Comparison of microwave ablation and radiofrequency ablation for hepatocellular carcinoma: a systematic review and meta-analysis

Background: Microwave ablation (MWA) has several advantages over radiofrequency ablation (RFA) for the treatment of hepatocellular carcinoma (HCC). We aimed to compare the efficacy and safety of MWA with those of RFA for HCC from the perspectives of percutaneous and laparoscopic approaches.

Methods: PubMed/MEDLINE, Embase, the Cochrane library, and China Biology Medicine databases were searched. Studies comparing the efficacy and safety of MWA with those of RFA in patients with HCC were considered eligible. Complete ablation (CA), local recurrence (LR), disease-free survival (DFS), overall survival (OS), and the major complication rate were compared between MWA and RFA.

Results: Four randomized controlled trials and 10 cohort studies were included. For percutaneous ablation, no significant difference was found between MWA and RFA regarding CA, LR, DFS, OS, and the major complication rate. A subgroup analysis of tumors measuring ≥3?cm revealed no difference in CA and LR for percutaneous ablation. For laparoscopic ablation, a significantly lower LR rate and a non-significant trend toward a higher major complication rate were observed for the MWA group (odds ratio [OR] 2.16, 95% confidence interval [CI] 1.16–4.02, p?=?.01 for LR; OR 0.21, 95% CI 0.04–1.03, p?=?.05 for major complication rate). CA, DFS, and OS were similar between the two groups.

Conclusions: Percutaneous (P)-MWA had similar therapeutic effects compared with P-RFA for HCC. Patients undergoing laparoscopic MWA had a lower LR rate; however, their major complication rate appeared to be higher. The superiority of MWA over RFA remains unclear and needs to be confirmed by high-quality evidence.     

Ultrasound-guided percutaneous microwave ablation vs. surgical resection for thoracoabdominal wall implants from hepatocellular carcinoma: intermediate-term results

Objective: The aims of this study were to compare the clinical outcomes between ultrasound (US)-guided percutaneous microwave ablation (MWA) and surgical resection (SR) in patients with thoracoabdominal wall implants from hepatocellular carcinom (HCC) and to identify the prognostic factors associated with the two treatment methods.

Materials and methods: A total of 47 patients (mean age, 56.7?±?15.9 years, range, 18–78 years; 34 men and 13 women) with 61 thoracoabdominal wall HCC seeding were included from April 2007 to May 2017. Twenty-five patients underwent US-guided MWA and 22 patients underwent SR. Survival, recurrence and liver function were compared between the two groups. Effect of changes in key parameters (i.e. overall survival (OS), disease-free survival (DFS) and local tumour reoccurrence-free (LTRF)) was statistically analysed with the log-rank test. Univariate and multivariate analyses were performed on several clinicopathological variables to identify factors affecting long-term outcome and recurrence.

Results: The OS, DFS and LTRF after MWA were comparable to those of SR (p?=0.493, p?=?0.578 and p?=0.270, respectively). Estimated 5-year overall survival rates were 63% after MWA and 48.1% after SR; for disease-free survival, estimated 5-year rates were 67.5% after MWA and 48.8% after SR; estimated 24-month LTRF rates were 71.3% after MWA and 87.8% after SR. The MWA group had less surgical time (p?=?<0.001), estimated blood loss (p =?<0.001) and post-operative hospitalisation (p?=?0.032) and cost (p?=?0.015). Multivariate analysis showed remnant intrahepatic tumour (p?=0.007), Child Pugh grade (p?=?0.009) and metastasis (p=?<0.001), were predictors for survival rate.

Conclusions: Ultrasound-guided percutaneous MWA is a safe and effective treatment method for metastatic HCC on the thoracoabdominal wall with similar outcomes to SR. Residual intrahepatic HCC, Child Pugh grade and distant metastasis are predictors for survival.     

Combining transarterial chemoembolization with radiofrequency ablation for hepatocellular carcinoma

The aim of this study was to compare the effectiveness of combination of radiofrequency ablation (RFA) and transarterial chemoembolization (TACE) with that of RFA alone in patients with hepatocellular carcinoma (HCC). All possible trials comparing RFA plus TACE with RFA alone for HCC were included into this meta-analysis. We estimated the summary odds ratio (OR) with its 95 % confidence interval (95 % CI) to assess the effects. Nineteen eligible studies matched the selection criteria, including 1,728 patients. Meta-analysis showed that the combination of TACE and RFA (OR_1 year?=?2.14, 95 % CI?=?1.57–2.91, P?<?0.001; OR_3 years?=?1.98, 95 % CI?=?1.28–3.07, P?=?0.001; OR_5 years?=?2.70, 95 % CI?=?1.42–5.14, P?=?0.003) were associated with higher survival rates. No evidence of publication bias was observed. High-quality evidence suggests that TACE plus RFA improve the survival rates compared with RFA alone for patients with HCC.     

