A comparison of single session and multiple session microwave ablation for multiple lung malignancies.

This study aims to retrospectively analyze the safety and effectiveness of microwave ablation (MWA) in treating multiple lung metastases from colorectal cancer. Additionally, it seeks to compare the superiority of single multiple ablation and fractionated multiple ablation for unilateral lung multiple metastases. Retrospective analysis was conducted on clinical and pathological data of 82 patients with such multiple lung metastases from colorectal cancer treated from January 2020 to December 2022. Patients were categorized based on the number of MWA sessions required,Patients who had received only one MWA treatment were included in the single MWA group, and patients who had received two or more MWA treatments were included in the multiple MWA group. Chest-enhanced CT scans were performed at 1, 3, 6, and 12 months post-MWA to assess ablation outcomes. The primary focus was the median overall survival (mOS), while secondary endpoints encompassed median progression-free survival (mPFS), technical success rates, and safety. Analysis was performed by log-rank test and Cox proportional hazard regression model, using the Common Terminology Standard for Adverse Events (version 5.0) to assess safety within 28 days after MWA. There were 82 patients with numerous lung metastases from colorectal cancer, and they had a total of 182 lesions. These patients underwent 112 microwave ablation (MWA) treatments. Each patient received at least two MWA treatments for their target lesions. The overall median overall survival (mOS) time for all patients was 25 months, the median progression-free survival (mPFS) time was 21 months. No deaths or severe adverse events occurred as a result of the treatment. The univariate Cox regression analysis indicated that fractional MWA (P=0.007) were adverse prognostic factors for CRC patients with lung metastasis.Upon accounting for various confounding factors, the significance of MWA times (P=0.006) remained pertinent in its association. Furthermore, the group that underwent single MWA showed a superior mOS compared to the group that underwent fractionated MWA (P=0.004). Microwave ablation proves to be a safe and efficacious treatment modality for colorectal cancer-associated multiple pulmonary metastases, offering substantial clinical benefits.

PurposeTo assess the clinical value of drug-eluting bead trans-arterial chemoembolization (DEB-TACE) combined with microwave ablation (MWA) vs. MWA treatment alone for early stage hepatocellular carcinoma (HCC).Materials and methodsConsecutive data from 102 HCC patients at early stage who were referred to our hospital from December 2014 to May 2016 were retrospectively collected. Forty-seven patients underwent DEB-TACE combined with MWA treatment, whereas 55 patients underwent MWA alone. After 1 month of treatment, the tumour responses of the patients were assessed using the mRECIST criteria. Treatment-related complications and hepatic function were also analysed for the two groups. In addition, overall survival (OS) and progression-free survival (PFS) were calculated and compared.ResultsPatients in the combined treatment group (DEB-TACE combined with MWA) presented a better objective response rate (ORR) and disease control rate (DCR) compared with those in the monotherapy group (MWA treatment). The median OS and PFS were longer in the combined treatment group compared with the monotherapy group. Multivariate Cox’s regression further illustrated that DEB-TACE + MWA vs. MWA was an independent protective factor for PFS and OS. No serious treatment-related complications were observed in any of the patients.ConclusionCombined treatment with DEB-TACE appeared to have advantages in prolonging OS and PFS compared to MWA. Therefore, combined treatment was efficient and should be strongly recommended to early stage HCC patients.

