Two trials with low risk of selection bias, no early stopping, and no co-intervention did not establish any significant effect of TACE or TAE on overall survival (hazard ratio 1.22, 95% confidence interval 0.82 to 1.83; P = 0.33). Trial sequential analysis confirmed the absence of evidence for a beneficial effect of TACE or TAE on survival indicating the need for future randomisation of up to 383 additional participants. Substantial differences in criteria for assessing tumour response did not allow quantitative analyses. One trial investigated quality of life but did not detect any significant differences between the intervention groups. A range of adverse events including post-embolisation syndrome and serious complications were reported.

AUTHORS' CONCLUSIONS

There is no firm evidence to support or refute TACE or TAE for patients with unresectable HCC. More adequately powered and bias-protected trials are needed.

Postoperative adjuvant transarterial chemoembolization for participants with hepatocellular carcinoma: A meta-analysis

AIM

  The efficacy of transarterial chemoembolization (TACE) for inoperable hepatocellular carcinoma (HCC) is positive, but for postoperative HCC, many studies have reported controversial results. The present study aimed to evaluate the efficacy of postoperative adjuvant TACE for participants with HCC.

METHODS

  Electronic and manual searches were conducted to identify randomized controlled trials (RCT) evaluating postoperative adjuvant TACE for participants with HCC.

RESULTS

  Six RCT totaling 659 participants, of whom almost all were of stage IIIA HCC, were included. For the 1-year tumor recurrence rate, hepatectomy plus TACE showed statistically significant less incidence of recurrence, with a pooled risk ratio (RR) of 0.68 (95% confidence interval [CI] = 0.55-0.84, P = 0.0003). For 1-year mortality, the trials were favorable for TACE with a pooled risk ratio of 0.48 (95% CI = 0.35-0.65, P < 0.00001). For 3-year mortality, the trials also revealed statistically significant less incidence, with a pooled risk ratio of 0.76 (95% CI = 0.64-0.90, P = 0.002). However, for 5-year mortality, TACE did not demonstrate statistically significant less incidence (RR = 0.94, 95% CI = 0.81-1.08, P = 0.36). Transient fever and nausea/vomiting were reported as side-effects of TACE but were well tolerated by most participants.

CONCLUSION

  Postoperative adjuvant TACE seems promising for participants with HCC with risk factors (multiple nodules of >5 cm or vascular invasion) but requires further trial.

Surgical treatment of hepatocellular carcinoma with portal vein tumor thrombus

BACKGROUND

The role of liver resection in patients with hepatocellular carcinoma (HCC) accompanying with portal vein tumor thrombus (PVTT) remains controversial. This article aimed to evaluate the significance of different location and extent of PVTT on surgical outcomes after liver resection for HCC.

MATERIALS AND METHODS

A retrospective study was carried out on patients who underwent partial hepatectomy with or without portal thrombectomy for HCC with PVTT in a single tertiary center from January 2001 to December 2003. According to the extent, PVTT was divided into 4 types (I-segmental/sectoral branches of portal vein, II-left and/or right portal vein, III-main portal vein trunk, and IV-superior mesenteric vein).

RESULTS

A total of 406 patients with HCC and PVTT who underwent partial hepatectomy were studied. The complication rate and hospital mortality rate were 32.8 and 0.2%, respectively. After a median follow-up of 6.4 months, 128 patients (31.5%) died. The 1- and 3-year overall survival rates were 34.4 and 13.0%, respectively. The 1- and 3-year disease-free survival rates were 13.3 and 4.7%, respectively. Patients with PVTT located in the segmental, sectoral, or right and/or left portal veins (types I and II) showed significantly better survival than those with PVTT extended to the main trunk of the portal vein or the superior mesenteric vein (types III and IV).

CONCLUSIONS

Liver resection is justified in selected patients with PVTT located in the segmental or sectoral branches of the portal vein. However, surgical resection for PVTT involving the portal bifurcation or the main trunk is still controversial.