Combined radiofrequency ablation and ethanol injection versus repeat hepatectomy for elderly patients with recurrent hepatocellular carcinoma after initial hepatic surgery

Purpose: To retrospectively compare the efficacy and safety of combined radiofrequency ablation and percutaneous ethanol injection (RFA–PEI) with repeat hepatectomy for elderly patients with initial recurrent hepatocellular carcinoma (HCC) after hepatic surgery.

Methods: From January 2009 to June 2015, 105 elderly patients (≥70?years) who underwent RFA–PEI (n?=?57) or repeated hepatectomy (n?=?48) for recurrent HCC?≤?5.0?cm were included in the study. The overall survival (OS) and recurrence-free survival (RFS) were analysed with the Kaplan–Meier method and compared by the log-rank test. Non-tumour-related death, complications and hospital stays were assessed. Univariate and multivariate analyses were performed to identify the prognostic significance of the variables in predicting the OS and RFS.

Results: OS rates were 78.2%, 40.8% and 36.7% at 1, 3 and 5?years after RFA–PEI and 76.3%, 52.5% and 42.6% after repeat hepatectomy, respectively (p?=?0.413). Correspondingly, the 1-, 3- and 5-year RFS rates after RFA–PEI and repeat hepatectomy were 69.5%, 37.8%, 33.1% and 73.1%, 49.7%, 40.7%, respectively (p?=?0.465). Non-tumour-related deaths in the RFA–PEI group (2/57) were significantly fewer than those in the repeat hepatectomy group (10/48) (p?=?0.016). RFA–PEI was superior to repeat hepatectomy regarding the major complication rates and length of in-hospital stay (both p?p?=?0.037) and RFS (HR?=?1.866, 95% CI?=?1.064–3.274, p?=?0.030).

Conclusion: RFA–PEI provides comparable OS and RFS to repeat hepatectomy for elderly patients with small recurrent HCC after hepatectomy but with fewer non-tumour-related deaths, major complications and shorter hospital stays.     

Higher Efficiency of Percutaneous Microwave (MWA) Than Radiofrequency Ablation (RFA) in Achieving Complete Response in Cirrhotic Patients with Early Hepatocellular Carcinoma

Background: Contrasting data are available in the literature regarding the superiority of percutaneous microwave ablation (MWA) or radiofrequency ablation (RFA) in very early or early (BCLA 0 or A) hepatocellular carcinoma (HCC). Aims: The primary outcome was to compare the efficacy of RFA and MWA in achieving complete response in cirrhotic patients with early and very early HCC. The secondary outcomes were to evaluate the overall survival and the recurrence rate. Methods: A retrospective, observational, single-center study was performed. Inclusion criteria were liver cirrhosis, new diagnosis of a single node of HCC measuring a maximum of 50 mm or up to three nodules with diameter up to 35 mm, treatment with RFA or MWA. Radiological response was evaluated with multiphasic contrast-enhanced Computed Tomography or Magnetic Resonance Imaging at 5–7 weeks after thermal ablation. Complete response was defined when no vital tissue was detected after treatment. Results: Overall, 251 HCC patients were included in this study; 81 patients were treated with MWA and 170 with RFA. The complete response rate was similar in MWA and RFA groups (out of 331 nodules, 87.5% (91/104) were treated with MWA and 84.2% (186/221) were treated with RFA, p = 0.504). Interestingly, a subanalysis demonstrated that for 21–35 mm nodules, the probability to achieve a complete response using MWA was almost 5 times higher than for RFA (OR = 4.88, 95% CI 1.37–17.31, p = 0.014). Moreover, recurrence rate in 21–35 mm nodules was higher with RFA with respect to MWA (31.9% versus 13.5%, p = 0.019). Overall survival was 80.4% (45/56) when treated with MWA and 62.2% (56/90) when treated with RFA (p = 0.027). No significant difference was observed between MWA and RFA treatment in the 15–20 mm nodules group. Conclusion: This study showed that MWA is more efficient than RFA in achieving complete response in HCC nodules with 21 to 35 mm diameter.     

