Impact of Work Environment on Job Satisfaction among Interventional Radiologists in Japan: A Cross-sectional Study.

Purpose: This study aims to measure job satisfaction among interventional radiology physicians in Japan and analyze the factors affecting job satisfaction. Material and Methods: A web-based survey was conducted among the members of the Japanese Society of Interventional Radiology between October and December 2021. Participants were questioned regarding their job satisfaction, workplace, work status, and demographic information. Principal component analysis was applied to 15 reasons related to job satisfaction, and the factors affecting job satisfaction were analyzed. Results: Valid responses were obtained from 901 (31.9%) of the 2,824 interventional radiology physicians invited to participate. Job satisfaction was reported as "very satisfied" in 79 (8.8%), "moderately satisfied" in 426 (47.3%), "neither satisfied nor dissatisfied" in 230 (25.5%), "moderately dissatisfied" in 133 (14.8%), and "very dissatisfied" in 33 (3.7%) respondents. Thus, there were 505 (56.0%) satisfied physicians. Three principal components were extracted from the reasons for job satisfaction. Job satisfaction tended to be higher among those who reported performing a higher number of interventional radiology procedures and was positively associated with a higher rate of work time dedicated to interventional radiology and the first principal component (the environment of clinical practice, research, and interventional radiology education). The third principal component (salary and work environment) and the absence of an "IkuBoss" [a boss who takes initiative in creating a work environment supportive of the work-life balance of colleagues] were associated with lower job satisfaction. Conclusions: More than half the participants reported high job satisfaction. Job satisfaction of interventional radiology physicians in Japan was positively associated with a favorable clinical, research, and educational environment and negatively associated with the absence of an "IkuBoss," noninterventional radiology work, overtime work, and salary.

Bleeding From a Ruptured, Extraluminally Growing Gastric Gastrointestinal Stromal Tumor Treated by Transcatheter Arterial Embolization: A Case Report.

A 49-year-old man with abdominal pain was referred to our hospital. Abdominal computed tomography showed an extraluminal tumor near the gastric anterior wall and intra-abdominal fluid collection. A ruptured intra-abdominal tumor was suspected, and emergency abdominal angiography was performed. Hemorrhage into the abdominal cavity was seen, and transcatheter arterial embolization (TAE) was performed, which stopped the bleeding. The tumor was surgically resected, and a diagnosis of an extraluminally growing gastric gastrointestinal stromal tumor was made. TAE should be considered for rare cases of extraluminally growing tumors with intra-abdominal hemorrhage.

Impact of the Ablative Margin on Local Tumor Progression after Radiofrequency Ablation for Lung Metastases from Colorectal Carcinoma: Supplementary Analysis of a Phase II Trial (MLCSG-0802).

PURPOSE: To explore what extent of ablative margin depicted by computed tomography (CT) immediately after radiofrequency (RF) ablation is required to reduce local tumor progression (LTP) for colorectal cancer (CRC) lung metastases. MATERIALS AND METHODS: This retrospective study was undertaken as a supplementary analysis of a previous prospective trial. Seventy patients (49 men and 21 women; mean age ± standard deviation, 64.9 years ± 10.6 years) underwent RF ablation for CRC lung metastases, and 95 tumors that were treated in the trial and followed up with CT at least 12 months after RF ablation were evaluated. The mean tumor size was 1.0 cm ± 0.5 cm. The ablative margin was estimated as the shortest distance between the outer edge of the tumor and the surrounding ground-glass opacity on CT obtained immediately after RF ablation. The impact of the ablative margin on LTP was evaluated using logistic regression analysis. Multivariate logistic regression analysis was also performed to identify the risk factors for LTP. The result was validated with multivariate logistic regression applying a bootstrap method (1,000 times resampling). RESULTS: The mean ablative margin was 2.7 mm ± 1.3 (range, 0.4-7.3 mm). LTP developed in 6 tumors (6%, 6/95) 6-19 months after RF ablation. The LTP rate was significantly higher when the margin was less than 2 mm (P = .023). A margin of <2 mm was also found to be a significant factor for LTP (P = .048) on multivariate analysis and validated using the bootstrap method (P = .025). CONCLUSIONS: An ablative margin of at least 2 mm is important to reduce LTP after RF ablation for CRC lung metastases.

