Short-term and long-term outcomes of laparoscopic hepatectomy, microwave ablation, and open hepatectomy for small hepatocellular carcinoma: a 5-year experience in a single center

Feasibility, safety, and efficacy of intraoperative magnetic resonance imaging-guided hepatectomy for small hepatocellular carcinoma: A retrospective study

Advancements in diagnostic modalities, such as enhanced magnetic resonance imaging, provide increased opportunities for identifying small hepatocellular carcinoma that is undetectable on preoperative ultrasonography. Whether it is acceptable to leave these lesions untreated is uncertain. This study aimed to evaluate the safety and efficacy of intraoperative magnetic resonance imaging-guided hepatectomy using new navigation systems. This study was conducted between July 2019 and January 2023. We retrospectively studied the clinicopathological features and prognoses of patients with small hepatocellular carcinoma who underwent curative intraoperative magnetic resonance imaging-guided hepatectomy. We evaluated 23 patients (median age, 75 years), among whom 20 (87.0%) were males. Seven (30.4%) and 15 (65.2%) patients had liver cirrhosis and a history of hepatectomy, respectively. The median size of the target lesions was 9 mm, with a median distance of 6 mm from the liver surface. Despite being undetectable preoperatively on contrast-enhanced ultrasonography, all lesions were identified using intraoperative magnetic resonance imaging. Based on pathological findings, 76.0% of the lesions were malignant. The complete resection rate was 100%, and tumor-free margins were confirmed in 96.0% of the patients. Intraoperative magnetic resonance imaging-guided hepatectomy is safe and effective in identifying and resecting small hepatocellular carcinoma lesions that are undetectable on preoperative ultrasonography.

Experimental study for in vitro prostate cancer treatment with microwave ablation and pulsed electromagnetic field

This paper presents the findings of a comprehensive study exploring the synergistic effects arising from the combination of microwave ablation and pulsed electromagnetic field (PEMF) therapy on prostate cancer cells. The research encompassed five distinct experimental groups, with continuous electric field measurements conducted during the entire treatment process. Group 1 and Group 2, subjected to microwave power below 350 W, exhibited specific electric field values of 72,800 V/m and 56,600 V/m, respectively. In contrast, Group 3 and Group 4, exposed to 80 W microwave power, displayed electric field levels of approximately 1450 V/m, while remaining free from any observable electrical discharges. The migratory and invasive capacities of PC3 cells were assessed through a scratch test in all groups. Notably, cells in Group 3 and Group 4, subjected to the combined treatment of microwave ablation and PEMF, demonstrated significantly accelerated migration in comparison to those in Groups 1 and 2. Additionally, Group 5 cells, receiving PEMF treatment in isolation, exhibited decreased migratory ability. These results strongly suggest that the combined approach of microwave ablation and PEMF holds promise as a potential therapeutic intervention for prostate cancer, as it effectively reduced cell viability, induced apoptosis, and impeded migration ability in PC3 cells. Moreover, the isolated use of PEMF demonstrated potential in limiting migratory capacity, which could hold critical implications in the fight against cancer metastasis.

Stage-by-stage analysis of the effect of blood transfusion on survival after curative hepatectomy for hepatocellular carcinoma-a retrospective study

OBJECTIVE

This study is to examine the impact of perioperative (intraoperative/postoperative) blood transfusion on the outcomes of curative hepatectomy for hepatocellular carcinoma. Hepatectomy is a well-established curative treatment for hepatocellular carcinoma, and blood transfusion cannot always be avoided in treating the disease.

METHODS

A retrospective study of patients having curative hepatectomy for hepatocellular carcinoma from January 2010 to December 2019 at a single center was conducted. The patients were stratified by their disease stage. Patients with and without perioperative blood transfusion were matched by propensity-score matching and compared for each disease stage. Univariate and multivariate analyses were performed to identify prognostic factors for overall survival for each stage.

RESULTS

A total of 846 patients were studied. Among them, 125 received perioperative blood transfusion and 720 did not. Patients with blood transfusion had worse disease-free and overall survival. After stratification and matching, the ratios of transfusion to non-transfusion were 33:165 (stage 1), 28:140 (stage 2), and 45:90 (stage 3). Perioperative blood transfusion was associated with a higher incidence of postoperative complications in all three disease stages (p = 0.004/0.006/0.017), and hence longer hospitalization (p < 0.001 in all stages), but had no significant impact on hospital mortality (p = 0.119/0.118/0.723), 90-day mortality (p = 0.259/0.118/0.723), disease-free survival (p = 0.128/0.826/0.511), or overall survival (p = 0.869/0.122/0.122) in any disease stage. Prognostic factors for overall survival included tumor size, tumor number, alpha-fetoprotein level, and postoperative complication of grade ≥ 3A.

CONCLUSION

Perioperative blood transfusion was associated with a higher incidence of complications but had no significant impact on survival after curative hepatectomy for hepatocellular carcinoma.

