Prospective evaluation of core number of biopsy for renal tumor: are multiple cores preferable?

PURPOSE: This single-center, single-arm, prospective, open-label study was conducted to evaluate the optimal number of cores (single or multiple) in renal tumor biopsy. MATERIALS AND METHODS: Forty-four biopsies of 44 tumors (mean diameter, 2.7 ± 1.0 cm; range, 1.6-5.0 cm) were included. Biopsy was performed under ultrasound or computed tomography fluoroscopy guidance using an 18-gauge cutting needle and the co-axial method. Two or more specimens were obtained, which were divided into first and subsequent specimens. "First specimen" and "all specimens" were histologically evaluated (i.e., appropriateness of specimen, histological diagnosis, subtype, and Fuhrman grade of renal cell carcinoma [RCC]) blindly and independently by two board-certified pathologists. RESULTS: Multiple specimens were successfully and safely obtained in all the biopsies. All tumors were histologically diagnosed; 40 malignancies included 39 RCCs and 1 solitary fibrous tumor, and 4 benign lesions included 2 angiomyolipomas, 1 oncocytoma, and 1 capillary hemangioma. In all RCCs, the subtype could be determined (32 clear cell RCCs, 4 chromophobe RCCs, and 3 papillary RCCs), and the Furman grade was determined in 38 RCCs. When only the first specimen was evaluated, 22.7% of the specimens were inappropriate for diagnosis, and 34 (77.3%) were histologically diagnosed. The diagnostic yield was significantly lower than that of all specimens (P = 0.0044). Univariate analysis revealed that smaller lesions were a significant predictor of diagnostic failure (P = 0.020). CONCLUSION: Biopsy with multiple cores significantly improved diagnostic yield. Thus, operators should obtain multiple cores during renal tumor biopsy.

Rituximab therapy for intractable pemphigus: A multicenter, open-label, single-arm, prospective study of 20 Japanese patients.

This was a multicenter clinical trial of rituximab, a chimeric monoclonal IgG antibody directed against CD20, for the treatment of refractory pemphigus vulgaris and pemphigus foliaceus. In total, 20 patients were treated with two doses of rituximab (1000 mg; 2 weeks apart) on days 0 and 14. The primary end point was the proportion of patients who achieved complete or partial remission on day 168 following the first rituximab dose. Of the 20 enrolled patients, 11 (55%) and four (20%) achieved complete and partial remission, respectively; therefore, remission was achieved in a total of 15 patients (75.0% [95% confidence interval, 50.9%-91.3%]). It was demonstrated that the remission rate was greater than the prespecified threshold (5%). In addition, a significant improvement in clinical score (Pemphigus Disease Area Index) and decrease in serum anti-desmoglein antibody level were observed over time. Four serious adverse events (heart failure, pneumonia, radial fracture, and osteonecrosis) were recorded in two patients, of which only pneumonia was considered causally related with rituximab. The level of peripheral blood CD19-positive B lymphocytes was decreased on day 28 after rituximab treatment and remained low throughout the study period until day 168. Our results confirm the efficacy and safety of rituximab therapy for refractory pemphigus in Japanese patients.

A single-center, single-arm, prospective, open-label trial to evaluate the efficacy and safety of percutaneous sclerotherapy with polidocanol for painful venous malformations (SCIRO-2001): study protocol.

This single-center, single-arm, prospective open-label trial is being conducted to evaluate the short-term efficacy and safety of percutaneous sclerotherapy with polidocanol foam for painful venous malformations. This study will include patients who were clinically diagnosed with venous malformation by using ultrasound and/or magnetic resonance imaging, and whose pain persisted even after treatment with medications. Written informed consent for sclerotherapy will be obtained from all patients. The institutional review board approved this prospective study protocol. The primary endpoint is pain relief at three months after sclerotherapy. Local pain related to venous malformation will be evaluated using a numeric rating scale. Patient recruitment commenced in December of 2020. Enrolment of 13 patients is planned over a 3-year recruitment period. Herein, we describe the details of the clinical trial protocol.

Percutaneous cryoablation combined with prior transcatheter arterial embolization for renal cell carcinomas of 3 cm or larger: a prospective study.