Computed tomography-guided biopsy for small renal masses before or immediately after tumor ablation: factors affecting diagnostic yield.

PURPOSE: To evaluate the diagnostic yield of percutaneous renal mass biopsy (RMB) before and after ablation. MATERIALS AND METHODS: In total, 333 renal masses in 332 consecutive patients underwent computed tomography (CT)-guided biopsies and were included in this study. All biopsies were performed with 18-gauge core needles with CT fluoroscopic guidance before ablation (n = 234) or immediately after radiofrequency ablation (RFA) (n = 40) or cryoablation (CA) (n = 59). The safety and diagnostic yield of RMB were evaluated. Both univariate and multivariate analyses were used to identify factors affecting diagnostic yield. RESULTS: No major complication occurred. The 281 specimens (84%) were diagnostic. There were 257 renal cell carcinomas (77%), 21 benign masses (6%), and 3 metastases (1%). The remaining 52 specimens (16%) were nondiagnostic. The diagnostic yields before ablation, after RFA, and CA were 91% (212/234), 80% (32/40), and 63% (37/59), respectively. Small masses (P = 0.050 and 0.006), cystic masses (P < 0.001 and < 0.001), and post-CA (P < 0.001 and < 0.001) were independent and significant factors affecting the nondiagnostic results in both univariate and multivariate analyses. CONCLUSION: CT-guided RMB can be nondiagnostic when the tumor is small, cystic, or biopsied immediately after CA.

Three-year Survival Rate after Radiofrequency Ablation for Surgically Resectable Colorectal Lung Metastases: A Prospective Multicenter Study.

Background Although radiofrequency ablation (RFA) is widely performed for the treatment of colorectal cancer (CRC) lung metastases, its efficacy for candidates with surgically resectable disease is unclear. Purpose To evaluate the prognosis after RFA in participants with resectable CRC lung metastases. Materials and Methods For this prospective multicenter study (ClinicalTrials.gov identifier: NCT00776399), participants with five or fewer surgically resectable lung metastases measuring 3 cm or less were included. Participants with CRC and a total of 100 lung metastases measuring 0.4-2.8 cm (mean, 1.0 cm ± 0.5) were chosen and treated with 88 sessions of RFA from January 2008 to April 2014. The primary end point was the 3-year overall survival (OS) rate, with an expected rate of 55%. The local tumor progression rate and safety were evaluated as secondary end points. The OS rates were generated by using the Kaplan-Meier method. Log-rank tests and Cox proportional regression models were used to identify the prognostic factors by means of univariable and multivariable analyses. Adverse events were evaluated according to the Common Terminology Criteria for Adverse Events, version 3.0. Results Seventy participants with CRC (mean age, 66 years ± 10; 49 men) were evaluated. The 3-year OS rate was 84% (59 of 70 participants; 95% confidence interval [CI]: 76%, 93%). In multivariable analysis, factors associated with worse OS included rectal rather than colon location (hazard ratio [HR] = 7.7; 95% CI: 2.6, 22.6; P < .001), positive carcinoembryonic antigen (HR = 5.8; 95% CI: 2.0, 16.9; P = .001), and absence of previous chemotherapy (HR = 9.8; 95% CI: 2.5, 38.0; P < .001). Local tumor progression was found in six of the 70 participants (9%). A grade 5 adverse event was seen in one of the 88 RFA sessions (1%), and grade 2 adverse events were seen in 18 (20%). Conclusion Lung radiofrequency ablation provided a favorable 3-year overall survival rate of 84% for resectable colorectal lung metastases measuring 3 cm or smaller. © RSNA, 2020 Online supplemental material is available for this article. See also the editorial by Gemmete in this issue.

Successful treatment with cryoablation in a patient with bone metastasis in the mid-shaft femur: a case report.