Clinical Results, Risk Factors, and Future Directions of Ultrasound-Guided Percutaneous Microwave Ablation for Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is one of the most common malignancies worldwide, with a relatively poor prognosis, especially for advanced HCC. With the availability of a variety of treatment options, the treatment strategies for HCC have become more and more diversified. Microwave ablation (MWA) has gradually been considered as a viable alternative to surgical resection (SR) owing to its comparable long-term survival, reduced complications, and greater preservation of hepatic parenchyma. However, clinical outcomes, tumor progression, and recurrence of HCC after MWA remain major concerns. Here, after reviewing the current therapeutic options for HCC, we focus on MWA, describing the advantages and challenges of MWA and the clinical results after treatment. We then focused on prognostic factors that influence post-ablation clinical outcomes and briefly presented the strategy of MWA for future clinical treatment.

Microwave ablation for hepatic malignancies: a systematic review of the technology and differences in devices

BACKGROUND

Microwave ablation (MWA) has become the standard thermal-based treatment for hepatic malignancies in patients who have unresectable disease based on the biology of the tumor, the patients' comorbidities, and certain disease sites. The technical effectiveness, ablation success, local recurrence rates of hepatic malignancies treated with the various commercial microwave ablation devices has not been previously published in the peer reviewed literature. The aim of this systematic review is to summarize the clinical outcomes for the various MWA devices in the use of a hepatic malignancies to best educate hepatic surgeons as well as interventional radiologists.

METHODS

A comprehensive review of the literature and instructions for use of each device that was published from 1/2013 to 12/2020 was performed. The main outcomes extracted were technical success, ablation success, major complications, local and new recurrence rates, recurrence-free survival, ablation volumes, time, and the number of antennas required. A qualitative review of the literature was performed.

RESULTS

In total, 29 studies reporting data on 3250 patients and 4500 tumors were included in this review. Median patient age was 60.5 years (range 3-91). 76.3% (2420 M/753 F) of patients were male. Hepatocellular carcinoma (55%) was the most common tumor pathology followed by colorectal liver metastasis (10%) and cholangiocarcinoma (4%). A majority of studies reported technical success (range, 91.6-100%) and ablation success (range, 73.1-100%), as well as major complications (range, 0-9.1%). Local recurrence (range, 0-50%) was reported by 21 of the studies; however, new recurrence (range, 12.2-64%) was reported less frequently (6 studies) and were further specified in 12, six, and four studies as intrahepatic distant recurrence (11.3-54.2%), extrahepatic distant recurrence (3.6-20%), and metastasis (1.1-36%). A total of three, six, and five studies report disease, progression, and recurrence-free survival rates, respectively.

CONCLUSION

Microwave ablation is frequently used for the treatment of hepatic malignancies. A thorough understanding of the clinical outcomes associated with different pathologies and MWA devices can improve surgeon awareness and help prepare for operative planning and patient management. More consistent reporting of key outcomes in the literature is needed to achieve such an understanding.

Learning curve of microwave ablation for liver cancers

PURPOSE

To evaluate MWA efficacy and safety by cumulative MWA volume and interventional experience.

METHOD

3113 primary liver cancers treated by 7 operators between 2006 and 2018 were studied. Conditional logistic regression was used to estimate within-operators effects of increasing cumulative MWA volume per year on major complication, technical efficacy (TE) and local tumor progression (LTP) rates were adjusted for treatment-level characteristics. Changes were also evaluated by subgroups of tumor size and location.

RESULTS

Lower severe complication rate was detected only in higher MWA volume (HR: 0.31, P = 0.02)). TE rates increased with the increase of MWA volume ((100-150 procedures (HR: 0.33, P = 0.00); 150-200 procedures (HR: 0.08, P = 0.00)) per year. Similar results were found in subgroup analysis of interventional experience (5 to < 10 years (HR: 0.10, P = 0.00). MWA volume per year larger than 150 cases could reduce the major complication rate for tumors smaller than 5 cm (HR: 0.21, P = 0.03) and tumors in higher risk location (HR: 0.18, P = 0.03). The increase of MWA volume per year could significantly increase the TE rate in all tumor size, expect for tumors in high-risk location (100-150 procedures (HR:1.12, P = 0.84), 150-200 procedures (HR: 0.14, P = 0.08)).

CONCLUSIONS

Early and intensive performance of MWA procedures would reduce major complication rates regardless of tumor size and tumor location, but could not improve TE rate in high-risk locations.

Are all local tumour progressions of HCC related to thermal ablation? A study of the causes and classification of local tumour progression

OBJECTIVES

Local tumour progression (LTP) is believed to be a negative consequence of imperfect thermal ablation, but we wondered if all LTP is truly due to imperfect ablation.