Purpose Evaluate efficacy and safety of microwave ablation (MWA) for pulmonary osteosarcoma oligometastases. Methods Twenty-two patients (median age, 16 years [range, 9–41 years]; 15 male) with pulmonary osteosarcoma oligometastases who underwent MWA from January 2018 to December 2023 were included, with 27 MWA sessions for 36 lung metastases. Technical success and complications were evaluated in all 22 patients, while efficacy and survival were evaluated in 19 patients with 24 MWA sessions in treatment of 32 tumors. Technical success was assessed for each tumor. Local tumor control, progression-free survival (PFS) and overall survival (OS) were estimated using Kaplan–Meier method. Complications were classified using Common Terminology Criteria for Adverse Events version 5.0. Results Technical success was achieved in all 36 tumors (100.0%). Local tumor progression occurred in five of 32 tumors (15.6%). The estimated local tumor control rates at 12, 24 and 36 months were 96.9%, 86.1% and 81.5%, respectively. No significant difference in local control was found between tumors ≤ 10 mm and > 10 mm (p = .470). Twelve of 19 patients (63.2%) developed new lung metastases outside the ablation area, including one with concurrent newly developed bone metastases and one with recurrence of primary osteosarcoma. The median PFS was 21.5 months. The estimated OS rates at 12, 24 and 60 months were 100.0%, 94.4% and 94.4%, respectively. Major complications occurred in five of 27 sessions (18.5%). Conclusions MWA preliminarily demonstrates a high technical success rate, notable local tumor control, promising overall survival and acceptable safety for pulmonary osteosarcoma oligometastases.

Background and study aim: In patients suffering from portal hypertension as result of liver cirrhosis, hypersplenism was ranged from 11 to 55%. The aim of our work was to compare between percutaneous microwave ablation (MWA) and partial splenic artery embolization (PSE) in the management of hypersplenism in patients with liver cirrhosis as regard efficacy and safety. Patients and Methods: Sixty patients with liver cirrhosis complicated with splenomegaly and hypersplenism were divided randomly into three groups; Group (1): Twenty patients were underwent one session of MW ablation of splenic parenchyma with target ablation volume about 20%, Group (2): Twenty patients were underwent two sessions of MW ablation of splenic parenchyma with 1 week interval with target ablation up to 40%, Group (3): Twenty patients were underwent PSE. Results: There was an improvement in the hemoglobin, platelet and leucocyte levels in three groups, which was 9.47± 2.14 gm/dl, 42.75 ± 15.4 x103/ mm3 and 2.6±0.5 x103/mm3 before the procedure respectively and become 9.95 ± 2.29 gm/dl, 313.5±99.6 x103/mm3 and 6.88± 1.89 x103/mm3 after one month as regard PSE group. As regard one session of MWA was 9.73±2.02 gm/dl, 45.57±11.2 x103/mm3 and 2.8±0.85 x103/mm3 and become 11.83±0.74 gm/dl, 152±26.43 x103/mm3 and 5.85±1.01 x103/mm3 after one month. As regard two sessions of MWA group; was 9.2±2.15 gm/dl, 40.6± 11.5 x103/mm3 and 2.4±0.55 x103/mm3 and become 12.74±1.2 gm/dl, 183.4± 26.43 x103/mm3 and 6.29±1.17 x103/mm3 after one month. PSE was significantly more effective in the elevation of platelets and leucocytes than other two groups (p=0.00), and two sessions of MWA more than one session of MWA. The two sessions MWA group was significantly higher than other two groups while one session of MWA group was more than PSE group in the elevation of hemoglobin (p=0.00). No mortality occurred in the three groups, but PSE was associated with more serious complications than the other two groups. Conclusion: MWA and PSE were effective in treatment of hypersplenism in patients with liver cirrhosis, while percutaneous MWA has less serious complications than PSE.

To prospectively compare microwave (MW) ablation using a modified internal cooled-shaft antenna with radiofrequency (RF) ablation in in vivo porcine liver and in patients with small hepatocellular carcinoma (sHCC). In an animal study, MW and RF ablations using a cooled-shaft antenna or internally cooled electrode were performed in in vivo porcine liver. Coagulation diameters of both ablations were compared. For clinical study, 42 patients with sHCC were treated with MW or RF ablation. Complete ablation (CA) and local tumour progression (LTP) were compared. MW ablation produced significantly larger ablation zones than RF ablation in both porcine liver and sHCC with an ablated volume of 33.3 ± 15.6 cm(3) vs. 18.9 ± 9.1 cm(3) and 109.3 ± 58.3 cm(3) vs. 48.7 ± 30.5 cm(3), respectively. The CA rate was 95.5 % (21/22) for MW ablation and 95.0 % (19/20) for RF ablation. In a 5.1-month follow-up, the LTP rate was 18.2 % (4/22) in the MW ablation group and 15.0 % (3/20) in the RF ablation group. MW ablation using a modified cooled-shaft antenna produces a larger ablation zone than RF ablation, with an efficacy similar to RF ablation in local tumour control. MW ablation is a safe and promising treatment of sHCC.