Background: Treatment of metastatic bone tumors is challenging due to the morbidity associated with patients with metastasis. The present case report described a patient with successful treatment of bone metastasis using cryoablation with plate and cementation to prevent fracture for bone metastasis of leiomyosarcoma in the mid-shaft of the femur. Case report: The metastatic tumor was located at intramedullary lesion of the femur. At first, cryoablation was performed under local anesthesia. After one week after cryoablation, curettage and fixation with plate and cementation were performed to prevent fracture. Tumor cells were not observed in the histopathological findings of the curettage tissue. Four years after cryoablation, there was no recurrence and the patient could walk without any support. Conclusion: We suggest that a tumor with limited cancellous bone and of a small size may undergo cryoablation. The prevention of fracture after cryoablation should be considered.

Cryoablation of renal cell carcinoma for patients with stage 4 or 5 non-dialysis chronic kidney disease.

PURPOSE: To evaluate the safety and efficacy of cryoablation for renal cell carcinoma (RCC) in patients with stage 4 or 5 non-dialysis chronic kidney disease (CKD). MATERIALS AND METHODS: This retrospective multicenter study included patients with maximum tumor diameter ≤ 4 cm, estimated glomerular filtration rate (eGFR) < 30 ml/min/1.73 m2, in whom cryoablation was performed percutaneously with curative intent between July 2011 and May 2016. RESULTS: Of 541 patients who underwent renal tumor cryoablation, 17 (3.1%; 4 women, 13 men; mean age 70.1 ± 10.6 years) with stage 4 or 5 non-dialysis CKD were included in this study. The pre-cryoablation eGFR was 22.5 ± 6.3 ml/min/1.73 m2. The mean tumor diameter was 2.8 ± 0.7 cm. No Grade 3 or higher adverse events occurred post-cryoablation. The eGFR at each time point was significantly lower than that before treatment. One patient required hemodialysis initiation at 21 months post-procedure. None of the patients showed residual RCC at their last follow-up. CONCLUSION: Cryoablation of RCC is safe in patients with stage 4 or 5 non-dialysis CKD and yields treatment results comparable to those in patients without CKD. This treatment could be completed without the early initiation of hemodialysis after the procedure.

Multicenter Phase II Clinical Trial of Sorafenib Combined with Transarterial Chemoembolization for Advanced Stage Hepatocellular Carcinomas (Barcelona Clinic Liver Cancer Stage C): STAB Study.

PURPOSE: To evaluate safety and efficacy of combining sorafenib with transarterial chemoembolization in patients with advanced stage hepatocellular carcinomas (HCCs). MATERIALS AND METHODS: Systemic chemotherapy-naïve patients with a Child-Pugh class A liver profile and advanced stage HCCs were enrolled. Sorafenib therapy (daily dose 800 mg) was initiated within 4 weeks after initial conventional transarterial chemoembolization with an allowance of subsequent on-demand conventional chemoembolization. The primary endpoint was rate of protocol treatment completion, which was defined as sorafenib administration for at least 2 months. Secondary endpoints included objective response rate, disease control rate, overall survival, progression-free survival, and incidence of adverse events. Thirty-one patients (24 men, 7 women; median age, 75 years; vascular invasion, n = 19; extrahepatic metastases, n = 18; both, n = 6) who met the inclusion criteria were enrolled. RESULTS: Protocol treatment was completed in 28 patients (90.3%, 28/31) with median protocol treatment duration of 7.0 months (range, 0.5-30 months) and median of 2 (range, 1-4) transarterial chemoembolization sessions. Objective response rate was 77.4% with median overall and progression-free survival of 17.3 months (95% confidence interval, 11.9-22.6 months) and 5.4 months (95% confidence interval, 4.6-6.2 months), respectively. The most common grade 3 or 4 adverse events were self-limiting elevation of aspartate aminotransferase (54.8%, 17/31) and alanine aminotransferase (45.2%, 14/31). CONCLUSIONS: This combination therapy is feasible and promising in patients with advanced stage HCCs.

Role of curative treatment in patients with intermediate-stage hepatocellular carcinoma.