METHODS

This study included 185 LTPs occurring within 1 cm of the ablation zone (AZ) after clinical curative thermal ablation for ≤ 5 cm hepatocellular carcinoma between 2010 and 2019. The AZ was divided into 8 quadrants by coronal, sagittal, and horizontal planes. Two methods, visual assessment through pre- and post-MRI (VA) and tumour mapping for 3D visualisation pre- and post-MRI fusion (MF), were used to assess which AZ quadrant included the shortest ablation margin (AM) by three doctors. LTP subclassification was based on whether LTP contacted the AZ margin (contacted LTP and dissociated-type LTP) and occurrence at different time points (12, 18, and 24 months).

RESULTS

Fleiss's Kappa of VA and MF was 0.769 and 0.886, respectively. Cohen's Kappa coefficient between VA and MF was 0.830. For all LTPs, 98/185 (53.0%) occurred in the shortest AM quadrant, which showed a significant central tendency (p < 0.001). However, only 8/51 (15.7%) dissociated - type LTPs and 6/39 (15.4%) LTPs after 24 months occurred in the shortest AM quadrant, which showed no evenly distributed difference (p = 0.360 and 0.303).

CONCLUSIONS

MF is an accurate and convenient method to assess the shortest AM quadrant. LTP is a central tendency in the shortest AM quadrant, but dissociated-type and LTPs after 24 months are not, and these LTP types could be considered nonablation-related LTPs.

KEY POINTS

• LTPs are not evenly distributed around the AZ. More than half of LTPs occur in the shortest AM quadrant. • Subgroup analysis showed that the occurrence of contacted-type LTPs (tumour margin has direct contact with the AZ) within 24 months after ablation indeed had a high proportion in the shortest AM quadrant, and they could be called ablation-related LTPs. • However, the dissociated-type LTPs (tumour margin adjacent to but not in contact with the AZ) or LTPs occurring beyond 24 months after ablation were evenly distributed around the AZ, and they could be called nonablation-related LTPs.

Percutaneous microwave ablation versus robot-assisted hepatectomy for early hepatocellular carcinoma: A real-world single-center study

BACKGROUND

Both microwave ablation and robot-assisted hepatectomy are representative minimally invasive treatments for early hepatocellular carcinoma. Our study compares the practicability and medium-term therapeutic efficacy between them.

METHODS

Patients with early HCC treated by MWA or RH from 2013 to 2019 were included. Propensity score matching (PSM) and inverse probability of treatment weight (IPTW) were used to minimize baseline imbalance. Operation trauma, postoperative recovery, complications, cost and oncological efficacy were compared.

RESULTS

401 patients with a median follow-up of 28 months were included (MWA n = 240; RH n = 161). After PSM, 3-year recurrence-free survival (RFS), overall survival (OS) and cancer-specific survival (CSS) of MWA group and RH group were 52.2% vs 65.8%, 91.5% vs 91.3% and 91.5% vs 91.3%, respectively. OS and CSS were comparable (p = 0.44 and 0.96), while RFS of MWA was slightly lower but not significant (p = 0.097). The above results after IPTW followed the same trend. After PSM, MWA showed advantages in operation time and blood loss, while RH performed better in postoperative liver function. There was no significant difference in incidence of severe complications between two groups.

CONCLUSIONS

For early HCC parents, both treatments can achieve good, safe and comparable medium-term therapeutic effects. MWA is more minimally invasive, while RH has better accuracy and causes less damage to liver parenchyma.

Microwave ablation shows similar survival outcomes compared with surgical resection for hepatocellular carcinoma between 3 and 5 cm

BACKGROUND

Microwave ablation (MWA) is a safe and effective locoregional ablation modality, but it is not clear whether the curative effect of MWA as to hepatocellular carcinoma (HCC) is comparable to that of surgical resection (SR). We aimed to compare the outcomes of MWA and SR for patients with HCC ranging from 3 to 5 cm.

METHODS

197 patients treated for HCC between 3 and 5 cm by MWA or SR were included from 2010 to 2017. Overall survival (OS), progression-free survival (PFS), complication and hospital stay of those patients were compared by using propensity score matching. The registration number of this clinical trial was ChiCTR2000033983.

RESULTS

For patients with HCC between 3 and 5 cm, the 1-, 3-, and 5- years OS rates were 90.3%, 79.7%, and 65.5% in the MWA group, and 96.7%, 88.6%, and 71%% in the SR group, respectively (p = 0.457). The 1-, 3- and 5- years PFS rates were 63.6%, 36.8% and 32.7% in the MWA group, and 74.2%, 41.9% and 35.5% in the SR group, respectively (p = 0.397). The MWA group showed fewer complications (55% versus 78.8%, p = 0.041) and shorter hospital stays (8 versus 15 days, p < 0.001) compared with the SR group.

CONCLUSION

MWA showed similar survival outcomes compared with SR for HCCs ranging from 3 to 5 cm. However, it showed favorable results in terms of hospital stay and complication rate compared to SR.