Mouse lung tumors were induced in C57BL/6J(female) x A/J(male) F1 mice by a single s.c. injection of urethan. About 6 months later, multiple small-sized lung tumors were detectable in almost all mice. After a further 6 months, some of these tumors became larger than the rest. We examined whether there were any mutational differences among multiple lung tumors in a single mouse. Direct DNA sequencing of a separately amplified Ki-ras gene by polymerase chain reaction (PCR) was carried out with 25 DNA samples from multiple tumors in four mice. Twenty-four of 25 tumors (96%) had mutations at the codon 61 of the Ki-ras gene. The major mutations involved were either AT to GC transition (44%) or AT to TA transversion (44%) at the second base of codon 61. We compared the types of these gene mutations among the tumors from each of two mice from two different groups of siblings and then compared the two groups. Interestingly, in the first group of siblings, we detected CTA in 5/6 tumors in the first mouse and again CTA in 4/6 tumors in the second one. In the second group of siblings, we detected CGA in 5/7 tumors in one mouse and CGA again in 3/5 tumors in the second mouse. These results show that the pattern of Ki-ras codon 61 mutations in urethan-induced lung tumors is similar in tumors developing in siblings, suggesting that host factors have an effect on the carcinogen-induced mutational pattern. There was no major mutational difference between small and large tumors. The results suggested that other event(s) in addition to the mutation of the Ki-ras gene might play a role during the development of large-sized tumors.

The purpose of our study is to report safety, technical success, effectiveness, local progression-free survival (LPFS) and overall survival of percutaneous microwave ablation (MWA) to treat lung tumours unsuitable for surgery. Nineteen patients with thirty-one tumours (mean diameter 2.4cm) underwent percutaneous MWA in 28 sessions. Microwave ablation was carried out using a 2450-MHz generator (Emprint/Covidien, Boulder, CO, USA). Procedures were performed under cone-beam CT (CBCT) and under fluoro-CT (one session) guidance. Safety, technical success, effectiveness, LPFS and overall survival (OS) were evaluated. Safety was defined as the frequency of major and minor complications. The efficacy was evaluated on the basis of imaging characteristics, using RECIST criteria. CT follow-up was performed at 1, 3 and 6months and yearly. LPFS was defined as the interval between MWA treatment and evidence of local recurrence, if there was any. OS was defined as the percentage of patients who were still alive. We registered one major complication (purulent hydro-pneumothorax). Minor complications were spontaneously resolved (pneumothorax and perilesional haemorrhagic effusion). Technical success was 100%. Residual disease was registered in two cases, one of whom was retreated. Complete ablation was obtained in the remaining cases (90.3%). During available follow-up (mean 9.6months), 9/31 tumours demonstrated local recurrence. Five tumours were retreated, and none of them presented residual disease during follow-up (LPFS 22.6%). Overall survival was 93.8%. Percutaneous high-energy MWA is a safe, effective and confident technique to treat lung tumours not suitable for surgery.

Microwave versus Radiofrequency Ablation Treatment for Hepatocellular Carcinoma: A Comparison of Efficacy at a Single Center