PURPOSE: To retrospectively evaluate the role of curative treatment in patients with intermediate-stage hepatocellular carcinomas (HCCs), and to identify the subgroup having benefit from curative treatment. METHODS: From April 2000 to December 2014, 100 patients with intermediate-stage HCCs underwent either curative treatment (hepatectomy: n = 23, radiofrequency ablation (RFA); n = 29, both: n = 4) or transarterial chemoembolization (TACE): n = 44) as initial treatments for HCCs. Overall survival, influence of treatment allocation on prognosis, and factors affecting treatment allocation were evaluated. RESULTS: The 5-year survival rate was 59.2% [95% confidence interval (CI) 51.6-66.8%] in the curative group, and 25.1% (95% CI 11.5-38.7%) in the TACE group. Treatment allocation was the only significant prognostic factor (p = 0.014, hazard ratio: 0.382, 95% CI 0.177-0.821). The curative group consisted of more patients with Child-Pugh A (p = 0.0016) than the TACE group, a tumor number of 3 or fewer (p < 0.0001), a unilobar tumor location (p = 0.02), within 4 of 7 cm criterion (p = 0.001), and within up-to-7 criterion (p = 0.04). Child-Pugh A, within the 4 of 7 cm criterion, and a unilobar tumor location were significantly linked with treatment allocation in multivariate analysis. CONCLUSIONS: Curative treatment can prolong survival in selected patients with intermediate-stage HCCs.

Impact of tumor volume doubling time on post-metastatic survival in bone or soft-tissue sarcoma patients treated with metastasectomy and/or radiofrequency ablation of the lung.

Metastasectomy represents the standard treatment for improving survival in patients with lung metastases (LMs) from bone (BS) or soft-tissue sarcoma (STS). Recently, radiofrequency ablation (RFA) of the LMs has been proved to be a useful option which can promise the similar effect to metastasectomy. The aim of this study was to determine prognostic factors, including tumor volume doubling time (TVDT), for post-metastatic survival in BS and STS patients treated with metastasectomy and/or RFA of the lung. Forty-eight patients with LMs were retrospectively reviewed. The mean age of the patients at the time of LMs was 56 years. The cohort comprised 27 male and 21 female patients. Eight of the 48 patients had LMs at the point of initial presentation. The mean follow-up period after commencing the treatment for LMs was 37 months. The mean maximum diameter of the initial LMs was 11 mm. The mean number of LMs was 4. The TVDT was calculated using a method originally described by Schwartz. At last follow-up, 5 patients had no evidence of disease, 3 patients were still alive with disease, and 32 patients had died of disease. The 3-year and 5-year post-metastatic survival rates were 32% and 16.8%, respectively. In a Cox univariate analysis, the size (P=0.04) and number of LMs (P<0.001), disease-free interval (P=0.04), curability of the initial LMs (P<0.001), and TVDT (P<0.001) were significantly identified as factors which affect prognosis. In the multivariate analysis, TVDT (P<0.001) and curability of the initial LMs (P<0.001) were confirmed as independent predictors of survival. There was a significant association between the number and curability of the initial LMs (P<0.001). In conclusion, metastasectomy and/or RFA of LMs is recommended for improving survival. However, TVDT and the curability of the LMs should be taken into consideration.

Radiofrequency Ablation Combined with Hepatic Arterial Chemoembolization Using Degradable Starch Microsphere Mixed with Mitomycin C for the Treatment of Liver Metastasis from Colorectal Cancer: A Prospective Multicenter Study.

PURPOSE: This phase II prospective study investigates possible benefits of radiofrequency ablation (RFA) combined with hepatic arterial chemoembolization using degradable starch microsphere (DSM) mixed with mitomycin C (MMC) in non-surgical candidates with colorectal liver metastases. MATERIALS AND METHODS: This study, approved by the respective institutional review board, included non-surgical candidates with 3 or fewer liver tumors of 3 cm or smaller, or a single lesion 5 cm or smaller. Percutaneous RFA was performed immediately after chemoembolization using DSM-MMC. Primary and secondary endpoints were the local tumor control rate, safety, and 2-year recurrence-free and overall survival rates. RESULTS: This study examined 25 patients (22 males, 3 females) with 38 tumors of mean maximum diameter of 2.2 ± 0.9 cm (standard deviation) (range 1.0-4.2 cm). Their mean age was 70.2 ± 8.2 years (range 55-82 years). Local tumor progression developed in 3 tumors (7.9%, 3/38) of 3 patients (12%, 3/25) during the mean follow-up of 34.9 ± 9.2 months (range 18.3-50.1 months). The 2-year local tumor control rates were 92.0% [95% confidence interval (CI), 81.4-100%] on a patient basis and 94.6% (95% CI, 87.3-100%) on a tumor basis. The respective 2-year overall and recurrence-free survival rates were 88.0% (95% CI, 75.3-98.5%) and 63.3% (95% CI, 44.2-82.5%), with median survival time of 48.4 months. Fever was the only adverse event requiring treatments in 2 patients (8%). CONCLUSIONS: This combination therapy is safe, exhibiting strong anticancer effects on colorectal liver metastasis, which might contribute to patient survival.

