Although surgical resection remains to be the best treatment strategy for stageⅠnon-small cell lung cancer (NSCLC), percutaneous thermal ablation offers an important option for patients who are unable to undergo surgical resection. Currently, there are three main thermal ablation methods used in the treatment of lung cancer, including radiofrequency ablation (RFA), microwave ablation (MWA) and argon-helium cryoablation (AHC). With the improvement of technique and the accumulation of experience in the treatment of lung cancer, some limitations are disclosed in the initial application of RFA, such as heat sink effect, skin burns and rapid carbonization. These shortcomings have been overcome in the development of MWA and AHC. The feasibility and safety of thermal ablation for the treatment of lung cancer has been demonstrated and its efficacy has been significantly improved (especially for the tumour diameter≤3 cm). This article will focus on the application and recent research developments of these ablation techniques in the treatment of lung cancer.
Increasing peripheral pulmonary nodules are detected given the growing adoption of chest CT screening for lung cancer. The invention of electromagnetic navigation bronchoscope provides a new diagnosis and treatment method for pulmonary nodules, which has been demonstrated to be feasible and safe, and the technique of microwave ablation through bronchus is gradually maturing. The one-stop diagnosis and treatment of pulmonary nodules can be completed by the combination of electromagnetic navigation bronchoscopy and microwave ablation, which will help achieve local treatment through the natural cavity without trace.
The precise anatomical division of liver segments is the foundation of liver surgery, while the anatomical division of the S9 segment of liver is a further precise division of the caudate lobe of the liver. This article retrospectively analyzed and summarized the precise minimally invasive ablation and follow-up results of four representative lesions of the S9 segment of liver, including primary liver cancer, recurrent liver cancer, metastatic liver cancer, and focal liver hyperplasia, treated at Affiliated Dongguan Hospital of Southern Medical University. The aim of this study is to explore the minimally invasive ablation effect of lesions located at the S9 segment of liver under CT guidance.
ObjectiveTo investigate the feasibility and safety of DynaCT microwave ablation (MWA) guided by 3D iGuide puncture technology for lung cancer.MethodsThe clinical data of 19 patients with primary or metastatic lung cancer who underwent DynaCT MWA from June 2019 to December 2020 in our hospital were retrospectively analyzed, including 15 males and 4 females with an average age of 64.9±11.7 years. The technical success rates, adverse reactions and complications, postoperative hospital stay, and local therapeutic efficacy were recorded.ResultsTechnical success rate was 100.0%. The mean time required to target and place the needle was 15.7±3.7 min and the mean ablation time was 5.7±1.6 min. Thirteen patients underwent biopsy synchronously before the ablation, and 10 (76.9%) patients had positive pathological results. The main adverse reactions were pain (7/19, 36.8%), post-ablation syndrome (4/19, 21.1%) and cough (2/19, 10.5%). The minor complications were pneumothorax (6/19, 31.6%), hemorrhage (5/19, 26.3%), pleural effusion (2/19, 10.5%) and cavity (1/19, 5.3%). Three patients had moderate pneumothorax and received closed thoracic drainage. The median hospitalization time after ablation was 2.0 (2.0, 3.0) d, and no patient died during the perioperative period. The initial complete ablation rate was 89.5% (17 patients) and the incomplete ablation rate was 10.5% (2 patients) at 1-month follow-up, and no local progression was observed.ConclusionDynaCT MWA of lung cancer under the guidance of 3D iGuide system is safe and feasible with a high short-term local control rate, but the long-term efficacy remains to be further observed.
Objective To summarize recent progress of microwave ablation combined with endoscopic technique for liver cancer. Method The literatures relevant to treatment of microwave ablation combined with endoscopic technique for liver cancer in recent years were identified by searching PubMed and CNKI, then summarized and reviewed. Results The treatment of endoscopic microwave ablation or it combined with hepatectomy, interventional embolization, neoadjuvant chemotherapy, and two-step hepatectomy could expand the treatment indications for liver cancer, increase the cure rate, and reduce the intraoperative bleeding, postoperative complications and recurrence. Conclusions Microwave ablation combined with endoscopic technique has less invasion and fast recovery for patient with liver cancer. Multi-disciplinary team collaboration and rational use of varied therapeutic methods in treatment of liver cancer could help to improve treatment effect and prolong survival time of patient.
The feasibility of ultrasound backscatter homodyned K model parametric imaging (termed homodyned K imaging) to monitor coagulation zone during microwave ablation was investigated. Two recent estimators for the homodyned K model parameter, RSK (the estimation method based on the signal-to-noise ratio, the skewness, and the kurtosis of the amplitude envelope of ultrasound) and XU (the estimation method based on the first moment of the intensity of ultrasound, X statistics and U statistics), were compared. Firstly, the ultrasound backscattered signals during the microwave ablation of porcine liver ex vivo were processed by the noise-assisted correlation algorithm, envelope detection, sliding window method, digital scan conversion and color mapping to obtain homodyned K imaging. Then 20 porcine livers’ microwave ablation experiments ex vivo were used to evaluate the effect of homodyned K imaging in monitoring the coagulation zone. The results showed that the area under the receiver operating characteristic curve of the RSK method was 0.77 ± 0.06 (mean ± standard deviation), and that of the XU method was 0.83 ± 0.08 (mean ± standard deviation). The accuracy to monitor the coagulation zone was (86 ± 10)% (mean ± standard deviation) by the RSK method and (90 ± 8)% (mean ± standard deviation) by the XU method. Compared with the RSK method, the Bland-Altman consistency for the coagulation zone estimated by the XU method and that of actual porcine liver tissue was higher. The time for parameter estimation and imaging by the XU method was less than that by the RSK method. We conclude that ultrasound backscatter homodyned K imaging can be used to monitor coagulation zones during microwave ablation, and the XU method is better than the RSK method.
