A clinical study of thermal monitoring techniques of ultrasound-guided microwave ablation for hepatocellular carcinoma in high-risk locations.

To confirm the safety and effectiveness of the minimally invasive thermal monitor technique on percutaneous ultrasound-guided microwave ablation (MWA) for hepatocellular carcinoma (HCC) in high-risk locations, a total of 189 patients with 226 HCC nodules in high-risk locations were treated with MWA. The real-time temperature of the tissue between the lesion margin and the vital structures was monitored by inserting a 21G thermal monitoring needle. The major indexes of technical success, technique effectiveness, local tumour progression and complications were observed during the follow-up period. Technical success was acquired in all patients. Technique effectiveness was achieved with one session in 119 lesions based on contrast-enhanced ultrasound (CEUS) 3-5 days after treatment. An additional 95 lesions achieved technique effectiveness at the second session. Within the follow-up period of 6-58 months (median 38 months), the 1-, 2-, 3-, and 4-year local tumour progression rate was 11.1%, 18.1%, 19.1%, and 19.9%, respectively. There were no major complications in all the patients except for the common side effects. These results indicate that the thermal monitor technique can be applied to prevent major complications in vulnerable structures and allow percutaneous MWA to achieve satisfactory technique effectiveness in the treatment of HCC in high-risk locations.

Long-term effects of ultrasound-guided microwave ablation in the treatment of small renal cell carcinoma / 南方医科大学学报

<p><b>OBJECTIVE</b>To evaluate the long-term efficacy of microwave ablation in the treatment of small renal cell carcinoma (RCC).</p><p><b>METHODS</b>We retrospectively analyzed 140 cases of small cell renal carcinoma (151 lesions with a mean diameter of 2.8±0.8 cm) treated between April, 2006 and October, 2015 with ultrasound-guided microwave ablation with cooled-shaft needle antenna. One microwave ablation antenna was used for tumors less than 2 cm in diameter and 2 antennas were used for larger tumors. The patients received enhanced ultrasound and CT/MRI examinations at 1, 3, and 6 months after the operation and every 6 months thereafter. The overall survival, disease-free survival, and local tumor progression rate of the patients were evaluated.</p><p><b>RESULTS</b>The response rate of treatment (complete ablation at one month on enhanced images) was 100% in these patients. The local tumor progression rates at 1, 3, and 5 years were 0.9%, 2.0%, and 7.1%, respectively, and the 1-, 3-, and 5-year distant metastasis rates were 1.6%, 2.5%, and 7.9%, respectively. The overall survival rates of the patients at 1, 3, and 5 years were 98.4%, 94.8%, 89.5%, respectively, with disease-free survival rates of 98.4%, 93.0%, and 83.1%, respectively. No major complications occurred in these cases, and multivariate analysis showed that the tumor number (P=0.015) and tumor growth patterns (P=0.049) were independent risk factors that adversely affected the long-term outcome after surgery.</p><p><b>CONCLUSION</b>Our data show that microwave ablation is a safe and effective modality for treatment of renal cell carcinoma.</p>

Percutaneous cooled-tip microwave ablation under ultrasound guidance for primary liver cancer: analysis of major complications in 693 patients / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To analyze the major complications of percutaneous cooled-tip microwave ablation for the treatment of primary liver cancer and the possible risk factors of severe complications in a series of 693 patients.</p><p><b>METHODS</b>The clinicopathological data of 693 patients with primary liver cancer who underwent ultrasound-guided percutaneous cooled-tip microwave (MW) ablation in our hospital over the past 5 years were retrospectively analyzed, and the risk factors of severe complications were explored.</p><p><b>RESULTS</b>In a total of 693 patients with 898 primary liver tumors were treated and 1111 MW ablation sessions were performed. The mean diameter of tumors was (2.5 ± 1.2) cm and the range was 0.4 - 10.0 cm. Three deaths occurred in the peri-ablation period, including one case died of multiorgan failure, one case died of pulmonary embolism and one case died of hepatorenal syndrome. Major complications occurred in 27 (3.9%) patients, including 12 pleural effusion requiring thoracentesis (1.7%), 10 tumor seeding (1.4%), 3 liver abscess and empyema (0.4%), 1 hemorrhage requiring arterial embolization (0.1%), and 1 bile duct injury (0.1%). The Chi-square test results showed that the diameter of tumors, number of MW ablation sessions and histological type of tumor were significantly associated with the major complications rate (P < 0.05). The multiple variables 1ogistic regression analysis showed that only type of tumors was associated with the major complication rate (P < 0.05).</p><p><b>CONCLUSIONS</b>Results of this study confirm that cooled-tip MW ablation is a relatively low-risk and effective minimally invasive procedure for the treatment of primary liver cancer. Proper direction for the treatment of cholangiocarcinoma (ICC) patients as well as fewer ablated tumor numbers during one hospital stay may help minimize the major complication rate in patients with primary liver cancer treated by ultrasound-guided percutaneous cooled-tip microwave ablation.</p>