Clinical utility of radiofrequency ablation following transarterial injection of miriplatin-iodized oil suspension in small hepatocellular carcinoma.

PURPOSE: To retrospectively evaluate the clinical utility of radiofrequency ablation (RFA) following transarterial injection of miriplatin-iodized oil suspension (MPT-RFA) for hepatocellular carcinoma treatment. MATERIALS AND METHODS: We evaluated clinical outcomes of MPT-RFA for three or fewer hepatocellular carcinomas. Twenty-one patients with 30 tumors (maximum diameter: mean 1.4 ± 0.4 cm, range 0.7-2.2 cm) received MPT-RFA. RESULTS: Nineteen patients (90.5 %, 19/21) achieved complete ablation at the first RFA session. Two patients (9.5 %, 2/21) required a second RFA session but achieved complete ablation. Primary and secondary technical success rates were 90.5 and 100 %. There were no deaths related to the procedures performed. Grade 3 or 4 increases in the serum aspartate aminotransferase, alanine aminotransferase, and bilirubin levels were found in six patients (38.1 %, 8/21). There were no liver infarctions. During the median follow-up period of 24.1 months (mean ± SD 24.7 ± 6.9 months, range 13.8-38.9 months), the local tumor progression rate and overall survival rate at 2 years was 5.0 % (95 % confidence interval 0.3-20.6 %) and 86.7 % (95 % confidence interval 56.3-96.5 %), respectively. The mean hospital stay was 8.4 ± 3.1 days (range 5-18 days). CONCLUSION: MPT-RFA is a safe therapeutic option that initially provides therapeutic results.

Safety and Clinical Outcomes of Percutaneous Radiofrequency Ablation for Intermediate and Large Bone Tumors Using a Multiple-Electrode Switching System: A Phase II Clinical Study.

PURPOSE: To evaluate the safety and clinical outcomes of radiofrequency (RF) ablation using a multiple-electrode switching system in patients with bone tumors > 3 cm. MATERIALS AND METHODS: This prospective study enrolled 20 subjects (15 men, 5 women; mean age 70.0 y ± 7.4 [SD]; range, 60-80 y) with malignant unresectable bone tumors. The maximum mean tumor diameter was 5.5 cm ± 2.0 (range, 3.1-10.0 cm). Two to three RF electrodes were placed into each bone tumor. Real-time CT fluoroscopic guidance was used with a multiple-electrode switching system. The primary endpoint was safety, as evaluated by Common Terminology Criteria for Adverse Events, until 12 months after bone RF ablation. As secondary endpoints, pain relief was evaluated by visual analog scale (VAS) scores before and 1 week after RF ablation; tumor response, by contrast-enhanced magnetic resonance imaging studies until 4 weeks after bone RF ablation; and survival, by Kaplan-Meier method. RESULTS: No adverse event was found in 19 of 20 patients (95%). Grade 2 fever occurred in 1 patient (5%; 1/20). VAS scores decreased by ≥ 2 in 11 of 13 patients (84.6%) who had painful bone tumors. Tumor response (complete or partial response) was achieved in 16 of 18 patients (88.9%) who underwent follow-up imaging studies. The 1-year overall survival rate was 60.9%, and the median survival time was 14.1 months. CONCLUSIONS: Bone RF ablation using this system is safe and achieves local tumor control and pain relief in patients with large bone tumors.

False-Positive Tumor Enhancement After Cryoablation of Renal Cell Carcinoma: A Prospective Study.