Surgical Resection: Old Dog, Any New Tricks?

Patients with hepatocellular carcinoma (HCC) have many treatment options. For patients with surgical indication, consideration of future liver remnant and the surgical complexity of the procedure is essential. A new 3-level complexity classification categorizing 11 liver resection procedures predicts surgical complexity and postoperative morbidity better than reported classifications. Preoperative portal vein embolization can mitigate the risk of hepatic insufficiency. For small HCCs, both liver resection and ablation are effective. New medical treatment options are promising and perioperative use of these drugs may further improve outcomes for patients undergoing liver resection and lead to changes in current treatment guidelines.

Value of MRI/CT Image Fusion for Targeting "invisible" Lesions in Stereotactic Microwave Ablation (SMWA) of Malignant Liver Lesions: A Retrospective Analysis

PURPOSE

To assess the technical feasibility of MRI/CT image fusion and completeness of ablation treatment for primary or metastatic liver lesions invisible on contrast-enhanced CT planning scans and outcome in patients treated with stereotactic microwave ablation (SMWA).

MATERIALS AND METHODS

The study was approved by the local ethics committee. Patients who underwent SMWA between January 2015 and December 2018 were retrospectively analyzed. All liver lesions for which MRI/CT fusion was performed due to invisibility on pre-interventional CT planning scans were included and reassessed. The outcome measurement was successful ablation of the lesion at first follow-up imaging.

RESULTS

During the study period, 236 patients underwent 312 SMWAs with ablation of 496 lesions. Twenty-four lesions in 15 patients (mean age, 62 years; range, 43-80 years) were included. Following MRI/CT image fusion, all 24 lesions could be sufficiently localized to perform SMWA. The first follow-up imaging showed complete ablation of 22 lesions. Two initially incompletely ablated lesions were hepatocellular carcinomas and were successfully re-ablated afterwards.

CONCLUSION

SMWA with MRI/CT image fusion is an accurate and safe treatment option for patients with liver lesions not detectable on contrast-enhanced CT planning scans. MRI/CT image fusion may allow more patients with malignant liver lesions to benefit from local ablation treatment even if their lesions are not visible on CT planning examinations.

Microwave ablation of liver cancer: An updated review

The treatment methods for early liver cancer include surgical resection, liver transplantation, and local ablation. Among them, microwave ablation (MWA) is widely used in clinical practice because of its outstanding advantages, such as minimal invasiveness, radical curative effect, short treatment time, few complications, and no heat-sink effect, especially for the treatment of tumors adjacent to major vessels and hepatic metastases. However, MWA also has limitations such as unpredictable size and shape of the ablation area. This review systematically illustrates the effectiveness and safety of MWA in the treatment of liver cancer. Meanwhile, the relative superiority of the new generation of MWA is discussed, with an aim to provide reference for MWA of liver cancer.

The efficacy of microwave ablation versus liver resection in the treatment of hepatocellular carcinoma and liver metastases: A systematic review and meta-analysis

BACKGROUND

Microwave ablation (MWA) is an important method in the treatment of liver cancer. This systematic review compared MWA with liver resection (LR) for liver cancer treatment. In recent years, the MWA has been also reported to play an important role. Studies comparing MWA and LR are lacking. This study aims to compare the efficacy of MWA and LR in the treatment of hepatocellular carcinoma (HCC).

METHODS

A systematic search of PubMed, Embase, Cochrane Library and Web of Science up to April 1, 2019 was conducted for relevant studies that compared the efficacy of MWA and LR in the treatment of HCC. The primary outcomes were local tumor recurrence (LTR) and overall survival (OS) of patients. The secondary outcomes included disease free survival (DFS), extrahepatic metastasis, intrahepatic de novo lesions, length of stay, complications, intraoperative blood loss and operative time.

RESULTS

A total of 16 studies including 2622 patients were identified. Incidence of LTR was significantly higher in patients with MWA than LR, with a pooled OR of 2.69 (95% CI 1.33-5.41; P = 0.006). No significant difference in 1-year OS was found. However, patients with MWA experienced higher 3- and 5-year OS, with pooled ORs of 1.40 (95% CI 1.07-1.84; P = 0.01) and 1.41 (95% CI 1.10-1.80; P = 0.007) respectively. In secondary measures, the 1- and 3-year DFS were significantly higher in patients with MWA. However, no significant difference of 5-year DFS was observed. In addition, lower incidence of complications, less intraoperative blood loss and shorter operative time and shorter length of stay were observed in MWA.

CONCLUSIONS

Though MWA may lead to higher incidence of recurrence, it may be an effective and safe alternative in patients with HCC or liver metastases. MWA may have benefits in patients' survival and safety. Randomized studies should be performed to determine the target population that benefits most from MWA in the future.

