Among percutaneous ablation therapies, radiofrequency ablation (RFA) is commonly used for treating lung tumors. Currently, it is expected that use of lung RFA will become increasingly widespread in Japan, as it has been covered by the national health insurance since September 2022. RFA can be used to treat primary and metastatic lung tumors. Preferred candidates for RFA include inoperable patients with stage IA non-small cell lung cancer (NSCLC) and lung oligometastasis. Tumor size and location should be considered in determining the indication for lung RFA. To ensure technical success, the tumor should be ablated with sufficient safety margin using an electrode with an appropriate non-insulated tip length. Multiple overlapping ablation should be performed as needed. Pneumothorax and various other complications can occur after lung RFA. Although serious complications are rare, some complications, such as intractable pneumothorax, interstitial pneumonia, and massive hemorrhage, can be fatal. The literature shows promising local control and survival outcomes after lung RFA in patients with NSCLC and lung metastasis. This review describes basic knowledge that should be known by interventional radiologists who perform lung RFA.

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Japanese health insurance coverage for radiofrequency ablation (RFA) was extended to several diseases in September, 2022. The musculoskeletal tumors “malignant bone tumor”, “osteoid osteoma” and “soft tissue tumor (extremity, chest and abdomen) ” were adopted under the coverage. In this article, we discuss a precise RFA technique and protocol with a focus on patients with metastatic bone tumor and osteoid osteoma.

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With the shift towards minimally invasive treatment, percutaneous thermal ablation, including radiofrequency ablation and cryoablation, can be a promising alternative for small renal tumor treatment. Although there are few reports of the long-term oncological outcomes after thermal ablation of renal tumors, high local tumor control rates and cancer-specific survival rates have been reported. Careful patient selection, adequate understanding of ablation modalities, and outstanding ablation techniques are required for interventional radiologists to maximize the clinical outcomes of renal thermal ablation. Moreover, a close collaboration with urologists is important. In this article, the indications, techniques, safety, and oncological outcomes of thermal ablation for renal tumors are reviewed.

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Radiofrequency ablation (RFA) has been recommended as a first-line treatment for patients with solitary and small hepatocellular carcinoma (HCC) (<2 cm) in Barcelona Clinic Liver Cancer (BCLC) stage 0. This percutaneous image-guided procedure is safe and minimally invasive because it can be performed under moderate intravenous sedation. Additionally, locoregional treatment combined with systemic chemotherapy can improve treatment outcomes in patients with oligometastatic colorectal cancer. RFA is a treatment option for liver metastases from other malignancies, such as neuroendocrine tumors and breast cancer, if the patient is in an oligometastatic condition. Additionally, microwave ablation (MWA), employing a high-frequency band (2.45 GHz) and thermosphere technology, has been introduced as a new ablation modality.
Since 2022, the National Health Insurance in Japan has covered thermal ablation therapy in regions other than the liver and kidney. Therefore, interventional radiologists who are familiar with not only ultrasound but also computed tomography-guided procedures should be more concerned with percutaneous ablation therapy for liver tumors to improve treatment outcomes. Needless to say, a multidisciplinary team approach is needed for hepatic malignancies regardless of whether it is a primary or metastatic disease; however, it is essential for interventional radiologists to be well acquainted with hepatic ablation therapy. Herein, we describe the indications, basic techniques, treatment outcomes, and complications associated with this procedure.

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Central venous ports are commonly used for systemic chemotherapy and nutritional management in home care. Removal of the central venous port from adult patients has been reported. We examined 297 patients who underwent removal of an indwelling forearm central venous port system in the preceding 2 years to determine the factors that prevented removal. The mean age was 68.3±12.0 years; the mean duration of indwelling was 1,066.1±1,071.2 days; the minimum duration was 5 days; and the maximum duration was 5,840 days (approximately 16 years). The most common implantation sites were the left forearm and basilic vein. In 19 (6.4%) cases, removal was unsuccessful. The cutoff for non-removable cases was 1,768 days (4.8 years). We recommend the removal of a central venous port implanted in the forearm for chemotherapy within 4.5 years.

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Placental polyp is a rare disease, consisting of an intrauterine polypoid mass occurring from residual trophoblastic tissue after an abortion, a cesarean section, or a vaginal delivery. It occasionally causes hemorrhage requiring massive blood transfusions. Uterine artery embolization (UAE) is one of the treatment options for placental polyp. Generally, uterine arteries are feeding vessels of the placental polyp, but the left round ligament artery (RLA) was a main feeder in the present case. In case of postpartum hemorrhage, the ovarian artery and RLA are frequently seen collaterals that supply the uterus. However, in the placental polyp, such collaterals are rare, and there have been no reports regarding placental polyp treated by embolization of the RLA. We report a patient who underwent preoperative embolization of the left RLA for placental polyp. Therapeutic approaches including the indications for UAE for the placental polyp and hemodynamic changes in the RLA are also discussed.

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