OBJECTIVE: The objective of the present study was to prospectively evaluate the frequency of false-positive tumor enhancement after cryoablation of renal cell carcinoma (RCC). SUBJECTS AND METHODS: Patients who underwent cryoablation of a single RCC smaller than 7 cm were enrolled in the study. Contrast-enhanced MRI examinations were performed at five time points (2-3 days, 5-7 days, 1 month, 3 months, and 6 months) after cryoablation. For patients with completely ablated RCCs, the frequency and patterns of false-positive tumor enhancement and the risk factors associated with such enhancement were evaluated at each time point. RESULTS: The planned protocol was completed by 30 of the 33 enrolled patients (90.9%) with 30 RCCs (mean [± SD] size, 23.0 ± 8.7 cm; range, 1.0-4.7 cm). Complete tumor ablation was achieved for 25 RCCs (83.3%). Residual tumors were found in association with the other five RCCs (16.7%). Of the 25 completely ablated RCCs, false-positive tumor enhancement was observed for 15 tumors (60.0%) at 2-3 days after cryoablation; it continued to be observed for 13 tumors (52.0%) at 5-7 days and for one tumor (4.0%) at 1 month after cryoablation. The rate of false-positive tumor enhancement noted at 5-7 days after cryoablation was statistically significantly higher for clear cell RCCs (63.2%; 12/19) than for other RCC subtypes (16.7%; 1/6; p < 0.05). CONCLUSION: False-positive tumor enhancement frequently continues to be observed, particularly in clear cell RCCs, until 1 month after cryoablation of RCCs.

Long-Term Results of Stent Placement in Patients with Outflow Block After Living-Donor-Liver Transplantation.

PURPOSE: To evaluate long-term results of stent placement retrospectively in patients with outflow block after living-donor-liver transplantation (LDLT). MATERIALS AND METHODS: For this institutional review board approved retrospective study conducted during 2002-2012, stents were placed in outflow veins in 15 patients (11.3%, 15/133) (12 men; 3 female) in whom outflow block developed after LDLT. Their mean age was 52.3 years ± 15.3 (SD) (range, 4-69 years). Venous stenosis with a pressure gradient ≥5 mmHg (outflow block) was observed in the inferior vena cava in seven patients, hepatic vein in seven patients, and both in one patient. Technical success, change in a pressure gradient and clinical manifestations, and complications were evaluated. Overall survival of 15 patients undergoing outflow block stenting was compared with that of 116 patients without outflow block after LDLT. RESULTS: Stents were placed across the outflow block veins without complications, lowering the pressure gradient ≤ 3 mmHg in all patients (100%, 15/15). Clinical manifestations improved in 11 patients (73.3%, 11/15), and all were discharged from the hospital. However, they did not improve in the other 4 patients (26.7%, 4/15) who died in the hospital 1.0-3.7 months after stenting (mean, 2.0 ± 1.2 months). No significant difference in 5-year survival rates was found between patients with and without outflow block after LDLT (61.1 vs. 72.2%, p = .405). CONCLUSION: Stenting is a feasible, safe, and useful therapeutic option to resolve outflow block following LDLT, providing equal survival to that of patients without outflow block.

CT-Guided Percutaneous Cryoablation in Renal Cell Carcinoma: Factors Affecting Local Tumor Control.

PURPOSE: To retrospectively evaluate factors affecting local tumor control in cryoablation of renal cell carcinomas (RCCs). MATERIALS AND METHODS: This study examined 61 patients (43 men, 18 women) with a mean age of 69.1 years ± 10.8 (range 38-87 y) who underwent computed tomography (CT)-guided percutaneous cryoablation for a single RCC and were followed for 6 months or longer. Maximum tumor diameter was 0.8-4.8 cm (mean ± standard deviation, 2.4 ± 0.9 cm). Factors affecting local tumor control were evaluated. Deep tumor location was defined as the center side of the body perpendicular to the kidney midline. RESULTS: Median follow-up was 12.7 months. Residual unablated tumors and local tumor progression were observed after initial cryoablation in 4 patients each (13%, 8 of 61). All uncontrolled tumors were located in the deep side of the kidney (100%, 8 of 8), and were covered by an ice-ball margin of 5 mm or less. Deep tumor location (P = .005) and ice-ball margin (P = .002) were detected as significant factors affecting local tumor control on univariate analysis, and ice-ball margin remained significant in a stepwise logistic regression model (P = .006; odds ratio, 0.57; 95% confidence interval, 0.38-0.83). Complete tumor control rates were 42.9% (3 of 7), 92.6% (50 of 54), and 100% (20 of 20) with ice-ball margins of less than 3 mm, 3 mm or larger, and 6 mm or larger, respectively. CONCLUSIONS: Deep tumor location and ice-ball margins less than 6 mm were associated with incomplete local control following CT-guided percutaneous cryoablation for RCC.

