US-guided Percutaneous Microwave Ablation Research Articles

Perfluorobutane application value in microwave ablation of Small Hepatocellular Carcinoma (

No studies have been retrieved comparing perfluorobutane with sulfur hexafluoride for microwave ablation (MWA) in small hepatocellular carcinoma(sHCC). To retrospective investigate the value of perfluorobutane ultrasonography contrast agent in ultrasonography (US)-guided MWA of sHCC. We conducted a retrospective clinical controlled study about US-guided percutaneous MWA in patients with sHCC, and in patients undergoing intra-operative treatment with perfluorobutane or sulfur hexafluoride. In both groups, a contrast agent was injected to clear the tumor and then a needle was inserted. A 5-point needle prick difficulty score was developed to compare needle prick difficulty in the two groups of cases. A total of 67 patients were included: 25 patients in group perfluorobutane, aged 41-82 (60.64±9.46), tumor size 1.1-2.8 (1.78±0.45) cm. 42 patients in group sulfur hexafluoride, aged 38-78 (62.26±9.27), with tumor size of 1.1-3.0 (1.89±0.49) cm. There was no significant difference in age or tumor size in both groups (P > 0.05). Puncture difficulty score (5-point): 2.0-2.7 (2.28±0.29) in group perfluorobutane, and 2.0-4.7 (2.95±0.85) in group sulfur hexafluoride, and the difference between the two groups was statistically significant (P < 0.05). Enhanced imaging results within 3 months after surgery: complete ablation rate was 100% (25/25) in the group perfluorobutane, 95.2% (40/42 in the group sulfur hexafluoride), with no significant difference between the two groups (P > 0.05). Perfluorobutane kupffer phase can make the operator accurately deploy the ablation needle and reduce the difficulty of operation.

Ultrasound-guided percutaneous microwave ablation for adenomyosis with abnormal uterine bleeding: clinical outcome and associated factors

Objective To investigate the factors affecting the efficacy of ultrasound (US)-guided percutaneous microwave ablation (PMWA) for adenomyosis with abnormal uterine bleeding (AUB-A). Methods Baseline data of patients with AUB-A who underwent US-guided PMWA treatment between October 2020 and October 2021, including demography characteristics, laboratory and imaging examination results were retrospectively analyzed. 3D reconstruction of magnetic resonance imaging (MRI) was applied to quantitatively assess the local treatment responses, including ratio of non-perfusion volume to adenomyosis volume (NPVr), ablation rate of the endometrial-myometrial junction (EMJ), and surface area (SA) of the ablated part of the EMJ. Patients were followed up at 3, 6, and 12 months after treatment, and divided into two groups: group with complete relief (CR), and group with partial relief (PR) or no relief (NR). Data were compared between them. Results Thirty-one patients were analyzed with a mean age of 38.7 ± 6.8 years (range: 24–48): 48.4% (15/31), 63.3% (19/30), and 65.5% (19/29) achieved CR at 3, 6, and 12 months, respectively. In univariate analysis, compared with the PR/NR group, serum CA125 levels were significantly lower in CR group at 3 months, while ablation rates of EMJ and SA of the ablated part of the EMJ were significantly higher at the three time points. Other baseline characteristics and NPVr did not differ between the two groups. Conclusion Baseline CA125 and ablation rate of the EMJ and SA of the ablated part of the EMJ are associated with the outcome of AUB-A patients after US-guided PMWA treatment.

A prognostic nomogram for intrahepatic progression-free survival in patients with colorectal liver metastases after ultrasound-guided percutaneous microwave ablation

Purpose The present study identified predictors of intrahepatic progression-free survival (ihPFS) after ultrasound (US)-guided percutaneous microwave ablation (MWA) for colorectal liver metastases (CRLMs) and developed a nomogram to predict ihPFS. Methods From January 2013 to December 2018, a total of 314 patients (224 men and 90 women; mean age, 57.1 ± 11.8 years; range, 23–86 years) with 645 CRLMs (mean diameter, 16.6 ± 6.5 mm; range, 6.0–45.0 mm) treated with US-guided percutaneous MWA were included and analyzed. The average number of CRLMs per patient treated was 2 (range, 1–8). A nomogram to predict ihPFS was developed based on a multivariable Cox model. Validation of the nomogram was performed using the concordance index (C-index), calibration curves, and decision curve analyses. Results The 1-, 2-, and 3-year cumulative ihPFS rates were 59.0%, 38.9%, and 30.8%, respectively. Maximal CRLM size, number of CRLMs, ablative margin, primary tumor lymph node status, and chemotherapy were five independent prognostic factors for ihPFS. The C-index of the nomogram was 0.702 (CI: 0.681–0.723). A risk classification system that perfectly classified the patients into three risk groups was constructed. The median ihPFS of patients in the low-, intermediate-, and high-risk groups was 36.3 months (95% CI: 21.4–51.1), 13.4 months (95% CI: 12.1–14.6), and 3.8 months (95% CI: 2.3–5.3), respectively. Conclusion The nomogram and risk classification system will facilitate the personalized assessment of ihPFS for patients receiving US-guided percutaneous MWA for CRLMs.

