Daisuke Abo

Lung Radiofrequency Ablation in Patients With Pulmonary Metastases From Musculoskeletal Sarcomas

The authors retrospectively evaluated the impact of lung radiofrequency (RF) ablation on survival in patients with lung metastases from musculoskeletal sarcomas.

Real-time tumor-tracking radiotherapy for adrenal tumors

PURPOSE To investigate the three-dimensional movement of internal fiducial markers near the adrenal tumors using a real-time tumor-tracking radiotherapy (RTRT) system and to examine the feasibility of high-dose hypofractionated radiotherapy for the adrenal tumors. MATERIALS AND METHODS The subjects considered in this study were 10 markers of the 9 patients treated with RTRT. A total of 72 days in the prone position and 61 treatment days in the supine position for nine of the 10 markers were analyzed. All but one patient were prescribed 48 Gy in eight fractions at the isocenter. RESULTS The average absolute amplitude of the marker movement in the prone position was 6.1+/-4.4 mm (range 2.3-14.4), 11.1+/-7.1 mm (3.5-25.2), and 7.0+/-3.5 mm (3.9-12.5) in the left-right (LR), craniocaudal (CC), and anterior-posterior (AP) directions, respectively. The average absolute amplitude in the supine position was 3.4+/-2.9 mm (0.6-9.1), 9.9+/-9.8 mm (1.1-27.1), and 5.4+/-5.2 mm (1.7-26.6) in the LR, CC, and AP directions, respectively. Of the eight markers, which were examined in both the prone and supine positions, there was no significant difference in the average absolute amplitude between the two positions. No symptomatic adverse effects were observed within the median follow-up period of 16 months (range 5-21 months). The actuarial freedom-from-local-progression rate was 100% at 12 months. CONCLUSIONS Three-dimensional motion of a fiducial marker near the adrenal tumors was detected. Hypofractionated RTRT for adrenal tumors was feasible for patients with metastatic tumors.

Percutaneous transluminal angioplasty for hepatic artery stenosis after living donor liver transplantation

The purpose of this study was to evaluate the efficacy of percutaneous transluminal angioplasty (PTA) for treatment of hepatic artery stenosis after living donor liver transplantation. Eighteen patients with hepatic artery stenosis after living donor liver transplantation were included in this study. The success rate and complications of PTA and recurrent stenosis of the hepatic artery were evaluated. Seventeen of 18 patients (94.4%) were successfully treated without complication by a first PTA procedure. Recurrence of hepatic artery stenosis occurred in 6 patients (33.3%). Repeated PTA was performed 12 times for the 6 patients. Two complications occurred as arterial dissection and perforation. As a consequence, the complication rate was 6.7%, involving 2 of 30 procedures in total. In conclusion, PTA is effective for treatment of hepatic artery stenosis after living donor liver transplantation without an increase in the complication rate. Liver Transpl 12:465–469, 2006.

Outcome of MR-guided percutaneous cryoablation for hepatocellular carcinoma

PURPOSE To assess the mid-term results of MR-guided percutaneous cryoablation for small hepatocellular carcinoma (HCC). METHODS Using an argon-based cryoablation system, MR-guided percutaneous cryoablation was performed. The number of tumors was three or fewer. The maximum diameter of tumors was less than 5 cm when solitary and no more than 3 cm when multiple. The Kaplan-Meier method was used to calculate the survival of patients. RESULTS Among 15 patients, 16 tumors were treated. The maximum tumor diameter ranged from 1.2 to 4.5 cm, with a mean of 2.5 +/- 0.8 cm (mean +/- standard deviation). The volume of iceballs measured on MR-images was greater than that of the tumors in all cases. The follow-up period ranged from 10 to 52 months, with a mean of 36.6 +/- 12.1 months. One-year and 3-year overall survival were 93.8 and 79.3%, respectively. The complete ablation rate was 80.8% at 3 years. Immediate complications were pneumothorax, hemothorax, and pleural effusion. An ablation zone was not absorbed and content exuded from a scar of the probe tract 4 months after cryoablation in one patient. CONCLUSION MR-guided percutaneous cryoablation appears to be a feasible modality and potentially good option for the treatment of small HCC.

Stereotactic Radiotherapy for Intracranial Nonacoustic Schwannomas Including Facial Nerve Schwannoma

PURPOSE Although the effectiveness of stereotactic radiosurgery for nonacoustic schwannomas is currently being assessed, there have been few studies on the efficacy of stereotactic radiotherapy (SRT) for these tumors. We investigated the long-term outcome of SRT for nonacoustic intracranial nerve schwannomas. METHODS AND MATERIALS Seventeen patients were treated between July 1994 and December 2006. Of these patients, 7 had schwannomas located in the jugular foramen, 5 in the trigeminal nerve, 4 in the facial nerve, and 1 in the oculomotor nerve. Radiotherapy was used as an initial treatment without surgery in 10 patients (59%) and after initial subtotal resection in the remaining patients. The tumor volume ranged from 0.3 to 31.3 mL (mean, 8.2 mL). The treatment dose was 40 to 54 Gy in 20 to 26 fractions. The median follow-up period was 59.5 months (range, 7.4-122.6 months). Local control was defined as stable or decreased tumor size on follow-up magnetic resonance imaging. RESULTS Tumor size was decreased in 3 patients, stable in 13, and increased in 1 after SRT. Regarding neurologic symptoms, 8 patients (47%) had improvement and 9 patients were unchanged. One patient had an increase in tumor size and received microsurgical resection at 32 months after irradiation. No patient had worsening of pre-existing neurologic symptoms or development of new cranial nerve deficits at the last follow-up. CONCLUSIONS SRT is an effective alternative to surgical resection for patients with nonacoustic intracranial nerve schwannomas with respect to not only long-term local tumor control but also neuro-functional preservation.