Radiofrequency Ablation Using a Multiple-Electrode Switching System for Lung Tumors with 2.0-5.0-cm Maximum Diameter: Phase II Clinical Study.

PURPOSE: To prospectively evaluate the safety and effectiveness of radiofrequency ablation (RFA) by using a multiple-electrode switching system to treat 2.0-5.0-cm lung tumors. MATERIALS AND METHODS: The institutional review board approved this prospective phase II study. Written informed consent was obtained from all patients. Between September 2009 and July 2011, RFA using two or three radiofrequency (RF) electrodes and a multiple-electrode switching system was performed for malignant lung tumors with a maximum tumor diameter of 2.0-5.0 cm in nonsurgical candidates. The primary endpoint was safety, as evaluated using the Common Terminology Criteria for Adverse Events. Patients were observed for at least 1 year. Local tumor progression and overall survival were analyzed with the Kaplan-Meier method. RESULTS: Thirty-three patients (26 men, seven women; mean age, 70.5 years ± 10.0; age range, 46-87 years) with 35 lung tumors with a mean maximum diameter of 3.0 cm ± 0.7 (standard deviation; range, 2.0-4.4 cm) underwent treatment in 35 sessions. No procedure-related death or grade 4 adverse events (AEs) occurred. Grade 3 AEs occurred in four patients (12%), with pleural effusion requiring chest tube placement in two patients, pneumothorax requiring pleural adhesion in one patient, and pulmonary hemorrhage requiring pulmonary artery coil embolization in one patient. Grade 2 AEs were detected in 13 patients (39%). The 1-year local tumor progression and overall survival rates were 12.7% (95% confidence interval [CI]: 1.0, 25.5) and 81.2% (95% CI: 67.6, 94.8). CONCLUSION: RFA with a multiple-electrode switching system may be a safe therapeutic option with which to treat 2.0-5.0-cm lung cancer tumors.

Unresectable Adrenal Metastases: Clinical Outcomes of Radiofrequency Ablation.

PURPOSE: To retrospectively evaluate the clinical outcomes of radiofrequency (RF) ablation for the treatment of unresectable adrenal metastasis. MATERIALS AND METHODS: The institutional review board approved this retrospective study, and informed consent to perform adrenal RF ablation was obtained from all patients. From February 2005 through May 2014, 35 patients (25 men and 10 women; mean age, 64.7 years ± 9.6; age range, 39-82 years) underwent RF ablation to treat 41 metastatic adrenal tumors from lung cancer (n = 15), renal cell carcinoma (n = 9), colorectal cancer (n = 5), hepatocellular carcinoma (n = 4), and other tumors (n = 2). Tumors ranged in size from 1.2 to 8.2 cm (mean, 3.3 cm ± 1.6). The diagnosis was established mainly on the basis of radiologic findings. Adrenal arterial embolization was combined with RF ablation in 12 of the 35 patients (34%). Technical success, safety, local tumor progression, and survival were evaluated. The Kaplan-Meier method and Cox proportional hazard model were used to evaluate prognostic factors. RESULTS: There were 48 completed sessions with planned procedures and treatment protocols with no mortality and a major complication rate of 8.3% (four of 48 sessions). Tumor enhancement disappeared after initial adrenal RF ablation in 33 of the 35 patients (94%). Local tumor progression developed in eight of the 35 patients (23%); two patients received repeated RF ablation, resulting in adrenal tumor control in 27 of the 35 patients (77%) at the last follow-up (mean, 30.1 months ± 27.5; range 1.2-96.8 months). The 1-, 3-, and 5-year overall survival rates were 75% (95% confidence interval [CI], 61%, 90%), 34% (95% CI: 17%, 52%), and 30% (95% CI: 13%, 48%), respectively, with a median survival time of 26.0 months. Existence of extra-adrenal tumors (P = .005) and age of 65 years or older (P = .04) were significant indicators of a poor prognosis. CONCLUSION: Adrenal RF ablation is a feasible and useful method for controlling adrenal metastases and offers patients opportunities for improved survival.