Efficacy of a hepatectomy and a tumor thrombectomy for hepatocellular carcinoma with tumor thrombus extending to the main portal vein

INTRODUCTION

Hepatocellular carcinoma (HCC) with major portal tumor thrombus has been considered to be a fatal disease. A thrombectomy remains the only therapeutic option that offer a chance of complete tumor removal avoiding acute portal vein obstruction. However, the efficacy of tumor thrombectomy in addition to hepatectomy has not been well evaluated.

METHODS

Of 979 patients who consecutively underwent initial HCC resection, 45 (4.6%) HCC patients with tumor invasion of the first branch of the portal vein (vp3) and tumor in the main portal trunk or the opposite-side portal branch (vp4) were retrospectively analyzed to evaluate the efficacy of hepatectomy and tumor thrombectomy.

RESULTS

Alpha-fetoprotein, serosal invasion, and intrahepatic metastases were independently significant prognostic factors in all the 45 patients with vp3 or vp4 HCC. The 3- and 5-year survival rates in vp3 and vp4 group were 35.3% and 41.8%, and 21.2% and 20.9%, respectively. There were longer operative times and more intraoperative bleeding in patients with vp4, but no significant difference in mortality, morbidity, and survival between patients with vp3 and vp4.

CONCLUSION

Hepatectomy and thrombectomy for vp4 could not only avoid acute portal occlusion due to tumor thrombus but provide a comparable survival benefit with hepatectomy for vp3.

TACE versus TAE as therapy for hepatocellular carcinoma

Transarterial chemoembolization (TACE) improves survival in cirrhotic patients with hepatocellular carcinoma (HCC). The optimal schedule, best anticancer agent and best technique are still unclear. TACE may not be better than transarterial embolization (TAE). HCC is very chemoresistant, thus embolization may be more important than chemotherapy. Lipiodol cannot be considered as an embolic agent and there are no data to show that it can release chemotherapeutic agents slowly. It can mask residual vascularity on CT imaging and its use is not recommended. Both TACE and TAE result in hypoxia, which stimulates angiogenesis, promoting tumor growth; thus combination of TACE with antiangiogenic agents may improve current results. To date, there is no evidence that TACE pre-liver transplantation or resection helps to expand current selection criteria for patients with HCC, nor results in less recurrence after surgery. Combination with other techniques, such as radiofrequency ablation and drugs, may enhance the effect of TACE. New trials are being conducted to clarify these issues.

Evidence-based diagnosis and locoregional therapy for hepatocellular carcinoma

Early identification of hepatocellular carcinoma (HCC) is crucial to improving the results of therapy and for patients to be eligible for liver transplantation. Recent advances in noninvasive imaging technology include various techniques of harmonic ultrasound, new ultrasound contrast agents, multislice helical computed tomography and rapid high-quality magnetic resonance. The imaging diagnosis relies on the hallmark of arterial hypervascularity with portal venous washout. Since the use of better radiological techniques has improved the accuracy of noninvasive diagnosis, the role of liver biopsy in the diagnosis of HCC has declined. With recent advances in genomics and proteomics, a great number of potential markers have been identified and developed as new candidate markers for HCC. Locoregional therapies currently constitute the best options for early nonsurgical treatment of HCC. Percutaneous ethanol injection shows similar results to resection surgery for single tumors less than 3 cm in diameter. Radiofrequency ablation is superior to percutaneous ethanol injection in terms of local recurrence. Transarterial chemoembolization is currently the most common approach for the management of HCC without curative options since it improves patient survival, but the optimal embolizing agent, length of interval between sessions and whether the chemotherapeutic agent has any effect have not yet been determined. Combining transarterial chemoembolization with antiangiogenic agents, as well as with other techniques, such as radiofrequency ablation, may improve the results. Injection of radioisotopes such as yttrium-90, via the hepatic artery, may be particularly useful in patients with portal vein thrombosis. Comparisons with other transarterial techniques are needed.