Role of Sonazoid-based contrast-enhanced ultrasonography in the microwave ablation of primary hyperparathyroidism

Objectives This study aimed to determine the performance of Sonazoid-based contrast-enhanced ultrasound (CEUS) in the microwave ablation (MWA) of primary hyperparathyroidism (pHPT). Methods Forty patients with pHPT were enrolled and treated with percutaneous ultrasound (US)-guided MWA assisted by CEUS. All patients underwent immediate CEUS examinations following MWA. On post-ablation day 1, patients who did not display a decrease in intact parathyroid hormone (iPTH) levels to the norm were examined by CEUS to evaluate an incomplete ablation. We compared the serum iPTH and calcium levels and the nodule volumes before and after MWA. The complications were evaluated during and after treatment. Results Immediately following MWA, CEUS demonstrated complete ablation with all 44 parathyroid nodules. On post-ablation day 1, five nodules in five patients displayed annular enhancement around the ablation zone on CEUS. The average maximum diameters of the nodules and the ablation zone were 1.09 ± 0.28 cm and 1.36 ± 0.23 cm, respectively. An ablation zone larger than the primary lesion (p < 0.05) generated a higher rate of complete ablation. Compared with pre-MWA, serum iPTH and calcium levels were significantly improved. Treatment success was achieved in 38 patients (95%). Hoarseness was a major complication in six patients (15%); however, it improved spontaneously within 1–4 months. We observed two recurrences (2/40, 5%) at 9 months and 11 months following MWA, respectively. Conclusion US-guided percutaneous MWA assisted by CEUS for pHPT is an effective and safe therapy. CEUS can avoid operative failure and improve the cure rate.

Comparison of percutaneous microwave ablation and surgical resection for hepatocellular carcinoma in the caudate lobe.

This study aims to compare the clinical efficacy and safety between ultrasound (US)-guided percutaneous microwave ablation (MWA) assisted with a three-dimensional (3D) visualization preoperative planning system and surgical resection (SR) for hepatocellular carcinoma (HCC) in the caudate lobe. Forty-nine patients diagnosed with caudate lobe HCC, who underwent US-guided percutaneous MWA (29 patients) or SR (20 patients), were enrolled between November 2005 and December 2018. Follow-up was performed at 1, 3, 6, 12, 18, 24, and 36 months after ablation or resection. The follow-up endpoint was recurrence or patient death. Overall survival (OS) and progression-free survival (PFS) were the primary outcomes, whereas local tumor progression (LTP), intrahepatic recurrence, and extrahepatic metastasis were the secondary ones. The mean age of the two groups was 61.4 ± 9.1 (MWA) and 53.1 ± 6.8 (SR), respectively, with a significant difference (P < 0.01). There were no significant differences in OS (69.0% in the MWA group and 75.0% in the SR group) and PFS (62.1% in the MWA group and 35.3% in the SR group). LTP, intrahepatic recurrence, and extrahepatic recurrence were 6.9% (2/29), 31.0% (9/29), and 20.7% (6/29) in the MWA group and 5.0% (1/20), 60.0% (12/20), and 5.0% (1/20) in the SR group. The MWA group was more cost-effective and required less hospitalization time. No major complications were observed. US-guided percutaneous MWA for HCC in the caudate lobe assisted with a 3D visualization preoperative planning system is an optional treatment with less expenses and shorter hospitalization than SR.

Ultrasound-guided percutaneous microwave ablation of bilateral renal cell carcinomas: Focus upon safety and efficacy.