Influence of hepatic neoplasia on life expectancy in dogs

BACKGROUND AND AIM

The present study investigated the influence of liver tumor structure on life expectancy in dogs. Diseases of the liver comprise 5-25% of all non-communicable diseases in dogs, and primary hepatic tumors account for 0.6-1.3% of tumors. This research aimed to study the post-operative life span of animals with primary or metastatic tumors of the liver.

MATERIALS AND METHODS

During the study period, 7124 oncological operations were performed in our clinic. In total, 128 liver tumors were detected in live animals, while 323 were detected posthumously. Forty animals underwent surgery for various liver tumors. In dogs with primary liver tumors, the average age was 11.9 years and the average body weight was 15.5 kg, while in dogs with liver metastases, the mean age was 11.4 years and the average body weight was 24 kg.

RESULTS

The ratio of males to females among dogs with primary liver tumors was about 1:1 (ten females and nine males), while that among dogs with metastatic liver damage was clearly predominantly female (14 females and two males) because females often undergo surgery for cancerous mammary glands or ovaries.

CONCLUSION

The size of tumors and the number of affected lobes had a significant effect on the post-operative life span. With a tumor size of <5 cm and a lesion covering less than two lobes of the liver, life expectancy was significantly longer and the prognosis was more favorable. In cases of large tumors or those affecting more than two lobes, life expectancy was significantly reduced and the prognosis was cautious to unfavorable.

Totally laparoscopic anatomic S7 segmentectomy using in situ split along the right intersectoral and intersegmental planes

BACKGROUND

The traditional open or laparoscopic segmentectomy of liver segment 7 (S7) requires exposing and controlling the root of the right hepatic vein(RHV)after full mobilization and lifting up of the right liver before liver transection. This approach violates the "no-touch" principle for malignant tumors, and makes laparoscopic resection technically challenging. So reports on isolated totally laparoscopic anatomic S7 segmentectomy have rarely been reported. This study describes our experience in laparoscopic anatomic S7 segmentectomy using in situ split along the right intersectoral and intersegmental planes of the liver. To our knowledge, this is the first description of this novel approach.

METHODS

From September 2017 to May 2019, patients who underwent laparoscopic anatomic S7 segmentectomy for hepatocellular carcinoma at the HPB Surgery Department, Sun Yat-Sen Memorial Hospital entered into this retrospective study. This in situ split approach was designed using main vessels as the plane markers of right intersectoral and intersegmental planes, along which liver transection was carried out. There was no need to mobilize the right liver and control the root of RHV.

RESULTS

There were 9 women and 15 men. The average diameter of the tumors on preoperative CT/MR was 3.4 cm (range 2-6 cm). All the procedures were successfully carried out laparoscopically. There was no perioperative death. The average operative time was 216.5 min (range 180-310 min). The average blood loss was 320 ml (range 120-620 ml). Pathological study showed all the operations to be R0 resections.

CONCLUSION

Laparoscopic anatomic S7 segmentectomy using the in situ split approach resulted in R0 liver resection in all our patients with primary liver cancer. The operation was technically feasible and it provided a better view and increased maneuverability in the cramped operative space compared with the traditional open/laparoscopic approach. The approach also better complies with the "no-touch" principle for malignant tumors. Its long-term oncological outcomes require further studies.

A review of conventional and newer generation microwave ablation systems for hepatocellular carcinoma

Although microwave ablation (MWA) exhibits a high thermal efficiency, the major limitation of conventional MWA systems is the lack of predictability of the ablation zone size and shape. Therefore, a specific newer generation MWA system, The Emprint™ Ablation System with Thermosphere™ Technology, was designed to create predictable large spherical zones of ablation that are not impacted by varying tissue environments. The time required for ablation with MWA systems is short, and the shape of the necrosis is elliptical with the older systems and spherical with the new system. In addition, because MWA has no heat-sink effect, it can be used to ablate tumors adjacent to major vessels. Although these factors yield a large ablation volume and result in good local control, excessive ablation of liver tissue and unexpected ablation of surrounding organs are possible. Therefore, MWA should be carefully performed. This review highlights the efficacy and complications of MWA performed with conventional systems and the newer generation system in patients with hepatocellular carcinoma (HCC). MWA with the newer generation system seems to be a promising treatment option for large HCCs and secondary hepatic malignancies, with several advantages over other available ablation techniques, including conventional MWA. However, further randomized controlled trials are necessary to fully clarify the benefits and pitfalls of this new system.

Hepatic resection versus operative microwave ablation for single hepatocellular carcinoma ≤5 cm: A propensity score-matched analysis

BACKGROUND

Little evidence exists regarding the perioperative and oncologic benefits of microwave ablation for hepatocellular carcinoma. The aim of this study was to compare the efficacy of hepatic resection and operative microwave ablation (microwave coagulo-necrotic therapy) for single hepatocellular carcinoma ≤5 cm.