Portal Venous Stent Placement for Malignant Portal Venous Stenosis or Occlusion: Who Benefits?

PURPOSE: The purpose of this study was to evaluate the efficacy of portal venous (PV) stent placement and find groups who benefit from this procedure among patients with symptomatic PV hypertension caused by malignant tumors. MATERIALS AND METHODS: From October 2001 to January 2013, 13 patients underwent PV stent placement because of PV stenosis or occlusion caused by bile duct cancer (n = 7), pancreatic cancer (n = 5), or nodal metastasis (n = 1). Technical success, changes in PV pressure gradient and palliative prognostic index (PPI) scores before and after stent placement, clinical outcomes, and complications were evaluated. RESULT: Stent was successfully placed in all patients (100 %, 13/13), lowering the mean PV pressure gradient from 12.4 ± 4.5 mmHg (range 5-20 mmHg) to 0.5 ± 0.9 mmHg (range 0-3 mmHg, p < 0.000001). Symptoms were improved in all but one patient (92.3%, 12/13). Although 10 patients (76.9%, 10/13) with pre-stent placement PPI scores lower than 6 (mean 3.5 ± 1.7, range 0-5) were discharged from the hospital, the other 3 with the pre-stent placement PPI of 6 or more (mean 7.2 ± 1.6, range 6-9.5) died within 4 weeks (range 17-28 days) without discharge. The median survival time of discharged patients was 123 days, and it was 20 days in non-discharged patients (p = 0.0001). A major procedure-related complication of intraperitoneal hemorrhage occurred in one patient (7.7%, 1/13). No significant factor was detected for the occurrence of complication. CONCLUSION: PV stent placement is a feasible, safe, and effective technique to relieve symptomatic PV hypertension caused by malignant tumors. The PPI score might be useful to stratify patients who benefit from this procedure.

Radiofrequency ablation after arterial injection of miriplatin-iodized oil suspension into swine liver: ablative zone size and tissue platinum concentration.

PURPOSE: To evaluate whether arterial injection of miriplatin-iodized oil suspension facilitates ablative zone expansion by radiofrequency (RF) ablation using a Cool-Tip electrode and to provide effective tissue platinum concentration in the normal swine liver. MATERIALS AND METHODS: RF ablation was performed at three sites of each liver. RF ablation alone was performed in two animals (control). Ablation was performed after arterial injection of iodized oil (iodized-oil group) or a miriplatin-iodized oil suspension (miriplatin group) in two animals each. Long- and short-axis diameters of the ablative zone were measured. In the miriplatin group, tissue platinum concentrations were measured in the ablative, surrounding hyperemic rim, and nonablative zones. RESULTS: The mean long- and short-axis diameters of ablative zones were 27.0 ± 3.1 and 18.0 ± 0.6 mm in the control. Although the long-axis diameter (30.2 ± 2.8 mm, p = 0.07) showed no significant expansion, the short-axis diameter (20.8 ± 2.6 mm, p = 0.04) was significantly expanded more in the iodized-oil group than in the control. Ablative zone sizes were largest in the miriplatin group. The long-axis diameter (33.5 ± 2.4 mm, p = 0.01) was significantly larger than that in the control. The short-axis diameter (27.2 ± 1.9 mm, p = 0.004) was significantly larger than that of the iodized-oil group. Tissue platinum concentrations showed an effective antitumor effect (≥9 µg/g) in ablative (16.5 ± 5.7 µg/g), surrounding hyperemic rim (18.0 ± 5.1 µg/g), and nonablative zones (mean 22.2 ± 5.7 µg/g) (p = 0.21). CONCLUSION: Arterial injection of miriplatin-iodized oil suspension can expand the ablative zone size and provide effective tissue platinum concentration on tumor control in the ablative zones and their surrounding hyperemic rim.