To retrospectively review the safety and efficacy of ultrasound (US)-guided percutaneous microwave ablation (MWA) of bilateral renal cell carcinomas (BRCCs). In this study, eight patients of BRCCs with 20 lesions seen from November 2012 to October 2018 were enrolled retrospectively. The patients were treated with US -guided percutaneous MWA and were followed up with contrast-enhanced US and computed tomography or magnetic resonance imaging. Technical success was achieved 20 tumors. The 18 lesions were performed to ablate 90%; 2 lesions were repeated because of detecting residual ablated tumor. Except six patients were noted fever, no severe complications occurred. The median follow-up time was 24 months (range 7-59 months). Among the eight patients, there was no local tumor recurrence in 6 of 8 completely ablated tumor lesions. One patient was retreated by MWA 6 months after ablation, and another was retreated after 19 months due to local tumor recurrence. No patients have obvious change of renal function and lost their life. US-guided percutaneous MWA is a beneficial treatment for BRCC.

Capsule and Ablation Tract Related Features of Local Recurrence in Ultrasound Guided Microwave Ablation of Liver Metastases

Aim: To evaluate the capsule and ablation tract related features of local recurrence after ultrasound (US) guided percutaneous microwave ablation (MWA) of the liver metastases independently.&#x0D; Methods: Between February 2016 and December 2019, 101 patients with US-guided percutaneous MWA of the liver metastases were analyzed. Nineteen patients having thirty-two ablated lesions with local recurrence (LR) were included in the study. Histopathologic type of tumor, preablative features of the lesions and the ablation procedure data were noted. Tumor size, the closest distance between the lesion and the liver capsule was measured. The site of LR related to the liver capsule and related to ablation tract and the shape of the LR were noted&#x0D; Results: The median time of LR was 8.46±4.54 months (range, 3-20). The patient (n=19) and the ablated lesion (n=32) depended LR rates were 19% and 20% respectively. All LR of the parenchymal localized metastatic lesions originated from either tip or the side of the ablation tract and this relationship was found as statistically significant (p=0.035). no statistically significant relationship was found between vessel closeness and shape of LR (p=0,704) and between the site and the shape of LR (p=0.683). &#x0D; Conclusion: We defined some features of LR related to the ablation tract and liver capsule independently such as the relation between the recurrence and the blood vessel proximity, side of the LR throughout the ablation tract and its relation with the liver capsule.

Actual More than 10 Years Survivor after Ultrasound-Guided Percutanouse Microwave Ablation for Hepatocellular Carcinoma

Background: We aimed to evaluate the risk factors of survival outcome after US-guided percutaneous microwave ablation (US-PMWA) for HCC patients with more than 10 years follow-up period. Methods: A single center study from China involving treatment-naive HCC patients met the Milan criteria who received US-PMWA between April 2002 and October 2008. As validation, 130 HCC patients were screened out from 373 ones, and the data was analyzed. Thirty-three patients survived more than 10 years, and 97 less. Univariate analysis was assessed by the Kaplan-Meier method with log-rank test. Cox proportional hazard regression model based on risk factors for OS in HCC patients after US-PMWA was used to construct the nomogram. Findings: The median time of RFS and OS were 2.1 and 7.9 years, respectively. The 1, 3, 5, and 10-year RFS and OS rates were 75.3%, 41.2%, 32.5% and 23.1%, and 90.9%, 68.0%, 61.1% and 25.4, respectively. Univariate analysis showed that age (P=0.002), comorbidities (P=0.016), CTP grade (P=0.036) and preoperative TACE (P=0.023) were risk factors for OS, and multivariate analysis results showed that age (≥65 years) (P=0.004, HR 2.005, 95%CI 1.251-3.212), comorbidities (P<0.001, HR 0.600, 95%CI 0.494-0.727) and early recurrence (P=0.025, HR 1.717, 95%CI 1.070-2.754) were independently associated with poor OS. The nomograms were developed on the basis of above variables. Internal validation had good concordance index of 0.769 (95%CI 0.699, 0.839) in OS. Interpretation: The results suggest that early HCC patients with younger age, no comorbidities and late/no recurrence would be benefit to more than 10 years survival after US-PMWA. Fund: This work was supported by the National Key RD 2017FC-CXYY-3005 from the Clinical Research Support Foundation of the Chinese PLA General Hospital. Funding Statement: This work was supported by the National Key RD 2017FC-CXYY-3005 from the Clinical Research Support Foundation of the Chinese PLA General Hospital. Declaration of Interests: The authors declare no conflict of interest. Ethics Approval Statement: Written informed consent was obtained from each enrolled patient, and the protocol was approved by the Institutional Ethics Committee.