METHODS

Between 1994 and 2015, a total of 551 patients with a single hepatocellular carcinoma ≤5 cm were treated in our institution (hepatic resection: n = 128; microwave coagulo-necrotic therapy: n = 423). We compared overall survival and recurrence-free survival between hepatic resection and microwave coagulo-necrotic therapy. Propensity score matching analysis identified 94 matched pairs of patients to compare outcomes.

RESULTS

After propensity score matching, baseline variables, including liver function and tumor size, were well-balanced between the 2 groups. The 5- and 10-year overall survival rates were 76% and 47% for hepatic resection and 77% and 48% for microwave coagulo-necrotic therapy, respectively (P = .865). The 5- and 10-year recurrence-free survival rates were 55% and 41% for hepatic resection and 47% and 32% for microwave coagulo-necrotic therapy, respectively (P = .377). In the subgroup analysis, the hepatic resection group had better recurrence-free survival than the microwave coagulo-necrotic therapy group in patients with tumor size >3 cm, with 5-year recurrence-free survival rates of 56.5% and 32.4% in the hepatic resection and microwave coagulo-necrotic therapy group, respectively (P = .029).

CONCLUSION

Our propensity score matching study confirmed no statistically significant differences in both overall survival and recurrence-free survival between hepatic resection and microwave coagulo-necrotic therapy for single hepatocellular carcinoma ≤5 cm; however, hepatic resection is recommended for hepatocellular carcinoma with tumor size >3 cm when patients have good liver function.

Microwave ablation compared with hepatic resection for the treatment of hepatocellular carcinoma and liver metastases: a systematic review and meta-analysis

Background

Hepatic resection (HR) is the gold standard liver cancer treatment, but few patients are eligible due to comorbidities or tumor location. Microwave ablation (MWA) is an important complementary liver cancer treatment to HR. This systematic review compared MWA with HR for liver cancer treatment.

Methods

A systematic search of MEDLINE, EMBASE, and CENTRAL was conducted for randomized and observational studies published from 2006 onwards. The primary outcome was local tumor recurrence (LTR), and a random effects model was used for meta-analyses.

Results

Of the 1845 studies identified, 1 randomized and 15 observational studies met the inclusion criteria. LTR was significantly increased with MWA versus HR (risk ratio (RR) = 2.49; P = 0.016). In secondary measures, HR provided significantly higher 3- and 5-year overall survival (RR = 0.94; P = 0.03 and RR = 0.88; P = 0.01, respectively) and 3-year disease-free survival (RR = 0.78; P = 0.009). MWA exhibited significantly shorter length of stay (weighted mean difference (WMD) = − 6.16 days; P < 0.001) and operative time (WMD = − 58.69 min; P < 0.001), less intraoperative blood loss (WMD = − 189.09 mL; P = 0.006), and fewer complications than HR (RR = 0.31; P < 0.001). When MWA was combined with HR and compared with either modality alone, complications and blood loss were significantly lower with the combination treatment; however, there were no differences in other outcomes. Subgroup and sensitivity analyses were generally aligned with the main results.

Conclusions

MWA can be an effective and safe alternative to HR in patients/tumors that are not amenable to resection. More randomized and economic studies should be performed that compare the two treatments, especially to determine the target population that benefits most from MWA.

Electronic supplementary material

The online version of this article (10.1186/s12957-019-1632-6) contains supplementary material, which is available to authorized users.

Current topics in liver surgery

Liver resection is one of the main treatment strategies for liver malignancies. Mortality and morbidity of liver surgery has improved significantly with progress in selection criteria, development of operative procedures and improvements in perioperative management. Safe liver resection has thus become more available worldwide. We have identified four current topics related to liver resection (anatomical liver resection, laparoscopic liver resection, staged liver resection and chemotherapy-induced liver injury). The balance between treatment effect and patient safety needs to be considered when planning liver resection. Progress in this area has been rapid thanks to the efforts of many surgeons, and outcomes have improved significantly as a result. These topics remain to be solved and more robust evidence is needed. Precise selection of the optimal procedure and risk evaluation should be standardized with further development of each topic. The present article reviews these four current topics with a focus on safety and efficacy in recent series.

Comparative efficacy of treatment strategies for hepatocellular carcinoma: systematic review and network meta-analysis

OBJECTIVE

Hepatocellular carcinoma (HCC) is the third leading cause of cancer death worldwide. We conducted network meta-regression within a Bayesian framework to compare and rank different treatment strategies for HCC through direct and indirect evidence from international studies.

METHODS AND ANALYSES

We pooled the OR for 1-year, 3-year and 5-year overall survival, based on lesions of size ˂ 3 cm, 3-5 cm and ≤5 cm, using five therapeutic options including resection (RES), radiofrequency ablation (RFA), microwave ablation (MWA), transcatheter arterial chemoembolisation (TACE) plus RFA (TR) and percutaneous ethanol injection (PEI).