Objective: To explore the clinical efficacy of transcatheter arterial chemoembolization, (TACE) combined with CT guided microwave ablation in the treatment of hepatocellular carcinoma. Methods: The patients (45 cases) with hepatocellular carcinoma confirmed by clinical treatment were treated with local microwave ablation with CT guidance after TACE treatment. The changes of alpha fetoprotein (AFP) , local control of tumor and survival rate of the patients were analyzed at 3, 6, 12 and 24 months after treatment. Results: The decrease rates of AFP in 3, 6, 12 and 24 months after operation were 100% (45/45) , 100% (45/45) , 93.3% (42/45) and 91.1% (41/45) , the rates of local control were 100% (45/45) , 100% (45/45) , 97.8% (44/45) and 88.8% (40/45) , and the survival rates were 100% (45/45) , 100% (45/45) , 93.3% (42/45) and 91.1% (41/45) , respectively. TACE treatment showed side effects such as fever, pain, loss of appetite, vomiting and abnormal liver function, and the patients recovered after symptomatic treatment. After microwave ablation, 2 patients had pleural effusion after operation, and the effusion disappeared after symptomatic treatment. No treatment-related death occurred in 45 patients. Conclusions: TACE combined with CT guided microwave ablation could be used in the treatment of hepatocellular carcinoma, the location of CT is accurate, the imaging is obvious, the therapeutic effect is better, and the local control rate of tumor and the effective method of prolonging the life period of the patients are improved. Key words: Liver cancer; Transcatheter arterial chemoembolization (TACE); Microwave ablation; CT guidance

To report the complications for percutaneous microwave (MW) ablation for the treatment of malignant liver tumors and the possible risk factors for complications in a large series of patients. The study was approved by the institutional review board; informed consent was waived because of the retrospective design. Over a 13-year period, 1136 patients with 1928 malignant liver tumors underwent ultrasonographically guided percutaneous MW ablation (583 with a noncooled-shaft antenna and 553 with a cooled-shaft antenna). A total of 3697 MW ablation sessions (average, 1.8 sessions per patient) were performed. Mortality and treatment-related major and minor complications were documented. Data were subsequently analyzed to determine whether the major complication rate was related to antenna type, tumor size, tumor location, or number of MW sessions. Two deaths not directly attributable to MW ablation were encountered. Major complications occurred in 30 (2.6%) patients and included liver abscess and empyema (n = 5), bile duct injury (n = 2), perforation of the colon (n = 2), tumor seeding (n = 5), pleural effusion requiring thoracentesis (n = 12), hemorrhage requiring arterial embolization (n = 1), and skin burn requiring resection (n = 3). Minor complications included fever; pain; asymptomatic pleural effusion, gallbladder wall thickening, and arterioportal shunt; small stricture of the bile duct; and skin burn requiring no treatment. Use of noncooled-shaft antenna and an increased number of MW ablation sessions were associated with a higher rate of major complications (P < .05). MW ablation is a well-tolerated technique with an acceptably low rate of major complications for treatment of malignant liver tumors. Use of a cooled-shaft antenna, as well as fewer MW sessions, may help minimize major complications.

Percutaneous microwave ablation and radiofrequency ablation are two commonly used modalities for the treatment of hepatocellular carcinoma; however, comparisons of them have not been documented adequately. Of 102 patients with biopsy-proved hepatocellular carcinoma, 49 (98 nodules) were treated percutaneously with microwave ablation and 53 (72 nodules) with radiofrequency ablation. The local tumor control, complications related to treatment, and long-term results of the two modalities were compared retrospectively. The complete ablation rates were 94.9% (93/98) using microwave ablation vs 93.1% (67/72) using radiofrequency ablation (P = 0.75), and no significant differences were found either in the ablation of tumors of 3.0 cm or less (P = 1.00) or in those of more than 3.0 cm (P = 1.00) between the two modalities. The local recurrence rates were 11.8% (11/93) using microwave ablation vs 20.9% (14/67) using radiofrequency ablation (P = 0.12), and there were no significant differences between the two modalities either in tumors of 3.0 cm or less (P = 0.36) or in those of more than 3.0 cm (P = 0.82). The rates of major complications associated with microwave ablation and radiofrequency ablation were 8.2% (4/49) vs 5.7% (3/53; P = 0.71). The disease-free survival rates in the microwave ablation group were 45.9%, 26.9%, 26.9%, and 13.4% at 1, 2, 3, and 4 years, respectively, and those in the radiofrequency ablation group were 37.2%, 20.7%, and 15.5% at 1, 2 and 3 years, respectively (P = 0.53). The 1-, 2-, 3-, and 4-year cumulative survival rates for patients who underwent microwave ablation were 81.6%, 61.2%, 50.5%, and 36.8%, respectively, and for patients who underwent radiofrequency ablation the rates were 71.7%, 47.2%, 37.6%, and 24.2%, respectively (P = 0.12). Percutaneous microwave ablation and radiofrequency ablation are both effective methods in treating hepatocellular carcinomas. The local tumor control, complications related to treatment, and long-term survivals were equivalent for the two modalities.