Differences in treatment outcomes between ultrasound-guided percutaneous microwave ablation and endoscopic thyroidectomy for patients with papillary thyroid microcarcinoma: Protocol for a systematic review and meta-analysis.

Background:The differences in treatment outcomes between ultrasound (US)-guided percutaneous microwave ablation (PMWA) and endoscopic thyroidectomy for patients with papillary thyroid microcarcinoma (PTMC) remains unknown.Methods:An electronic search will be performed for randomized controlled trials or observational studies that reported recurrence and mortality rates in PTMC patients with US-guided PMWA or endoscopic thyroidectomy. Hazard ratios with their 95% confidence intervals will be calculated using fixed- or random-effects models according to heterogeneity.Results:This study will present the differences in treatment outcomes between US-guided PMWA and endoscopic thyroidectomy for patients with PTMC by pooling the results of individual studies.Conclusion:The results of this study would provide vigorous evidence in this issue and offer the guidance to both clinical decision-making and future research.Ethics and dissemination:Ethical approval is not applicable for this study.PROSPERO registration number:CRD42018112320.

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.

A propensity score matching study between ultrasound-guided percutaneous microwave ablation and conventional thyroidectomy for benign thyroid nodules treatment

Purpose: Our study aims to compare ultrasound (US)-guided percutaneous microwave ablation (PMWA) and conventional thyroidectomy in benign thyroid nodules (BTN) treatment.Materials and methods: From December 2015 to December 2017, a total of 280 patients with at least one benign thyroid nodule were studied retrospectively, including 156 patients treated with US-guided PMWA and 124 patients treated with conventional thyroidectomy. Propensity score matching was performed to decrease the confounding bias due to retrospective assignment and to balance the pre-operation data of the two groups. A total of 106 pairs (1:1) was created. The operation time, intraoperative blood loss, postoperative hospitalization time, serum levels of interleukin (IL-6), C-reactive protein (CRP), tumor necrosis factor-α (TNF-α) 12 h after operation and postoperative complications incidence rate were compared between the two groups. The volume reduction ratio was calculated in the US-guided PMWA group at 1, 3, 6 and 12 months after treatment. Registration number: ChiCTR1800015531.Results: Significant differences were found between the two groups in levels of CRP, IL-6, and TNF-α after the operation； there were significant differences between the two groups in intraoperative blood loss, operation time, postoperative hospitalization time and postoperative complications rate. The volume reduction ratio at 1, 3, 6 and 12 months after treatment was 15.2%, 47.6%, 67.2% and 79.6%, respectively.Conclusions: Our study demonstrated that US-guided PMWA is characterized by a definite therapeutic success rate, good cosmetic effect, slight injury and rapid recovery. US-guided PMWA is an effective technique for benign thyroid nodules treatment．

Local tumor progression after ultrasound-guided percutaneous microwave ablation of stage T1a renal cell carcinoma: risk factors analysis of 171 tumors

Purpose: To retrospectively review long-term oncologic outcomes after ultrasound (US)-guided percutaneous microwave ablation (MWA) of T1a renal cell carcinoma (RCC) and to identify the incidence and risk factors that predict local tumor progression (LTP) after MWA of RCC.Materials and methods: The present study was approved by the institutional review board. A total of 162 patients with 171 RCC nodules (mean size, 2.6 ± 0.8 cm; range, 0.6–4.0 cm) were treated by MWA between April 2006 and January 2017. The influence of eight factors (age; sex; longest tumor diameter; tumor number, location and pathology type; ablation power and time) affecting the risk of LTP was assessed. Univariate Kaplan–Meier and Cox proportional hazard models were used for statistical analysis.Results: LTP occurred in five patients (5 tumors) after US-guided percutaneous MWA of stage T1a RCC. The overall occurrence of LTP was 2.9% per tumor and 3.0% per patient with a median follow-up of 45.5 months. Among the 162 patients, there were no instances of LTP-related deaths; however, 20 patients died of other diseases. All patients with LTP survived through follow-up. The survival rate of LTP-free patients at 1, 3 and 5 years were 98.7%, 89.5% and 82.1%, respectively (p = .38). Univariate and multivariate analysis identified tumor location to be the only independent predictor of LTP.Conclusions: US-guided percutaneous MWA for T1a RCC achieved a relatively low LTP incidence rate. Tumors adjacent to the renal pelvis or bowel increased the potential of LTP occurrence.