Ablation therapy of non-colorectal cancer lung metastases: retrospective analysis of tumour response post-laser-induced interstitial thermotherapy (LITT), radiofrequency ablation (RFA) and microwave ablation (MWA)

Purpose: To retrospectively compare the local tumour response and survival rates in patients with non-colorectal cancer lung metastases post-ablation therapy using laser-induced thermotherapy (LITT), radiofrequency ablation (RFA) and microwave ablation (MWA).

Material and methods: Retrospective analysis of 175 computed tomography (CT)-guided ablation sessions performed on 109 patients (43 males and 66 females, mean age: 56.6 years). Seventeen patients with 22 lesions underwent LITT treatment (tumour size: 1.2–4.8?cm), 29 patients with 49 lesions underwent RFA (tumour size: 0.8–4.5?cm) and 63 patients with 104 lesions underwent MWA treatment (tumour size: 0.6–5?cm). CT scans were performed 24-h post-therapy and on follow-up at 3, 6, 12, 18 and 24 months.

Results: The overall-survival rates at 1-, 2-, 3- and 4-year were 93.8, 56.3, 50.0 and 31.3% for patients treated with LITT; 81.5, 50.0, 45.5 and 24.2% for patients treated with RFA and 97.6, 79.9, 62.3 and 45.4% for patients treated with MWA, respectively. The mean survival time was 34.14 months for MWA, 34.79 months for RFA and 35.32 months for LITT. In paired comparison, a significant difference could be detected between MWA versus RFA (p?=?0.032). The progression-free survival showed a median of 23.49?±?0.62 months for MWA,19.88?±?2.17 months for LITT and 16.66?±?0.66 months for RFA (p?=?0.048). The lowest recurrence rate was detected in lesions ablated with MWA (7.7%; 8 of 104 lesions) followed by RFA (20.4%; 10 of 49 lesions) and LITT (27.3%; 6 of 22 lesions) p value of 0.012. Pneumothorax was detected in 22.16% of MWA ablations, 22.73% of LITT ablations and 14.23% of RFA ablations.

Conclusion: LITT, RFA and MWA may provide an effective therapeutic option for non-colorectal cancer lung metastases with an advantage for MWA regarding local tumour control and progression-free survival rate.     

Radiofrequency ablation versus surgical resection for hepatocellular carcinoma within the Milan criteria: A study of 281 Western patients

Abstract

Objectives: The aim of this study was to compare survival between radiofrequency ablation (RFA) and surgical resection (SR) in patients with hepatocellular carcinoma (HCC) within Milan criteria. Methods: From January 2004 to December 2013 we consecutively and retrospectively included all patients with first occurrence of HCC within Milan criteria receiving SR or RFA as first-line treatment. The cumulative overall survival (OS) and disease-free survival (DFS) were compared after inverse probability weighting (including confounding factor). Results: A total of 281 patients (RFA 178, SR 103) were enrolled. In multivariate Cox regression RFA and SR were not independent predictors of survival or recurrence. The respective weighted 5 years OS and DFS for patients with propensity scores between 0.1–0.9 in the SR and RFA groups were 54–33% and 60–16.9%, P?=?0.695 and P?=?0.426, respectively. Local tumour progression rate did not differ according to treatment (P?=?0.523). Major complication rate was higher in the SR group, P?=?0.001. Hospitalisation duration was lower in the RFA group (mean 2.19 days, range 2–7) than in the SR group (mean 10.2 days, range 3–30), P?<?0.001. Conclusion: This large Western study has shown that OS and DFS did not differ after RFA (using mainly multipolar devices) and SR, for HCC within the Milan criteria in a European population, with a shorter hospitalisation time and a lower complication rate for RFA.     

Hepatocellular carcinoma abutting large vessels: comparison of four percutaneous ablation systems

Purpose: To compare overall local tumour progression (OLTP), defined as the failure of primary ablation or local tumour progression, with single applicator monopolar radiofrequency ablation (RFA), microwave ablation (MWA), cluster-RFA and multi-bipolar radiofrequency (mbpRFA) in the treatment of hepatocellular carcinoma (HCC)?≤?5?cm abutting large vessels (≥3?mm).