This paper explored the feasibility of using ultrasonic Nakagami statistic parameter imaging to evaluate the thermal lesion induced by microwave ablation (MWA) in porcine models. In this paper, thermal lesions were induced in livers and kidneys in 5 swines using a clinical MWA system. During this treatment progress, ultrasonic radiofrequency (RF) data were collected. The dynamic changes of Nakagami parameter in the thermal lesion were calculated, and the ultrasonic B-mode images and Nakagami images were reconstructed simultaneously. The contrast-to-noise ratio (CNR) between the thermal lesion and the surrounding normal tissue was calculated over the MWA procedure. After MWA, a bright hyperechoic region appeared in the ultrasonic Nakagami image as an indicator of the thermal lesion and this bright spot enlarged with lesion development during MWA exposure. The mean value of Nakagami parameter in the liver and kidney increased from 0.78 and 0.79 before treatment to 0.91 and 0.92 after treatment, respectively. During MWA exposure, the mean values of CNR calculated from the Nakagami parameter increased from 0.49 to 1.13 in the porcine liver and increased from 0.51 to 0.85 in the kidney, which were both higher than those calculated from the B-mode images. This in vivo study on porcine models suggested that the ultrasonic Nakagami imaging may provide an alternative modality for monitoring MWA treatment.
ObjectiveTo compare the efficacy and safety of computed tomography (CT)-guided percutaneous versus electromagnetic navigation bronchoscopy (ENB)-guided microwave ablation (MWA) for the treatment of pulmonary nodules. MethodsA retrospective analysis was conducted on the data of high-risk pulmonary nodule patients who underwent MWA at the Nanjing Drum Tower Hospital between 2022 and 2023. The pathological diagnosis rate, complications, and progression-free survival (PFS) were compared between the CT group and the ENB group. ResultsThe CT group included 61 patients, while the ENB group comprised 53 patients. The pathological diagnosis rate in the CT group was slightly higher than that in the ENB group (88.52% vs. 71.69%, P=0.03). However, the ENB group exhibited a lower incidence of perioperative complications, including pneumothorax (16.39% vs. 3.77%, P=0.03), hemoptysis (19.67% vs. 5.66%, P=0.05), and pain (22.95% vs. 7.54%, P=0.03). There was no statistically significant difference in PFS between the two groups [HR=1.17, 95%CI (0.23, 5.81), P=0.85]. ConclusionBoth CT-guided and ENB-guided MWA are effective treatment modalities for high-risk pulmonary nodules.
In recent years, with the improvement of people's awareness of physical examination and the more accurate detection equipment, the detection rate of pulmonary nodules is getting higher and higher. Surgical resection is the first choice for the treatment of malignant pulmonary nodules, but multiple pulmonary nodules, nodules in complex areas and those with surgical contraindications are not suitable for surgery. As an effective, less invasive and low-cost treatment, ablation has developed rapidly in the treatment of multiple pulmonary nodules. This article introduces the progress of several common ablation techniques (radiofrequency ablation, microwave ablation, cryoablation) in the treatment of multiple pulmonary nodules, the indications and contraindications of ablation techniques, the efficacy evaluation and complications after ablation therapy, and the prospects of ablation techniques in the treatment of multiple pulmonary nodules.
ObjectiveTo evaluate the clinical feasibility and safety of CT-guided percutaneous microwave ablation for peripheral solitary pulmonary nodules.MethodsThe imaging and clinical data of 33 patients with pulmonary nodule less than 3 cm in diameter treated by CT-guided microwave ablation treatment (PMAT) in our hospital from July 2018 to December 2019 were retrospectively analyzed. There were 21 males and 12 females aged 38-90 (67.6±13.4) years. Among them, 26 patients were confirmed with lung cancer by biopsy and 7 patients were clinically considered as partial malignant lesions. The average diameter of 33 nodules was 0.6-3.0 (1.8±0.6) cm. The 3- and 6-month follow-up CT was performed to evaluate the therapy method by comparing the diameter and enhancement degree of lesions with 1-month CT manifestation. Short-term treatment analysis including complete response (CR), partial response (PR), stable disease (SD) and progressive disease (PD) was calculated according to the WHO modified response evaluation criteria in solid tumor (mRECIST) for short-term efficacy evaluation. Eventually the result of response rate (RR) was calculated. Progression-free survival was obtained by Kaplan–Meier analysis.ResultsCT-guided percutaneous microwave ablation was successfully conducted in all patients. Three patients suffered slight pneumothorax. There were 18 (54.5%) patients who achieved CR, 9 (27.3%) patients PR, 4 (12.1%) patients SD and 2 (6.1%) patients PD. The short-term follow-up effective rate was 81.8%. Logistic analysis demonstrated that primary and metastatic pulmonary nodules had no difference in progression-free time (log-rank P=0.624).ConclusionPMAT is of high success rate for the treatment of solitary pulmonary nodules without severe complications, which can be used as an effective alternative treatment for nonsurgical candidates.