Yanming Zhou

Meta-analysis of radiofrequency ablation versus hepatic resection for small hepatocellular carcinoma

BackgroundThere is no clear consensus on the better therapy [radiofrequency ablation (RFA) versus hepatic resection (HR)] for small hepatocellular carcinoma (HCC) eligible for surgical treatments. This study is a meta-analysis of the available evidence.MethodsSystematic review and meta-analysis of trials comparing RFA with HR for small HCC published from 1997 to 2009 in PubMed and Medline. Pooled odds ratios (OR) with 95% confidence intervals (95% CI) were calculated using either the fixed effects model or random effects model.ResultsOne randomized controlled trial, and 9 nonrandomized controlled trials studies were included in this analysis. These studies included a total of 1411 patients: 744 treated with RFA and 667 treated with HR. The overall survival was significantly higher in patients treated with HR than in those treated with RFA at 3 years (OR: 0.56, 95% CI: 0.44-0.71), and at 5 year (OR: 0.60, 95% CI: 0.36-1.01). RFA has a higher rates of local intrahepatic recurrence compared to HR (OR: 4.50, 95% CI: 2.45-8.27). In the HR group the 1, 3, and 5 years disease -free survival rates were significantly better than in the HR-treated patients (respectively: OR: 0.54, 95% CI: 0.35-0.84; OR: 0.44, 95% CI: 0.28-0.68; OR: 0.64, 95% CI: 0.42-0.99). The postoperative morbidity was higher with HR (OR: 0.29, 95% CI: 0.13-0.65), but no significant differences were found concerning mortality. For tumors ≤ 3 cm HR did not differ significantly from RFA for survival, as reported in three NRCTs .ConclusionsHR was superior to RFA in the treatment of patients with small HCC eligible for surgical treatments, particularly for tumors > 3 cm. However, the findings have to be carefully interpreted due to the lower level of evidence.

Sphere-forming cell subpopulations with cancer stem cell properties in human hepatoma cell lines

BackgroundCancer stem cells (CSCs) are regarded as the cause of tumor formation and recurrence. The isolation and identification of CSCs could help to develop novel therapeutic strategies specifically targeting CSCs.MethodsHuman hepatoma cell lines were plated in stem cell conditioned culture system allowed for sphere forming. To evaluate the stemness characteristics of spheres, the self-renewal, proliferation, chemoresistance, tumorigenicity of the PLC/PRF/5 sphere-forming cells, and the expression levels of stem cell related proteins in the PLC/PRF/5 sphere-forming cells were assessed, comparing with the parental cells. The stem cell RT-PCR array was performed to further explore the biological properties of liver CSCs.ResultsThe PLC/PRF/5, MHCC97H and HepG2 cells could form clonal nonadherent 3-D spheres and be serially passaged. The PLC/PRF/5 sphere-forming cells possessed a key criteria that define CSCs: persistent self-renewal, extensive proliferation, drug resistance, overexpression of liver CSCs related proteins (Oct3/4, OV6, EpCAM, CD133 and CD44). Even 500 sphere-forming cells were able to form tumors in NOD/SCID mice, and the tumor initiating capability was not decreased when spheres were passaged. Besides, downstream proteins DTX1 and Ep300 of the CSL (CBF1 in humans, Suppressor of hairless in Drosophila and LAG1 in C. elegans) -independent Notch signaling pathway were highly expressed in the spheres, and a gamma-secretase inhibitor MRK003 could significantly inhibit the sphere formation ability.ConclusionsNonadherent tumor spheres from hepatoma cell lines cultured in stem cell conditioned medium possess liver CSC properties, and the CSL-independent Notch signaling pathway may play a role in liver CSCs.

Meta-Analysis of Laparoscopic Versus Open Resection for Hepatocellular Carcinoma

BackgroundLaparoscopic liver resection (LLR) remains to be established as a safe and effective alternative to open liver resection (OLR) for hepatocellular carcinoma (HCC).AimsThe aim of this meta-analysis is to compare laparoscopic versus open resection for HCC with regard to perioperative and oncologic outcomes.MethodsA literature search was performed to identify comparative studies reporting outcomes for both laparoscopic and open resection for HCC. Pooled odds ratios (OR) and weighted mean differences (WMD with 95% confidence intervals (95% CI) were calculated using either the fixed effects model or random effects model.ResultsTen nonrandomized controlled studies matched the selection criteria and reported on 494 subjects, of whom 213 underwent LLR and 281 underwent OLR for HCC. Compared with the perioperative results of open surgery, reports on laparoscopic resection indicate potentially favourable outcomes in terms of operative blood loss (WMD: −160.57, 95% CI: −246.49 to −74.66), blood transfusion requirement (OR: 0.39, 95% CI: 0.18 to 0.86), postoperative morbidity (OR: 0.48, 95% CI: 0.29 to 0.78), and length of hospital stay (WMD: −5.53, 95% CI: −7.89 to −3.16). Concerning the oncologic outcomes, there was no difference between groups in surgical margin, overall survival and disease-free survival.ConclusionsLLR for HCC is superior to the OLR in terms of its perioperative results and does not compromise the oncological outcomes. Therefore, LLR may be an alternative choice for treatment of HCC.