Materials and methods: This multicenter, retrospective, per-nodule study was performed from 2007 to 2015. The study was approved by the ethics review board, and informed consent was waived. A total of 160/914 HCC nodules treated by thermal ablation and abutting large vessels (40 per treatment group) treated by monopolar RFA, MWA, cluster-RFA or mbpRFA were matched for tumour size, alpha-feto-protein level and vessel size. OLTP rates were compared by the log-rank test and the multivariate Cox model after matching.

Results: No differences were observed in tumour size, vessel size or alpha-feto-protein levels among the three groups (p?=?1). The cumulative 4-year OLTP rates following monopolar RFA, cluster-RFA, multi-bipolar RFA and MWA were 50.5%, 16.3%, 16.3% and 44.2%, respectively (p?=?0.036). On multivariate Cox regression, vessel size ≥10?mm, monopolar RFA and MWA were independent risk factors of OLTP compared to cluster-RFA or mbpRFA.

Conclusion: Multi-applicator RFA provides better local tumour control in HCC abutting large vessels than single-applicator techniques (monopolar RFA or MWA).     

Radiofrequency ablation or microwave ablation combined with transcatheter arterial chemoembolization in treatment of hepatocellular carcinoma by comparing with radiofrequency ablation alone简

Objective：To compare radiofrequency ablation （RFA） or microwave ablation （MWA） and transcatheter arterial chemoembolization （TACE） with RFA or MWA monotherapy in hepatocellular carcinoma （HCC）.Methods：A prospective,randomized,controlled trial was conducted on 94 patients with HCC ≤7 cm at a single tertiary referral center from June 2008 to June 2010 at the Department of Hepatobiliary Surgery,the Second Affiliated Hospital of Southeast University.The patients were randomly assigned into the TACERFA or TACE-MWA （combined treatment group） and the RFA-alone or MWA-alone groups （control group）.The primary end point was overall survival.The secondary end point was recurrence-free survival,and the tertiary end point was adverse effects.Results：Until the time of censor,17 patients in the TACE-RFA or TACE-MWA group had died.The median follow-up time of the patients who were still alive for the TACE-RFA or TACE-MWA group was 47.5±11.3 months （range,29 to 62 months）.The 1-,3-and 5-year overall survival for the TACE-RFA or TACE-MWA group was 93.6％,68.1％ and 61.7％,respectively.Twenty-five patients in the RFA or MWA group had died.The median follow-up time of the patients who were still alive for the RFA or MWA group was 47.0±12.9 months （range,28 to 62 months）.The 1-,3-and 5-year overall survival for the RFA or MWA group was 85.1％,59.6％ and 44.7％,respectively.The patients in the TACE-RFA or TACE-MWA group had better overall survival than the RFA or MWA group [hazard ratio （HR）,0.526; 95％ confidence interval （95％ CO,0.334-0.823; P=0.002],and showed better recurrence-free survival than the RFA or MWA group （HR,0.582; 95％ CI,0.368-0.895; P=0.008）.Conclusions：RFA or MWA combined with TACE in the treatment of HCC ≤7 cm was superior to RFA or MWA alone in improving survival by reducing arterial and portal blood flow due to TACE with iodized oil before RFA.     

The efficacy and safety of microwave ablation in patients with retroperitoneal metastases

Background: Retroperitoneal metastases are common, and most present with symptoms; however, treatments for this condition are limited. This retrospective study verified the efficacy and safety of microwave ablation (MWA) in retroperitoneal metastases patients.

Methods: Patients with pathologically confirmed malignant carcinoma and imaging showing retroperitoneal metastases were enrolled and underwent MWA. The end-points included objective response rate, time to local progression (TTLP), overall survival, visual analogue scale (VAS) score, dose of morphine pre- and post-ablation and complications.

Results: Twenty-three patients were enrolled. The mean tumour diameter was 3.6?cm. Altogether, 29 tumour sites in 23 patients were ablated during 23 procedures; technical success was achieved in all 23 patients. The objective response and disease control rates were 95.7% and 100.0%, respectively. The mean TTLP and median OS were 22.8?months (95% CI: 16.1–29.6?months) and 10.6?months (95% CI: 7.4–13.8?months), respectively. In 13 patients with symptoms, the VAS values before ablation and 48?h, 1?month, 2?months, 3?months and 6?months after ablation were 5.38, 2.77 (p?=?0.015), 2.15 (p?=?0.001), 2.17 (p?=?0.001), 1.40 (p?=?0.000) and 1.71 (p?=?0.006), respectively. The corresponding morphine doses were 76.9?mg, 70.7?mg (p?=?0.584), 50.7?mg (p?=?0.031), 55.0?mg (p?=?0.097), 46.0?mg (p?=?0.057) and 40.0?mg (p?=?0.363), respectively. No ablation-associated mortality was observed. Major complications, minor complications and adverse events were observed in eight (34.8%), five (21.7%) and four (17.4%) patients, respectively.