Simple SummaryLung cancer is one of the leading causes of cancer-related mortality worldwide. The incidence of multiple primary lung cancers has been increasing. In addition to the identification of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors, the evaluation of the EGFR mutation status in lung cancer is important to devise optimal treatment strategies. In this study, the EGFR mutation status in multiple primary lung cancers was examined, and its discordance rate in individual tumors was determined to be high. Our findings reveal the importance of EGFR mutation analysis in individual tumors of multiple primary lung cancers.The prevalence of multiple lung cancers has been increasing recently. Molecular analysis of epidermal growth factor receptor (EGFR) mutations in individual tumors of multiple lung cancers is essential for devising an optimal therapeutic strategy. The EGFR mutation status in multiple lung cancers was evaluated to determine its therapeutic implications. In total, 208 tumors from 101 patients who underwent surgery for multiple lung cancers were analyzed. Individual tumors were subjected to histological evaluation and EGFR analysis using a real-time polymerase chain reaction. Additionally, EGFR-wildtype tumors were subjected to next-generation sequencing (NGS). EGFR mutations were detected in 113 tumors from 72 patients, predominantly in females (p < 0.001) and non-smokers (p < 0.001). Among patients with at least one EGFR-mutant tumor, approximately 72% of patients (52/72) had different EGFR mutations in individual tumors. NGS analysis of EGFR-wildtype tumors from 12 patients revealed four and eight cases with concordant and discordant molecular alterations, respectively. These findings revealed a high proportion of discordant EGFR mutations among multiple lung tumors. Hence, EGFR analysis of individual tumors of multiple lung tumors is essential for the evaluation of clonality and the development of an optimal treatment strategy.

Thermal ablative therapies continue to be favored as a safe and effective treatment for patients with non-resectable hepatocellular carcinoma (HCC). Percutaneous microwave ablative therapy, which is a relatively new technique, has the advantage in providing faster ablation of large tumors. This study aimed to evaluate microwave ablation in the treatment of large HCC (5-7 cm) and to assess its effect on local tumor progression, prognostic outcome and patients' survival. In all, 26 patients with large HCC lesions (5-7 cm) were managed in the multidisciplinary clinic of Kasr Al Ainy University hospital using microwave ablation. The treatment was performed with the patient under conscious sedation and analgesia and ultrasonography-guided using an HS AMICA microwave machine operating at frequency of 2450 MHz and a power up to 100 W. Multiple needle insertions were made in one or two sessions according to the size of the lesion. The complete ablation rate, local tumor progression and patients' overall survival were analyzed, and the efficacy and safety of MWA was evaluated. Complete ablation was achieved in 19/26 (73.1%). Local tumor progression was recorded in five treated lesions (19.2%). Distant tumor progression within the liver was recorded in six patients (23.1%), with a mean survival of 21.5 months. No procedure-related major complications or deaths were observed. Percutaneous microwave ablation is safe and effective in the treatment of large HCC tumors. Patients' survival and local tumor control were acceptable.