BACKGROUND: We prospectively evaluated the safety and efficacy of percutaneous cryoablation combined with transcatheter renal arterial embolization for the treatment of tumors ≥ 3 cm in diameter. METHODS: We included patients aged ≥ 20 years with histologically proven renal cell carcinoma with a tumor diameter ≥ 3 cm who were inoperable or refused surgery. Prior to ablation, transcatheter arterial embolization was performed using a mixture of absolute ethanol and iodized oil. All cryoablation procedures were performed percutaneously under computed tomography fluoroscopy guidance. The primary endpoint was safety, which was evaluated for adverse events using CTCAE version 4.0. The secondary endpoint was survival; overall survival, progression-free survival, and cancer-specific survival were calculated. RESULTS: From October 2013 to March 2016, 19 patients (mean age, 75 ± 13 years; 5 women, 14 men) were prospectively enrolled. The mean tumor diameter was 3.9 ± 0.7 (range 3.1-5.3) cm. Four grade 3 hematologic adverse events occurred, while no symptomatic grade ≥ 3 events occurred. The median follow-up period was 68 (range 52-84) months. During the follow-up period, two patients developed local tumor progression at 3 and 42 months after the initial ablative procedure; no patient showed distant metastasis. Two patients died from causes other than RCC. Overall survival, progression-free survival, and cause-specific survival were 100%, 95%, and 100% at 3 years, and 95%, 84%, and 100% at 5 years, respectively. CONCLUSION: Percutaneous cryoablation combined with prior TAE for the treatment of tumors ≥ 3 cm in diameter was safe and achieved favorable survival.

Early enlarging cavitation after percutaneous radiofrequency ablation of lung tumors: Incidence, risk factors and outcome.

PURPOSE: The purpose of this study was to retrospectively determine the incidence of early enlarging cavitation after percutaneous radiofrequency ablation (RFA) of lung tumor and identify risk factors associated with their occurrence. PATIENTS AND METHODS: A total of 245 patients (140 men, 105 women; mean age, 62.7 ± 11.8 [SD] years; age range: 31-87 years) with 605 lung tumors who were treated using 401 RFA sessions from April 2010 to March 2020 were included. Of which, 31 patients with 38 early enlarging cavitation and control group (151 patients with 228 tumors) were analyzed. Early enlarging cavitation was defined as cavities with an enlarged size (>3 cm) occurring on ablated lesions within seven days after RFA. Incidence of cavitation, risk and post-procedural factors of occurrence, major adverse events (AEs) that occurred in RFA sessions with cavitation, and course of cavitation were evaluated. AEs were classified using the CIRSE classification system for complications. RESULTS: Thirty-eight cavities (6.3%, 38/605 tumors) in 31 patients occurred in an average of 3.1 ± 1.7 days (range, 1-7 days) after 32 RFA sessions. Distance from pleura ≥ 20 mm, contact with vessel ≥ 3 mm, multitined expandable electrode ≥ 3 cm, and bronchus ≥ 2 mm encompassed in the ablation zone were independent risk factors of occurrence. Fever ≥ 38.5 °C, white blood cell count ≥ 10,000/µl one day after RFA, and steroid therapy were independent post-procedural factors of occurrence. Twenty-four Grade 3 and two Grade 6 AEs occurred. Twenty-nine cavities disappeared within a mean duration of 111.9 ± 64.9 (SD) days (range: 44-274 days) and four remained with a mean follow-up of 279.2 ± 174 (SD) days; five patients were lost to follow-up. CONCLUSIONS: Early enlarging cavitation occurs in 6.3% of lung tumors treated with RFA and are associated with 26 major AEs in 32 sessions. Aforementioned procedural factors and post-procedural inflammation were significant risk factors of occurrence.

Percutaneous needle biopsy under 1.2 Tesla open MRI guidance.