Conclusion: MWA for the treatment of retroperitoneal metastases was effective and the complications were common.     

Trans-arterial chemoembolization + radiofrequency ablation versus surgical resection in hepatocellular carcinoma – A meta-analysis

BackgroundHepatocellular Carcinoma (HCC) remains the third most common cause of cancer death worldwide, with countries in Asia being affected the most. The mainstay of curative therapy for early HCC is radiofrequency ablation (RFA) or surgery; either surgical resection (SR) or liver transplantation. Latest evidence however suggests that combination of TACE+ RFA may provide outcomes comparable to SR.AimTo compare oncologic outcomes and safety profile of TACE + RFA to SR alone in HCC.Materials and methodsA systematic review was conducted through Pubmed, EMBASE and Cochrane Library for literature published before April 2019. Outcomes measured were disease-free survival(DFS), overall survival(OS) and major complications. DFS was further divided into local tumour progression(LTP), intrahepatic distant recurrence(IDR) and distant metastasis(DM).ResultsEight retrospective studies and one randomized controlled trial, involving 1892 patients met eligibility criteria and were included. Unadjusted pooled analysis demonstrated no significant difference in 1-year, 3-year and 5-year OS and 1-year DFS between TACE+RFA and SR. SR had superior 3-year DFS (OR 0.78, 95% CI 0.62–0.98, p = 0.03) and 5-year DFS (OR 0.74, 95% CI 0.58–0.95, p = 0.02) compared to TACE+RFA. When analysing only the propensity matched data, the difference in 3-year DFS and 5-year DFS was not significant. TACE+RFA had a higher LTP rate (OR 2.48, 95% CI 1.05–5.86, p = 0.04) compared to SR but IDR and DM rates were not significant.Discussion and conclusionTACE+RFA offer comparable oncologic outcomes in patients with HCC as compared with SR and with added benefit of lower morbidity.     

Microwave ablation is effective against liver metastases from gastric adenocarcinoma

Purpose: The resection rate for liver metastases from gastric cancer is only 1.4–21.1%. This study aimed to evaluate the safety and therapeutic efficacy of microwave ablation (MWA) for liver metastases from gastric adenocarcinoma (LMGC).

Materials and methods: A database of 108 gastric adenocarcinoma patients with liver metastases who underwent MWA (n?=?32) or systemic chemotherapy (n?=?76) for LMGC between 2008 and 2016 was reviewed. Overall survival curves were assessed and compared based on different therapies.

Results: All the patients were followed up for a median of 15?months (range, 2–68?months). The median cumulative survival times of patients after MWA and systemic chemotherapy were 25 (95% confidence interval (CI) 16.5–33.5) months and 12 (95% CI 7.7–16.3) months, respectively (HR 1.751, 95% CI 1.077–2.845; p?=?.015). The 1-, 3-, and 5- year survival rates were 80.9%, 31.2%, and 16.7% (MWA group); and 50.0%, 18.8%, and 5.4% (chemotherapy group), respectively. In the MWA group, side effects were reported in eight patients who developed abdominal pain, transient fever, or nausea. Dominant size, number of liver metastases, therapeutic modalities, and presence of extrahepatic metastases showed significant prognostic value in univariate analyses; while the latter three were identified as independent prognostic factors in multivariate regression analysis.

Conclusions: MWA is a safe and useful alternative for liver metastases from gastric adenocarcinoma in selected patients.     

Percutaneous CT-guided radiofrequency ablation for unresectable hepatocellular carcinoma pulmonary metastases

Purpose: This study aimed to evaluate the safety and efficacy of percutaneous CT-guided radiofrequency ablation (RFA) for unresectable hepatocellular carcinoma pulmonary metastases (HCCPM) and to identify the prognostic factors for survival.

Materials and methods: We reviewed the medical records of 320 patients with HCCPM treated between January 2005 and January 2012. Among them, 29 patients with 68 lesions of unresectable HCCPM underwent 56 RFA sessions. Safety, local efficacy, survival and prognostic factors were evaluated. Survival was analysed using the Kaplan-Meier method. Univariate analyses were evaluated by the log-rank test.