Comparison of ultrasonography-guided percutaneous microwave ablation for subcapsular and nonsubcapsular hepatocellular carcinoma

PurposeTo compare the prognosis of subcapsular and nonsubcapsular hepatocellular carcinoma (HCC) after ultrasonography (US)-guided percutaneous microwave ablation (MWA). Materials and methodsFrom January 2012 to December 2015, 463 enrollment patients (382 men, 81 women; age range, 24–95 years) with a single HCC underwent US-guided percutaneous MWA. The patients were divided into two groups according to tumor location: subcapsular (n=224) and nonsubcapsular (n=239). Therapeutic efficacy was assessed by contrast enhanced imaging after MWA. The technique effectiveness rate, the local tumor progression (LTP) rate, overall survival (OS) rate and complication were compared between two groups. ResultsThere were no significant differences in the mean treatment sessions (p=0.105) and the mean number of antenna insertions (p=0.065) between two groups. No significant difference in the technique effectiveness rate was found between subcapsular and nonsubcapsular tumors (95.5% vs 98.3%, p=0.089). The respective 1-, 2-, 3-, and 4-year cumulative LTP rates were 5.0%, 5.5%, 5.5% and 5.5% in subcapsular group and 6.4%, 6.4%, 6.4% and 6.4% in nonsubcapsular group, respectively(p=0.861). The 1-, 2-, 3-, and 4-year OS rates were estimated to be 95.7%, 90.1%, 82.9%, and 71.1% in subcapsular group and 98.5%, 92.8%, 83.2%, and 73.6% in nonsubcapsular group, respectively (p=0.426). There was no significant difference in major complication rates between the subcapsular group (2.2%) and nonsubcapsular group (1.3%) (p=0.653). There was higher postoperative pain rate in subcapsular group (13.4%) than nonsubcapsular group (7.1%) (p=0.025). ConclusionsThere were no significant differences in the technique effectiveness rate, cumulative LTP rate, OS rate and major complication rate between subcapsular and nonsubcapsular group after MWA for HCC.

Combination therapy of three-dimensional (3D) visualisation operative treatment planning system and US-guided percutaneous microwave ablation in larger renal cell carcinomas (D ≥ 4 cm): preliminary results

Purpose: To analyse the clinical outcomes of combination therapy of three-dimensional (3D) visualisation operative treatment planning system and US-guided percutaneous microwave ablation (PMWA) in larger renal cell carcinomas (RCCs) (D ≥ 4 cm).Materials and methods: The results from 20 patients with 20 larger RCCs treated with a 3D visualisation operative treatment planning system and US-guided PMWA were reviewed retrospectively. The patients were followed up by contrast-enhanced images at 1, 3, and 6 months and every 6 months thereafter. The outcomes of overall survival and local tumour progression rate were statistically analysed.Results: The median follow-up period was 26 months. The mean time of ablation for one tumour was 1.1 ± 0.3 sessions. The average number of ablation points of one tumour was 4.5 ± 0.9. The mean output power of ablation was 50.50 ± 2.2 W. The mean time of ablation for one tumour was 1374.4 ± 391.1 s. Artificial ascites was used in 12 (60%) tumours adjacent to the intestinal tract, and thermal monitoring system was used in all tumours (100%). Technical effectiveness and metastasis-free status were achieved in all tumours. The 1- and 2-year local tumour progression rates were both 5%. The cancer-specific survival rate and 2-year overall survival rates were both 100%. No severe major complications occurred. There was no significant difference in creatinine or urea nitrogen before or 3 days after ablation.Conclusions: Combination therapy of 3D visualisation operative treatment planning system and US-guided PMWA appeared to be a safe and effective technique for the management of larger RCCs, which could improve clinical efficacy.

Percutaneous microwave ablation for benign focal liver lesions: Initial clinical results.