PURPOSE: To evaluate the feasibility of percutaneous needle biopsy using a 1.2 Tesla open magnetic resonance imaging (MRI) system, which has the highest field strength among the currently available open MRI systems. MATERIALS AND METHODS: This single-center prospective study included 10 patients. The primary endpoint was the feasibility of biopsy needle insertion into a target lesion under 1.2 Tesla open MRI guidance. The secondary endpoints included adverse events, device failures, and success of tissue specimen acquisition. Biopsy was performed for targets in various organs using an MRI-compatible coaxial needle system consisting of a 16G introducer needle and 18G semi-automatic biopsy needle. A newly developed body coil with a suitable design for intervention was used for intraprocedural imaging. RESULTS: Biopsy procedures were performed for six musculoskeletal masses, two retroperitoneal masses, one renal mass, and one liver mass. The median diameter of the targets was 4.9 cm (range 2.1-22.8 cm). MRI-guided biopsy needle insertion was feasible in all 10 patients. In total, four grade 1 adverse events (as per Common Terminology Criteria for Adverse Events version 4.0) occurred in three patients. Adequate biopsy specimens for pathological diagnosis were successfully obtained from all 10 patients. CONCLUSION: Percutaneous needle biopsy using a 1.2 Tesla open MRI system was feasible for relatively large targets, especially in the musculoskeletal region.

Survey Results and Recommendations from Japanese Stakeholders for Good Clinical Practice Renovation.

BACKGROUND: The International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH) is undertaking a major revision of ICH E6 Good Clinical Practice (GCP) decided to involve external stakeholders in ICH-GCP renovation. Activities such as surveys and public conferences have taken place in the United States, European Union, and Japan. For stakeholder engagement in Japan, a designated research group conducted a survey of academic stakeholders. METHODS: A total of 105 academic stakeholders from 18 institutions responded to the survey. The research group developed recommendations reflecting the survey results and the opinions from patients and the public. RESULTS: The survey showed the top four principles needing renovation were (i) informed consent (Chapter 2.9, 12.4% of respondents believed it needed renovation), (ii) systems for quality assurance (Chapter 2.13, 9.5%), (iii) information on an investigational product (Chapter 2.4, 5.7%), and (iv) procedures on clinical trial information (Chapter 2.10, 5.7%). The top three sections identified as needing renovation were: (i) informed consent (Chapter 4.8, 27.6%), (ii) monitoring (Chapter 5.18, 22.9%), and (iii) composition, functions, and operations of the ethics committee (Chapter 3.2, 14.3%). Recommendations included clarification of ICH-GCP's scope, proportionality in various aspects of clinical trials, diversity and liquidity of ethics committee members, modernization of informed consent procedures, variations in monitoring, and regulatory grade when using real-world data. CONCLUSION: The recommendations from Japanese investigators and patients have been submitted to the ICH E6 Expert Working Group, which will strengthen the robustness of the GCP renovation.

JME-001 phase II trial of first-line combination chemotherapy with cisplatin, pemetrexed, and nivolumab for unresectable malignant pleural mesothelioma.

BACKGROUND: JME-001 is a phase II trial assessing the efficacy and safety of cisplatin, pemetrexed, and nivolumab as first-line therapy in malignant pleural mesothelioma (MPM). PATIENTS AND METHODS: Patients with untreated, unresectable MPM with an Eastern Cooperative Oncology Group (ECOG) performance status (PS) of 0-1 were included. The primary endpoint is the centrally reviewed objective response rate. The secondary endpoints include (1) response rate assessed by investigators, (2) disease control rate, (3) overall survival, (4) progression-free survival, (5) duration of response, and (6) time to response. Safety and adverse events will also be evaluated. Cisplatin (75 mg/m2), pemetrexed (500 mg/m2), and nivolumab (360 mg/body) were administered intravenously every 3 weeks with a total of 4-6 cycles. If patients did not progress during the combination phase, maintenance therapy with nivolumab was administered until disease progression or unacceptable toxicity. Tissue samples were required and collected for programmed death ligand 1 analysis. RESULTS: Eighteen patients (mean age 69.2 years, 15 men) were enrolled between January 2018 and May 2019. The ECOG PS was 0 in 3 patients and 1 in 15 patients. Fourteen (77.8%; 95% CI 52.4% to 93.6%) patients had an objective response. The disease control rate was 94.4% (95% CI 72.7% to 99.9%). Fourteen (77.8%) patients had partial response (PR), three had stable disease, and one was not evaluable. Tumor shrinkage was observed in 10/14 (71.4%) patients with epithelioid, and 2/2 (100%) patients with sarcomatoid or biphasic histological subtype had PR. Ten (55.6%) patients experienced grade 3 or worse adverse events, including disorder of metabolism or nutrition (33.3%), loss of appetite (27.8%), anemia (16.7%), and hyponatremia (11.1%). No treatment-related deaths occurred. CONCLUSIONS: The safety and efficacy of this study strongly support a definitive trial of this combination.Trial registration numberUMIN000030892.