Results: Pneumothorax requiring chest tube placement occurred in five (8.9%, 5/56) RFA sessions. During the median follow-up period of 23 months (range 6–70), 18 patients (62.1%, 18/29) died of tumour progression and 11 (37.9%, 11/29) were alive. The 1-, 2- and 3-year overall survival rates were 73.4%, 41.1% and 30%, respectively. The median progression-free survival was 18 months (95% confidence interval (CI) 9.8–26.2) and the median overall survival time was 21 months (95%CI, 9.7–32.3). The maximum tumour diameter ≤3?cm (p?=?0.002), the number of pulmonary metastases ≤3 (p?=?0.014), serum AFP level ≤400?ng/mL (p?=?0.003), and the controlled status of intrahepatic tumour after lung RFA (p?=?0.001) were favourable prognostic factors for overall survival.

Conclusions: Our study indicates that percutaneous CT-guided RFA, as an alternative treatment procedure to pulmonary metastasectomy, can be a safe and effective therapeutic option for unresectable HCCPM.     

Microwave ablation is as effective as radiofrequency ablation for very-early-stage hepatocellular carcinoma

Background: Percutaneous radiofrequency ablation (RFA) is a first-line treatment for very-early-stage hepatocellular carcinoma (HCC), whereas the efficacy of percutaneous microwave ablation (MWA) for very-early-stage HCC remains unclear. The purpose of this study was to clarify this issue by comparing the safety and efficacy of percutaneous MWA with percutaneous RFA in treating very-early-stage HCC. Methods: Clinical data of 460 patients who were diagnosed with very-early-stage HCC and treated with percutane-ous MWA or RFA between January 2007 and July 2012 at the Eastern Hepatobiliary Surgery Hospital, The Second Mili-tary Medical University, in Shanghai, China were retrospectively analyzed. Of these 460 patients, 159 received RFA, 301 received MWA. Overall survival (OS), recurrence-free survival (RFS), local tumor progression (LTP), complete ablation, and complication occurrence rates were compared between the two groups, and the prognostic factors associated with survival were analyzed. Results: No significant differences were observed between the two groups in terms of the 1-, 3-, or 5-year OS rates (99.3%, 90.4%, and 78.3% for MWA vs. 98.7%, 86.8%, and 73.3% for RFA, respectively;P= 0.331). Furthermore, no signif-icant differences were observed between the two groups in terms of the corresponding RFS rates (94.4%, 71.8%, and 46.9% for MWA vs. 89.9%, 67.3%, and 54.9% for RFA, respectively;P= 0.309), the LTP rates (9.6% vs. 10.1%,P= 0.883), the complete ablation rates (98.3% vs. 98.1%,P= 0.860), or the occurrence rates of major complications (0.7% vs. 0.6%,P= 0.691). By multivariate analysis, LTP, antiviral therapy, and treatment of recurrence were independent risk fac-tors for OS (P < 0.001), and the alpha-fetoprotein level was an independent prognostic factor for RFS (P= 0.002). Conclusions: MWA is as safe and effective as RFA in treating very-early-stage HCC, supporting MWA as a first-line treatment option for this disease.     

Percutaneous CT-guided thermal ablation as salvage therapy for recurrent non-small cell lung cancer after external beam radiotherapy: A retrospective study

Purpose: The aim of this study was to evaluate radiofrequency ablation (RFA) and microwave ablation (MWA) as a viable salvage option for patients with locally recurrent non-small cell lung cancer (NSCLC) after radiotherapy. Materials and methods: This retrospective study was conducted on patients who had received thermal ablation for recurrent NSCLC post-curative radiotherapy. Medical records and follow-up imaging with computed tomography (CT) and PET-CT were analysed to determine time to local progression (TTLP) and overall survival (OS). TTLP was determined according to the modified RECIST criteria. Results: Twelve patients, mean age 71?±?7 years, received 17 thermal ablation sessions, with RFA performed for four lesions and MWA for 13. Nine tumours were squamous cell cancers (SCC) and eight were adenocarcinomas. Eleven tumours had recurred post-external beam radiation and one post-stereotactic body radiation therapy. Mean tumour size was 34.2?±?12.8?mm, tumour stages prior to radiotherapy were Ia (2), Ib (3), IIa (4), IIb (1) and III (2). Follow-up period was 19?±?11 months. Overall median TTLP was 14 months (95% CI: 8, 19), and median OS was 35 months (95% CI: 12, 58). Mean TTLP for tumours <30?mm was 23 months and for tumours >30?mm 14 months (p?=?0.20). Recurrence rates reduced from 50% after initial ablation to 20% with a second ablation. Complication rate for pneumothorax requiring intervention was 17%. Conclusion: Both RFA and MWA ablation prolonged local tumour control with minimal morbidity in this study group of recurrent NSCLC after radiotherapy.     