RESULTS

We identified 74 studies, including 26 944 patients. After adjustment for study design, and in the full sample of studies, the treatments were ranked in order of greatest to least benefit as follows for 5 year survival: (1) RES, (2) TR, (3) RFA, (4) MWA and (5) PEI. The ranks were similar for 1- and 3-year survival, with RES and TR being the highest ranking treatments. In both smaller (<3 cm) and larger tumours (3-5 cm), RES and TR were also the two highest ranking treatments. There was little evidence of inconsistency between direct and indirect evidence.

CONCLUSION

The comparison of different treatment strategies for HCC indicated that RES is associated with longer survival. However, many of the between-treatment comparisons were not statistically significant and, for now, selection of strategies for treatment will depend on patient and disease characteristics. Additionally, much of the evidence was provided by non-randomised studies and knowledge gaps still exist. More head-to-head comparisons between both RES and TR, or other approaches, will be necessary to confirm these findings.

Meta-analysis of short- and long-term outcomes after pure laparoscopic versus open liver surgery in hepatocellular carcinoma patients

Background

The advantages of laparoscopy are widely known. Nevertheless, its legitimacy in liver surgery is often questioned because of the uncertain value associated with minimally invasive methods. Our main goal was to compare the outcomes of pure laparoscopic (LLR) and open liver resection (OLR) in patients with hepatocellular carcinoma.

Methods

We searched EMBASE, MEDLINE, Web of Science, and The Cochrane Library databases to find eligible studies. The most recent search was performed on December 1, 2017. Studies were regarded as suitable if they reported morbidity in patients undergoing LLR versus OLR. Extracted data were pooled and subsequently used in a meta-analysis with a random-effects model. Clinical applicability of results was evaluated using predictive intervals. Review was reported following the PRISMA guidelines.

Results

From 2085 articles, forty-three studies (N = 5100 patients) were included in the meta-analysis. Our findings showed that LLR had lower overall morbidity than OLR (15.59% vs. 29.88%, p < 0.001). Moreover, major morbidity was reduced in the LLR group (3.78% vs. 8.69%, p < 0.001). There were no differences between groups in terms of mortality (1.58% vs. 2.96%, p = 0.05) and both 3- and 5-year overall survival (68.97% vs. 68.12%, p = 0.41) and disease-free survival (46.57% vs. 44.84%, p = 0.46).

Conclusions

The meta-analysis showed that LLR is beneficial in terms of overall morbidity and non-procedure-specific complications. That being said, these results are based on non-randomized trials. For these reasons, we are calling for randomization in upcoming studies. Systematic review registration: PROSPERO registration number CRD42018084576.

Electronic supplementary material

The online version of this article (10.1007/s00464-018-6431-6) contains supplementary material, which is available to authorized users.

Meta-analysis of laparoscopic versus open liver resection for hepatocellular carcinoma

AIM

The aim of this study was to evaluate the surgical safety and effectiveness of laparoscopic hepatectomy (LH) in short- and long-term outcomes compared to open hepatectomy (OH) in patients treated for hepatocellular carcinoma (HCC).

METHODS

An electronic search of reports published before August 2017 was carried out to identify comparative studies evaluating LH versus OH for HCC.

RESULTS

A total of 5889 patients (2421 underwent LH; 3468 underwent OH) were included in our meta-analysis from 47 studies. Laparoscopic hepatectomies were associated with favorable outcomes in terms of operative blood loss (mean difference [MD], -147.27; 95% confidence interval [CI], -217.00, -77.55), blood transfusion requirement (odds ratio [OR], 0.51; 95% CI, 0.40, 0.65), pathologic resection margins (MD, 0.07; 95% CI, 0.02, 0.12; P = 0.01), R0 resection rate (OR, 1.34; 95% CI, 0.98, 1.84; P = 0.07), and length of hospital stay (MD, -5.13; 95% confidence interval, -6.23, -4.03). There were no differences between the groups in overall survival (OS) at 1 year (OR, 1.41; 95% CI, 1.00, 1.98), 3 years (OR, 1.12; 95% CI, 0.93, 1.36), or 5 years (OR, 1.18; 95% CI, 0.94, 1.46), in disease-free survival (DFS) at 1 (OR, 1.19; 95% CI, 0.94, 1.51), 3 years (OR, 1.07; 95% CI, 0.86, 1.33), or 5 years (OR, 1.13; 95% CI, 0.92, 1.40), or in recurrence (OR, 0.90; 95% CI, 0.74, 1.08).

CONCLUSION

Compared to OH, LH is superior in terms of lower intraoperative blood loss and the requirement for blood transfusion, larger pathologic resection margins, increased R0 resection rates, and shorter length of hospital stay. Laparoscopic hepatectomy and OH have similar OS, DFS, and recurrence.