Benign focal liver lesions (BFLLs) have become a common disease diagnosed in the clinical setting following the advancement of imaging techniques. The aim of the present study was to evaluate the safety and clinical outcomes of percutaneous microwave (MW) ablation, guided by ultrasound (US), for the treatment of BFLLs. Between May 2005 and January 2011, 44 BFLLs (mean maximum diameter, 33.9±13.1 mm) in 37 patients (23 women and 14 men) were treated by US-guided percutaneous MW ablation with cooled-shaft antennae. The pathological diagnosis of a BFLL was confirmed in 91.9% (34/37) of patients using a US-guided core needle biopsy prior to ablation. The BFLLs in the other 3 cases were diagnosed by typical presentations on contrast-enhanced imaging, as the patients refused to undergo biopsies. Five inclusion criteria, including indeterminate diagnoses of nodules on contrast-enhanced imaging prior to pathological verification, were recommended. The median follow-up period was 27.0 months (range, 6-73 months). The mean MW ablation energy and time were 55.0±41.6 kJ (range, 13.5-207 kJ) and 1,039.9±706.2 sec (range, 270-3,450 sec) per lesion, respectively. In total, 40 nodules (90.9%) were completely ablated, and no evidence of recurrence was demonstrated on contrast-enhanced imaging follow-up. The other 4 nodules (9.1%) were partially ablated due to the proximity of adjacent vital organs. Minor complications without sequelae included local pain and transient hemoglobinuria and no major complications occurred in peri-ablation. Overall, US-guided percutaneous MW ablation is a safe, effective and minimally invasive therapy for BFLLs in selected patients who are non-surgical candidates.

Microwave treatment of renal cell carcinoma adjacent to renal sinus

PurposeTo evaluate the efficacy and safety of ultrasound (US)-guided percutaneous microwave ablation (MWA) for renal cell carcinoma (RCC) adjacent to renal sinus. Materials and methodsThis retrospective study included 41 patients who underwent US-guided percutaneous MWA of 41 RCCs adjacent to the renal sinus from April 2006 to December 2015. Contrast-enhanced images of US and computed tomography (CT) or magnetic resonance (MR) imaging were performed at pre-ablation and 1day, 1 month, 3 months, and every 6 months after ablation. Initial ablation success (IAS), disease-free survival (DFS), RCC-related survival (RRS), and overall survival (OS) were recorded at the follow-up visits. ResultsIAS was achieved in 92.7% (38/41) of the study subjects. The IAS significantly differed between patients with RCCs ≤4cm (100%, 29/29) and RCCs >4cm (75%, 9/12, p=0.021). During the median follow-up of 37.6 (range, 3.0–97.3) months, the estimated 1-, 3-, and 5-year DFS of patients with an initial tumor of ≤4cm were 100%, 89.7%, and 81.5%, respectively. The 1-, 3-, and 5-year RRS were 100%, 93.3%, and 93.3%, respectively. The 1-, 3-, and 5-year OS were 97.1%, 87.8%, and 83.6%, respectively. The multivariate analysis using the Cox proportional hazard model revealed no independent predictor of recurrence among all the variables. There were no MWA-related deaths among the study subjects. One patient developed a retroperitoneal abscess after ablation. ConclusionUS-guided percutaneous MWA appears to be a promising method for RCCs adjacent to renal sinus, especially for tumors ≤4cm.

Complications of ultrasound-guided percutaneous microwave ablation of renal cell carcinoma.

PurposeTo retrospectively review the complications of ultrasound (US)-guided percutaneous microwave ablation (MWA) of renal cell carcinoma.Patients and methodsIn this study, 101 patients with 105 tumors seen from April 2006 to Feb 2014 were enrolled retrospectively. The patients were treated with US-guided percutaneous MWA and were followed up with contrast-enhanced US and computed tomography or magnetic resonance imaging at 1, 3, and 6 months and every 6 months thereafter.ResultsTechnical success was achieved in 99 of 105 tumors (94.3%). The median follow-up time was 25 (range 1.13–93.23) months. Among the 105 tumors, 26 complications in 24.8% of patients and 23 minor complications (Clavien–Dindo Grades I and II) in 21.9% of patients were noted, accounting for 88.5% of all complications. All the minor complications were cured. Three major complications (Clavien–Dindo Grade ≥III) occurred in 2.9% of the patients, accounting for 11.5% of all complications: hydrothorax in two patients and bowel injury in one. The two patients who had hydrothorax post-MWA had a history of cirrhosis and were treated with catheter drainage. The bowel injury was treated surgically. In all patients, the changes in serum creatinine and urea nitrogen levels from before to after the procedure were small.ConclusionUS-guided percutaneous MWA is a beneficial treatment for renal cell carcinoma in selected patients; however, if the renal tumor is close to the bowel, or the patient has serious comorbidities or has undergone abdominal surgery, the procedure must be performed more carefully.