Safety of radiofrequency ablation of benign thyroid nodules and recurrent thyroid cancers: a systematic review and meta-analysis

Abstract

Objective: We performed a systematic review and meta-analysis to evaluate the safety of radiofrequency ablation (RFA) for the treatment of benign thyroid nodules and recurrent thyroid cancers.

Materials and methods: Ovid-MEDLINE, EMBASE, and Library of Cochrane databases were searched up to 12 July 2016 for studies on the safety of RFA for treating benign thyroid nodules or recurrent thyroid cancers. Pooled proportions of overall and major complications were assessed using random-effects modelling. Heterogeneity among studies was determined using the χ² statistic for the pooled estimates and the inconsistency index I².

Results: A total of 24 eligible studies were included, giving a sample size of 2421 patients and 2786 thyroid nodules. 41 major complications and 48 minor complications of RFA were reported, giving a pooled proportion of 2.38% for overall RFA complications [95% confidence interval (CI): 1.42%–3.34%] and 1.35% for major RFA complications (95% CI: 0.89%–1.81%). There were no heterogeneities in either overall or major complications (I²?=?1.24%–21.79%). On subgroup analysis, the overall and major complication rates were significantly higher for malignant thyroid nodules than for benign thyroid nodules (p?=?0.0011 and 0.0038, respectively).

Conclusions: RFA was found to be safe for the treatment of benign thyroid nodules and recurrent thyroid cancers.     

Variables associated with vaginal discharge after ultrasound-guided percutaneous microwave ablation for adenomyosis

Objective The aim of this study was to analyse the significant variables for vaginal discharge after ultrasound-guided percutaneous microwave ablation (PMWA) therapy.

Materials and methods PMWA was performed on 117 patients with adenomyosis from October 2012 to July 2014. The presence or absence, colour, quantity and duration of vaginal discharge, which was different from pre-ablation, were recorded within 1 year after PMWA. Patients were categorised into G1 (n?=?26, without vaginal discharge), G2 (n?=?40, vaginal discharge lasting 1 to 19 days), and G3 (n?=?51, vaginal discharge lasting ≥20 days) groups. The potentially correlative variables were analysed. Variables with significant correlations with vaginal discharge post-ablation were identified via binary logistic regression analysis.

Results The differences in adenomyosis type, pre-ablation uterine volume, total microwave ablation energy, total non-perfused volume (NPV) and minimum distance from the non-perfused lesion (NPL) margin to the endomyometrial junction (EMJ) among groups were statistically significant (p?=?0.005, p?=?0.000, p?=?0.000, p?=?0.005 and p?=?0.000, respectively). Minimum distance from the NPL margin to the EMJ was the strongest predictor of vaginal discharge post-ablation with odds ratio (OR) 0.632, p?=?0.018, 95% CI 0.432–0.923. Patients with diffuse adenomyosis were more likely to have prolonged vaginal discharge (≥20 days) post-ablation (OR 3.461, p?=?0.000, 95% CI 1.759–7.536).

Conclusion The minimum distance from the NPL margin to the EMJ and adenomyosis type were significantly associated with vaginal discharge post-ablation.     

Needle track seeding after percutaneous radiofrequency ablation of hepatocellular carcinoma: 14-year experience at a single centre

Purpose: To determine the incidence, risk factors and prognosis associated with needle track seeding after percutaneous radiofrequency ablations (RFA) for hepatocellular carcinoma (HCC) with a long-term follow-up.

Materials and methods: A total of 741 HCC patients undergoing percutaneous RFA were retrospectively analysed. Mean follow-up interval was 34.3?±?26.8 months. All seeding neoplasms were diagnosed by imaging modalities with or without pathological evaluation. Risk factors, including Child–Pugh grading, tumour size, number, location, serum alpha-fetoprotein (AFP) level, track number, biopsy before RFA and electrode type were performed by univariate analysis. Further therapy and survival of seeding after RFA were assessed. Survival analysis was analysed by Kaplan–Meier method.