Novel approaches for molecular targeted therapy against hepatocellular carcinoma

Systemic chemotherapy using a multitargeted tyrosine kinase inhibitor is an established treatment for advanced-stage tumors in various organs. Comprehensive genomic analyses using next-generation sequencing technology revealed the intra- and intertumor heterogeneity of human hepatocellular carcinomas (HCCs), and provided evidence for the use of therapeutic agents effective against multiple targets in tumor cells. Recently, the efficacy and safety of a multitargeted tyrosine kinase inhibitor, lenvatinib, was confirmed by a randomized global phase III trial; thus, lenvatinib was approved as first-line therapy for HCC, providing a new therapeutic option for patients at an advanced stage. In this article, we introduce the application of molecular targeted therapy using lenvatinib and discuss future aspects of therapeutic options for advanced HCC.

Open Liver Resection, Laparoscopic Liver Resection, and Percutaneous Thermal Ablation for Patients with Solitary Small Hepatocellular Carcinoma (≤30 mm): Review of the Literature and Proposal for a Therapeutic Strategy

BACKGROUND

Patients with a single hepatocellular carcinoma (HCC) ≤3 cm and preserved liver function have the highest likelihood to be cured if treated. The most adequate treatment methods are yet a matter that is debated.

METHODS

We reviewed the literature about open anatomic resection (AR), laparoscopic liver resection (LLR), and percutaneous thermal ablation (PTA).

RESULTS

PTA is effective as resection for HCC < 2 cm, when they are neither subcapsular nor perivascular. PTA in HCC of 2-3 cm is under evaluation. AR with the removal of the tumor-bearing portal territory is recommended for HCC > 2 cm, except for subcapsular ones. In comparison with open surgery, LRR has better short-term outcomes and non-inferior long-term outcomes. LLR is standardized for superficial limited resections and for left-sided AR.

CONCLUSIONS

According to the available evidences, the following therapeutic proposal can be advanced. Laparoscopic limited resection is the standard for any subcapsular HCC. PTA is the first-line treatment for deep-located HCC < 2 cm, except for those in contact with Glissonean pedicles. Laparoscopic AR is the standard for deep-located HCC of 2-3 cm of the left liver, while open AR is the standard for deep-located HCC of 2-3 cm in the right liver. HCC in contact with Glissonean pedicles should be scheduled for resection (open or laparoscopic) independent of their size. Liver transplantation is reserved to otherwise untreatable patients or as a salvage procedure at recurrence.

Comparison of microwave ablation and hepatic resection for hepatocellular carcinoma: a meta-analysis

BACKGROUND AND AIMS

Hepatic resection (HRN) and microwave ablation (MWA) have significant advantages in treating hepatocellular carcinoma; however, it remains unclear which way produces better outcomes. This meta-analysis of cohort studies compared the treatments in terms of effectiveness and safety.

METHODS

Six electronic databases (PubMed, Medline, EMBASE, Web of Science, EBSCO, and The Cochrane Library) were retrieved for studies comparing MWA and HRN. The meta-analysis was conducted based on statement of preferred reporting items for systematic reviews and meta-analyses.

RESULTS

Nine studies met the inclusion criteria, with a total of 1,480 patients. The overall meta-analysis demonstrated no significant difference in overall survival between the MWA group and the HRN group (HR =0.98, 95% CI =0.76-1.26, P=0.878). There was no difference in disease-free survival between the MWA group and the HRN group (HR =1.16, 95% CI =0.79-1.71, P=0.442). Meanwhile, the meta-analysis demonstrated that MWA was associated with shorter operation time (standardized mean difference [SMD] =-1.37, 95% CI =-1.92 to -0.81, P=0.000), less amount of blood loss in operation (SWD =-1.19, 95% CI =-1.76 to -0.61, P=0.000), and less complications (OR =0.22, 95% CI =0.12-0.40, P=0.000) than HRN.

CONCLUSION

In conclusion, our meta-analysis suggests that MWA may be superior to HRN as it is as effective as HRN in terms of overall survival, disease-free survival, tumor recurrence, and is associated with shorter operation time, less amount of blood loss, and fewer complications.

Is laparoscopic hepatectomy superior to open hepatectomy for hepatocellular carcinoma?

The low perioperative morbidity and shorter hospital stay associated with laparoscopic hepatectomy have made it an often-used option at many liver centers, despite the fact that many patients with hepatocellular carcinoma have cirrhosis, which makes the procedure more difficult and dangerous. Type of surgical procedure proves not to be a primary risk factor for poor outcomes after hepatic resection for hepatocellular carcinoma, the available evidence clearly shows that laparoscopic hepatectomy is an effective alternative to the open procedure for patients with early-stage hepatocellular carcinoma, even in the presence of cirrhosis. Whether the same is true for patients with intermediate or advanced disease is less clear, since laparoscopic major hepatectomy remains a technically demanding procedure.