Laparoscopic versus open distal pancreatectomy: A meta-analysis

OBJECTIVE Laparoscopic distal pancreatectomy (LDP) is a minimally invasive surgical technique. The aim of the present study was to evaluate the currently available literature and compare the short-term clinical outcomes of patients who underwent LDP for left-sided pancreatic pathology with patients who underwent traditional open surgery. METHODS A literature search was performed to identify and compare studies that reported the clinical outcomes of both LDP and open distal pancreatectomy (ODP). Pooled odds ratios (OR) and weighted mean differences (WMD) with 95% confidence intervals (95% CI) were calculated using either fixed-effects or random-effects models. RESULTS Nineteen nonrandomized controlled studies were identified that matched the selection criteria and reported the clinical outcomes of 1935 patients, of whom 805 underwent LDP and 1130 underwent ODP. Compared with open surgery, reports on laparoscopic resection indicate potentially favorable outcomes in terms of operative blood loss (WMD: -273.11; 95% CI: -404.61 to -141.61), the requirement of a blood transfusion (OR: 0.28; 95% CI: 0.11-0.71), postoperative time until oral intake (WMD: -1.19; 95% CI: -1.87 to -0.50), time to first flatus (WMD: -1.03, 95% CI: -1.93 to -0.12), length of hospital stay (WMD: -3.87, 95% CI: -5.06 to -2.68), and overall morbidity (OR: 0.70, 95% CI: 0.56-0.87). There were no differences in terms of the extent of oncologic clearance and postoperative mortality. CONCLUSION LDP results in a faster postoperative recovery and a comparable oncologic clearance in comparison with open surgery. Additional large trials are required to delineate the long-term clinical outcomes of patients diagnosed with malignant neoplasms who undergo either of these two surgeries.

Repeat hepatectomy for recurrent hepatocellular carcinoma: a local experience and a systematic review

BackgroundThis study aimed to assess the efficacy and safety of repeat hepatectomy for recurrent hepatocellular carcinoma (HCC).MethodsThirty-seven patients who underwent a curative repeat hepatectomy in our hospital were retrospectively studied. An extensive database literature search was performed to obtain for all relevant studies.ResultsIn our series, there were no perioperative deaths during repeat hepatectomy for recurrent HCC. Patients survival after repeat hepatectomy were similar to 429 patients undergoing initial hepatectomy. A computerized search of the Medline and PubMed databases found 29 retrospective studies providing relevant data in 1149 patients were included for appraisal and data extraction. After the repeat hepatectomy, postoperative morbidity ranged from 6.2% to 68.2% with a median per cohort of 23.5 per cent. There were 7 perioperative deaths (0.7 per cent of 993 for whom mortality data were provided). The overall median survival ranged from 21 to 61.5 months, with 1 -, 3 -, and 5-year survival of 69.0% to 100%, 21.0% to 87.0%, and 25.0% to 87.0%, respectively.ConclusionsRepeat hepatectomy can be performed safely and is associated with long-term survival in a subset of patients with recurrent HCC. However, the findings have to be carefully interpreted due to the lower level of evidence. A randomized controlled study is needed to compare repeat hepatectomy and other modalities for recurrent HCC.

Outcome of laparoscopic colorectal surgery in obese and nonobese patients: a meta-analysis.

BackgroundObese patients are generally believed to be at increased risk for surgery compared with those who are not obese. A meta-analysis was performed to assess the outcomes of laparoscopic colorectal surgery in obese and nonobese patients.MethodsA systematic literature search from inception to June 2011 was performed. Pooled odds ratios (OR) and weighted mean differences (WMD) with 95% confidence intervals (95% CI) were calculated using the fixed effects model or random effects model.ResultsEight observational studies identified and matched the selection criteria. Conversion rates (OR: 2.31, 95% CI: 1.74–3.08), operating time (WMD: 15.33, 95% CI: 1.81–28.85), and postoperative morbidity (OR: 2.11; 95% CI: 1.3–3.42) were all significantly increased in the obese group. Length of hospital stay and mortality were similar in both groups. For patients with cancer, there was no difference between groups for the number of harvested nodes and length of specimen.ConclusionsObesity is associated with increased conversion rate, operating time, and postoperative morbidity of laparoscopic colorectal surgery but does not affect surgical safety or oncological security.