US-Guided Percutaneous Microwave Ablation for Primary Hyperparathyroidism with Parathyroid Nodules: Feasibility and Safety Study

PurposeTo test the feasibility, safety, and efficacy of microwave (MW) ablation for primary hyperparathyroidism (pHPT) in patients who are unsuited or unwilling to undergo surgery. Materials and MethodsFifteen patients with benign parathyroid nodules were treated with MW ablation. Ultrasound, laboratory data, and clinical symptoms were evaluated before treatment; 1 week and 1, 3, 6, and 12 months after treatment; and every 6–12 months thereafter. ResultsAll patients were followed up for more than 1 year, with an average duration of 32.8 months ± 17.9. Eleven patients underwent successful ablation in a single session, and two patients with bilateral disease and two patients with residual disease were treated with two sessions each. The rate of complete nodule disappearance was 17.6%. Nodule volume and serum parathyroid hormone (PTH) and calcium levels were significantly lower at the last follow-up than before treatment (volume, 0.39 cm3 ± 0.69 vs 2.62 cm3 ± 3.32; PTH, 54.5 pg/mL ± 24.1 vs 592.5 pg/mL ± 579.1; and calcium, 2.32 mmol/L ± 0.12 vs 2.93 mmol/L ± 0.47; P < .01). Treatment was well tolerated. Minor complications included transient voice change in one patient. ConclusionsMW ablation is a safe and effective technique for the treatment of pHPT. It is a good alternative for patients who do not meet surgery criteria or decline surgery.

Ultrasound-guided percutaneous microwave ablation for hepatic malignancy adjacent to the gallbladder

Purpose: The study was performed to assess the safety and efficacy of ultrasound (US)-guided percutaneous microwave (MW) ablation for hepatic malignancy adjacent to the gallbladder. Materials and methods: From January 2011 to December 2013, 49 patients with 51 hepatic tumours adjacent to the gallbladder who underwent US-guided percutaneous MW ablation were included in the study group. A total of 106 patients with 117 hepatic tumours not adjacent to the gallbladder who underwent US-guided percutaneous MW ablation were included in the control group. In the study group the temperature of marginal ablation tissue proximal to the gallbladder was monitored and controlled at 45–54 °C for 5–10 min during the ablation. Ethanol (4.5–13 mL) was injected into the marginal tissue in 27 of 51 tumours of the study group. We compared the results of ablation between the two groups. Results: All patients were successfully treated. A total of 47 of 51 tumours in the study group (92.2%) and 110 of 117 tumours in the control group (94.0%) achieved complete ablation (p = 0.93). Local tumour progression was found in nine (17.6%) tumours in the study group and 15 (12.8%) tumours in the control group during follow-up after MW ablation (p = 0.41). No peri-procedural major complications occurred in either group. Conclusions: Under strict temperature monitoring, US-guided percutaneous MW ablation assisted with ethanol injection appears to be safe and can achieve a high rate of complete ablation for the treatment of hepatic malignant tumours adjacent to the gallbladder.

Ultrasound-guided percutaneous microwave ablation for adenomyosis: efficacy of treatment and effect on ovarian function.

A total of 142 premenopausal women with symptomatic adenomyosis underwent ultrasound (US)-guided percutaneous microwave ablation (PMWA) at the Chinese PLA General Hospital. This study aimed to evaluate changes in serum pituitary, gonadal hormone and cancer antigen 125 (CA125) levels after US-guided PMWA. Therefore, estradiol (E2), follicle-stimulating hormone (FSH), prolactin (PRL) and CA125 levels were evaluated before ablation and at 3, 6, 9 and 12 months after ablation. No significant differences were observed in the E2 and FSH levels pre-ablation and during follow-up (E2: p = 0.933, p = 0.987, p = 0.106, p = 0.936; FSH: p = 0.552, p = 0.295, p = 0.414, p = 0.760). The mean absolute values of serum CA125 and PRL were significantly decreased at 3, 6, 9 and 12 months after ablation (CA125: p < 0.001, p < 0.001, p < 0.001, p = 0.003; PRL: p < 0.001, p < 0.001, p < 0.001, p < 0.001). A significant correlation between changes in CA125 levels and uterine volume was found (p < 0.001). No evidence of a decline in ovarian function was observed after US-guided PMWA.