Microwave ablation (MWA) of lung tumors is a technique that is dependent on the ablationist's level of expertise. The selection of the optimum puncture path and determination of appropriate ablative parameters is the key to the success and safe of the procedure. The objective of this study was to describe the clinical use of a novel three-dimensional visualization ablation planning system (3D-VAPS) for aided MWA of stage I non-small cell lung cancer (NSCLC). This was a single-arm, single-center, retrospective study. From May 2020 to July 2022, 113 consented patients with stage I NSCLC received MWA treatment in 120 MWA sessions. The 3D-VAPS was used to determine that: (1) the overlap between the gross tumor region and simulated ablation; (2) the proper posture and appropriate puncture site on the surface of the body; (3) the puncture path; and (4) presetting preliminarily ablative parameters. Patients were monitored with contrast-enhanced CT scans at 1, 3, and 6 months, as well as every 6 months following that. The primary endpoints were technical success and a complete ablation rate. Local progression-free survival (LPFS), overall survival (OS), and comorbidities were secondary study objectives. The mean diameter of tumors was 1.9 ± 0.4 cm (range 0.9-2.5 cm). The mean duration was 5.34 ± 1.28 min (range 3.0-10.0 min). The mean power output was 42.58 ± 4.23 (range 30.0-50.0W). The median follow-up time was 19.0 months (6.0-26.0 months). The technical success rate was 100%. Three-month after the procedure, the complete ablation rate was 97.35%. 6, 9, 12, and 24 months LPFS rates were 100%, 98.23%, 98.23%, and 96.46%, respectively. One-year and 2-year OS rates were 100% and 100%. There were no patients who died both during the procedure and after the MWA of 30 days. The complications after MWA included pneumothorax (38.33%), pleural effusion (26.67%), intrapulmonary hemorrhage (31.67%), and pulmonary infection (2.50%). This research describes and confirms that 3D-VAPS is a feasibility and safe method for MWA of stage I NSCLC treatment. 3D-VAPS may be helpful to optimize the puncture path, assess reasonable ablative parameters, and minimize complications.

OBJECTIVE. The objective of our study was to evaluate the clinical performance of a new high-frequency (HF) microwave ablation (MWA) technology with spatial energy control for treatment of lung malignancies in comparison with a conventional low-frequency (LF) MWA technology. MATERIALS AND METHODS. In this retrospective study, 59 consecutive patients (mean age, 58.9 ± 12.6 [SD] years) were treated in 71 sessions using HF spatial-energy-control MWA. Parameters collected were technical success and efficacy, tumor diameter, tumor and ablation volumes, ablation time, output energy, complication rate, 90-day mortality, local tumor progression (LTP), ablative margin size, and ablation zone sphericity. Results were compared with the same parameters retrospectively collected from the last 71 conventional LF-MWA sessions. This group consisted of 56 patients (mean age, 60.3 ± 10.8 years). Statistical comparisons were performed using the Wilcoxon-Mann-Whitney test. RESULTS. Technical success was 98.6% for both technologies; technical efficacy was 97.2% for HF spatial-energy-control MWA and 95.8% for LF-MWA. The 90-day mortality rate was 5.1% (3/59) in the HF spatial-energy-control MWA group and 5.4% (3/56) in the LF-MWA group; for both groups, there were zero intraprocedural deaths. The median ablation time was 8.0 minutes for HF spatial-energy-control MWA and 10.0 minutes for LF-MWA (p < 0.0001). Complications were recorded in 21.1% (15/71) of HF spatial-energy-control MWA sessions and in 31.0% (22/71) of LF-MWA sessions (p = 0.182); of these complications, 4.2% (3/71) were major complications in the HF spatial-energy-control MWA group, and 9.9% (7/71) were major complications in the LF-MWA group. The median deviation from ideal sphericity (1.0) was 0.195 in the HF spatial-energy-control MWA group versus 0.376 in the LF-MWA group (p < 0.0001). Absolute minimal ablative margins per ablation were 7.5 ± 3.6 mm (mean ± SD) in the HF spatial-energy-control MWA group versus 4.2 ± 3.0 mm in the LF-MWA group (p < 0.0001). In the HF spatial-energy-control MWA group, LTP at 12 months was 6.5% (4/62). LTP at 12 months in the LF-MWA group was 12.5% (7/56). Differences in LTP rate (p = 0.137) and time point (p = 0.833) were not significant. CONCLUSION. HF spatial-energy-control MWA technology and conventional LFMWA technology are safe and effective for the treatment of lung malignancies independent of the MWA system used. However, HF spatial-energy-control MWA as an HF and high-energy MWA technique achieves ablation zones that are closer to an ideal sphere and achieves larger ablative margins than LF-MWA (p < 0.0001).