Hepatitis viruses infection and risk of intrahepatic cholangiocarcinoma: evidence from a meta-analysis

BackgroundStudies investigating the association between Hepatitis B virus (HBV) and hepatitis C virus (HCV) infections and intrahepatic cholangiocarcinoma (ICC) have reported inconsistent findings. We conducted a meta-analysis of epidemiological studies to explore this relationship.MethodsA comprehensive search was conducted to identify the eligible studies of hepatitis infections and ICC risk up to September 2011. Summary odds ratios (OR) with their 95% confidence intervals (95% CI) were calculated with random-effects models using Review Manager version 5.0.ResultsThirteen case–control studies and 3 cohort studies were included in the final analysis. The combined risk estimate of all studies showed statistically significant increased risk of ICC incidence with HBV and HCV infection (OR = 3.17, 95% CI, 1.88-5.34, and OR = 3.42, 95% CI, 1.96-5.99, respectively). For case–control studies alone, the combined OR of infection with HBV and HCV were 2.86 (95% CI, 1.60-5.11) and 3.63 (95% CI, 1.86-7.05), respectively, and for cohort studies alone, the OR of HBV and HCV infection were 5.39 (95% CI, 2.34-12.44) and 2.60 (95% CI, 1.36-4.97), respectively.ConclusionsThis study suggests that both HBV and HCV infection are associated with an increased risk of ICC.

Radiofrequency ablation vs hepatic resection for solitary colorectal liver metastasis: a meta-analysis.

AIM To evaluate the comparative therapeutic efficacy of radiofrequency ablation (RFA) and hepatic resection (HR) for solitary colorectal liver metastases (CLM). METHODS A literature search was performed to identify comparative studies reporting outcomes for both RFA and HR for solitary CLM. Pooled odds ratios (OR) with 95% confidence intervals (95% CI) were calculated using either the fixed effects model or random effects model. RESULTS Seven nonrandomized controlled trials studies were included in this analysis. These studies included a total of 847 patients: 273 treated with RFA and 574 treated with HR. The 5 years overall survival rates in the HR group were significantly better than those in the RFA group (OR: 0.41, 95% CI: 0.22-0.90, P = 0.008). RFA had a higher rate of local intrahepatic recurrence compared to HR (OR: 4.89, 95% CI: 1.73-13.87, P = 0.003). No differences were found between the two groups with respect to postoperative morbidity and mortality. CONCLUSION HR was superior to RFA in the treatment of patients with solitary CLM. However, the findings have to be carefully interpreted due to the lower level of evidence.

Laparoscopic liver resection as a safe and efficacious alternative to open resection for colorectal liver metastasis: a meta-analysis

BackgroundThe safety and efficacy of laparoscopic liver resection (LLR) for colorectal liver metastasis (CLM) remain to be established. A meta-analysis was undertaken to compare LLR and open liver resection (OLR) for CLM with respect to surgical and oncologic outcomes.MethodsAn electronic search was performed to retrieve all relevant articles published in the English language by the end of March 2013. Data were analyzed using Review Manager version 5.0.ResultsA total of 8 nonrandomized controlled studies with 695 subjects were analyzsed. Intra-operative blood loss, the proportion of patients requiring blood transfusion, morbidity and the length of hospital stay were all significantly reduced after LLR. Postoperative recurrence, 5-year overall and disease-free survivals were comparable between two groups.ConclusionsLLR for CLM is safe and efficacious. It improves surgical outcomes and uncompromises oncologic outcomes as compared with OLR.

Perioperative blood transfusion adversely affects prognosis after resection of lung cancer: a systematic review and a meta-analysis

BackgroundIt is speculated that blood transfusion may induce adverse consequences after cancer surgery due to immunosuppression. This study was intended to assess the impact of perioperative blood transfusion on the prognosis of patients who underwent lung cancer resection.MethodsEligible studies were identified through a computerized literature search. The pooled relative risk ratio (RR) with 95% confidence interval (CI) was calculated using Review Manager 5.1 Software.ResultsEighteen studies with a total of 5915 participants were included for this meta-analysis. Pooled analysis showed that perioperative blood transfusion was associated with worse overall survival (RR: 1.25, 95% CI: 1.13-1.38; P <0.001) and recurrence-free survival (RR: 1.42, 95% CI: 1.20-1.67; P <0.001) in patients with resected lung cancer.ConclusionsPerioperative blood transfusion appears be associated with a worse prognosis in patients undergoing lung cancer resection. These data highlight the importance of minimizing blood transfusion during surgery.