Efficacy of therapy for advanced hepatocellular carcinoma: intra-arterial 5-fluorouracil and subcutaneous interferon with image-guided radiation.

Background and Aim:  To evaluate the efficacy of intra‐arterial 5‐fluorouracil (5‐FU) and subcutaneous interferon (IFN) combined with image‐guided radiation therapy (IGRT) in advanced hepatocellular carcinoma (HCC) with portal vein tumor thrombosis (PVTT).

Magnetic resonance-guided percutaneous cryoablation of uterine fibroids: early clinical experiences.

PurposeUterine fibroids (leiomyomas) are the most common tumors of the uterus. The present study evaluated the feasibility and effectiveness of magnetic resonance (MR)-guided percutaneous cryoablation for uterine fibroids as a minimally invasive treatment alternative.MethodsFrom August 2001 to June 2002, MR-guided percutaneous cryoablation was performed on seven uterine fibroids in 6 patients who displayed clinical symptoms related to tumors. Using a horizontal-type open MR system, cryoablation probes were percutaneously placed in fibroids. Fibroids were ablated, and the site and size of ice balls were monitored on MR imaging. Postoperatively, patients completed a questionnaire to assess changes in presenting clinical symptoms, and MR images were obtained for all patients at follow-up. Changes in clinical symptoms and tumor volume were evaluated in each patient.ResultsAll treated patients showed reductions in tumor size. Mean volume reduction rate was 40.3% at 6 weeks postoperatively, and 79.4% at 9–12 months. All patients reported fever after treatment. Surgical drainage was required for abscess in the probe channel in one patient, and transient liver damage occurred in another. Subjective symptoms improved in all patients except one who had multiple tumors, and no patient complained of new symptoms after cryoablation during follow-up.ConclusionMR-guided percutaneous cryoablation represents a feasible and effective treatment for uterine fibroids.

Preoperative Percutaneous Transhepatic Portal Vein Embolization With Ethanol Injection

OBJECTIVE The purpose of this article is to evaluate the feasibility and efficacy of preoperative percutaneous transhepatic portal vein embolization with ethanol injection. MATERIALS AND METHODS We retrospectively evaluated 143 patients who underwent percutaneous transhepatic portal vein embolization. Hypertrophy of the future liver remnant was assessed by comparing the volumetric data obtained from CT image data before and after percutaneous transhepatic portal vein embolization. The evaluation of effectiveness was based on changes in the absolute volume of the future liver remnant and the ratio of the future liver remnant to the total estimated liver volume. RESULTS Ten of 143 patients (7.0%) underwent additional embolization because of recanalization and insufficient hypertrophy of the future liver remnant. The mean increase in the ratio of the future liver remnant was 33.6% (p < 0.0001), and the mean ratio of future liver remnant to total estimated liver volume increased from 34.9% to 45.7% (p < 0.0001). Although most of the patients complained of pain after ethanol injection, they were gradually relieved of pain in a few minutes by conservative treatment. Fever (38-39°C) was reported after 47 of 151 (31.1%) percutaneous transhepatic portal vein embolization sessions and was resolved within a few days. Transient elevation of the liver transaminases was observed after the procedures and resolved within about a week. Major complications occurred in nine of 151 (6%) percutaneous transhepatic portal vein embolization sessions, but no patients developed hepatic insufficiency or severe complications precluding successful resection. One hundred twenty patients underwent hepatic resection, and two patients developed hepatic failure after surgery. CONCLUSION Preoperative percutaneous transhepatic portal vein embolization with ethanol is a feasible and effective procedure to obtain hypertrophy of the future liver remnant for preventing hepatic failure after hepatectomy.

Transcatheter Arterial Embolization with Absolute Ethanol Injection for Enlarged Polycystic Kidneys after Failed Metallic Coil Embolization

Kidney enlargement in autosomal-dominant polycystic kidney disease (ADPKD) may cause symptoms by compressing the alimentary tract, lungs, and heart. The clinical symptoms may be progressive, may markedly decrease quality of life, and may even be life-threatening. Although treatment of this disease is often difficult, transcatheter arterial embolization (TAE) with metallic coils has been reported as a renal contraction therapy that is less invasive than surgery. The present report describes a case of ADPKD successfully treated by TAE with absolute ethanol after a previous TAE procedure with metallic coils failed to contract the affected kidneys because of recanalization.

Guidelines on the use of gelatin sponge particles in embolotherapy

Gelatin sponge (GS) is one of the most widely used embolic agents in interventional procedures. There are four commercially available GS products in Japan; however, the endovascular use of Gelfoam and Spongel is off-label, and Gelpart can only be used for hepatic artery embolization and Serescue can only be used for hemostasis of arterial bleeding. GS has been used for a variety of clinical indications, mainly tumor embolization and stopping massive arterial bleeding. The optimal size and preparation procedure of GS particles differs slightly for each clinical indication. In addition, there is a risk of ischemic and/or infectious complications associated with GS embolization in various situations. Therefore, radiologists should be familiar with not only the preparation and handling of GS particles, but also the disadvantages and potential risks, in order to perform GS embolization safely and effectively.