Results: Twelve patients (12 tumours) were diagnosed as seeding. It corresponds to an incidence of 1.6% (12/741) per patient and 0.9% (12/1341) per tumour. Seeding developed an average of 14.0?±?8.1 months (6–33 months). Significant risk factors included tumour >3?cm (p?=?0.031), subcapsular tumour (p?=?0.031), biopsy before RFA (p?=?0.001) and non-cool-tip electrode (p?=?0.034). Eight patients received local therapy and four cases only received systematic therapy for uncontrolled advanced hepatic tumour or distal metastasis. Of eight patients receiving local therapy, one patient had local recurrence 16 months later and other seven patients did not have local recurrence for 3–73 months. The cumulative survival rates after seeding were 55.6%, 27.8%, 9.3% at 1, 3 and 5 years, respectively.

Conclusion: Needle track seeding is a rare delayed complication after percutaneous RFA. Tumour >3?cm, subcapsular tumour, biopsy before RFA and non-cool-tip electrode are potential risk factors for seeding. Local therapies are effective methods for seeding patients.     

The local efficacy and influencing factors of ultrasound-guided percutaneous microwave ablation in colorectal liver metastases: a review of a 4-year experience at a single center

Purpose: To investigate the clinical effectiveness and safety of ultrasound (US)-guided percutaneous microwave ablation (MWA) for colorectal liver metastasis (CRLM) and evaluate the influencing factors of local efficacy.

Methods: From January 2013 to January 2017, 137 CRLM patients accepting US-guided percutaneous MWA were included. The 2450-MHz microwave ablation system and a cooled-shaft antenna were used. All patients were regularly followed up for at least 6?months. Technical success, complete ablation, local tumor progression (LTP), complications and side effects were assessed. Logistic regression analysis was used to identify the independent prognostic factors for LTP.

Results: In total, 411 lesions (mean diameter 15.4?±?7.2?mm, range 5–67?mm) were treated. Complete ablation was achieved in 99.27% (408/411) of lesions and 97.81% (134/137) of patients. LTP occurred in 5.35% (22/411) of lesions and 16.06% (22/137) of patients. LTP was more likely to occur in lesions larger than 3?cm in diameter (OR: 14.71; p?<?.001; 95% CI: 3.7 3–57.92), near a large vascular structure (OR: 7.04; p?<?.001; 95% CI: 2.41–20.60), near the diaphragm (OR: 4.02; p?=?.049; 95% CI: 1.05–16.11) and in patients with no response to chemotherapy before MWA (OR: 3.25; p?=?.032; 95% CI: 1.14–15.30). MWA was well tolerated, with a major complication rate of 3.65%, a minor complication rate of 8.03% and a mortality rate of 0%. Fever and pain were the most common side effects after MWA.

Conclusions: US-guided percutaneous MWA of CRLM is a safe and effective method that is expected to become a routine treatment for local tumor control of CRLM.     

Clinical and survival outcomes of percutaneous microwave ablation for intrahepatic cholangiocarcinoma

Objective: To evaluate the outcomes of percutaneous microwave ablation (MWA) and explore the prognostic factors for the survival of patients with intrahepatic cholangiocarcinoma (ICC).

Methods: A total of 107 patients (age: mean 58.0?years, range 15–85?years) with 171 ICCs (maximum size ≤5?cm, tumour number per patient ≤3) who underwent MWA for ICC during January 2009 to February 2016 were selected, and their clinical and pathological data were collected and reviewed. The MWA-associated mortality, major complication rate and survival were evaluated. The prognostic factors for survival in patients with ICC were analysed with univariate and multivariate analyses.

Results: The median follow-up after MWA was 20.1?months (2.8–63.5?months). There was no procedure-associated death. The overall procedure-associated major complication rate was 2.8%. The median PFS after MWA was 8.9?months; PFS rates after 6, 12, 18 and 24?months were 67.4%, 41.5%, 18.2% and 8.7%. The median OS was 28.0?months; OS rates after 1, 3 and 5?years were 93.5%, 39.6% and 7.9%. Child-Pugh class A and less tumour number were identified as factors predictive of prolonged PFS (HR for Child–Pugh class: 2.62, p?=?0.001; HR for tumour number: 2.07, p?=?0.002) and OS (HR for Child–Pugh class: 4.14, p?p?=?0.024).

Conclusions: Percutaneous ultrasound-guided MWA is safe and effective for ICC. Child–Pugh class A and less tumour number predict prolonged PFS and OS in patients with ICC treated by MWA.