Study protocol for endoscopic ultrasonography-guided ethanol injection therapy for patients with pancreatic neuroendocrine neoplasm: a multicentre prospective study.

INTRODUCTION: The management of small pancreatic neuroendocrine neoplasms (PNENs) remains controversial. The standard treatment for PNENs is surgical resection; however, invasiveness of surgical procedure remains higher and the incidence of postoperative adverse events is still high. Recently, the efficacy and safety of endoscopic ultrasonography (EUS)-guided ethanol injection for small PNENs has been preliminarily demonstrated. Thus, a multicentre prospective study is being conducted to evaluate the efficacy and safety of EUS-guided ethanol injection therapy for small PNENs. METHODS AND ANALYSIS: The major eligibility criteria are the presence of pathologically diagnosed grade (G) 1 tumour, a tumour size of ≤15 mm and non-functional PNEN or insulinoma. For treatment, we will use a 25-gauge needle and pure ethanol. Contrast-enhanced CT (CE-CT) will be performed on postoperative day 3-5, and if enhanced areas of the tumour are still apparent, an additional session is scheduled during the same hospitalisation period. We set the total amount of ethanol per session to 2 mL. To evaluate the efficacy and safety, CE-CT will be performed at 1 and 6 months after treatment. The primary endpoint is the percentage of subjects who achieved all of the following evaluated points. Efficacy will be evaluated based on the achievement of complete ablation (defined as no enhanced area within the tumour on CE-CT) at 1 and 6 months. Safety will be evaluated based on the avoidance of severe adverse events within 1 month after treatment, continuing severe pancreatic fistula at 1 month after treatment and the incidence and/or exacerbation of diabetes mellitus at 6 months after treatment. ETHICS AND DISSEMINATION: This protocol has been approved by Okayama University Certified Review Board (approval number. CRB19-007). The results will be submitted to peer-reviewed journals and will be presented at international conferences. TRIAL REGISTRATION NUMBER: jRCTs061200016.

Percutaneous Cryoablation of Lower Limb Soft-Tissue Venous Malformations: Preliminary Results of Long-Term Efficacy.

PURPOSE: To retrospectively evaluate long-term efficacy of percutaneous cryoablation for lower limb soft-tissue venous malformations. MATERIALS AND METHODS: Nine patients (mean age, 36.6 years) with lower limb soft-tissue venous malformations were included. Cryoablation was performed percutaneously using an argon-based system. Adverse events (AE) using the Common Terminology Criteria for AEs version 4.0 were evaluated. The visual analog scale (VAS) scores and lesion volumes measured on magnetic resonance imaging were also evaluated at 12 months and 5-6 years. RESULTS: Technical success (i.e., complete coverage of the lesion by an iceball) was achieved in eight of the nine patients. All patients developed a total of 14 grade 1 or 2 adverse events. The mean (± standard deviation) VAS score was 6.0 (± 1.7) before therapy, whereas it was 0.14 (± 0.27) at 12 months and 0.97 (± 1.3) at 5-6 years (58-78 months). Complete pain relief was obtained in 6 and 5 patients at 12 months and 5-6 years, respectively. The median lesion volume was 2.49 mL before therapy, whereas it was 0.26 mL at 12 months and 0.35 mL at 5-6 years. CONCLUSION: Percutaneous cryoablation of lower limb soft-tissue venous malformations achieved considerable pain relief and lesion shrinkage for 5-6 years in this small preliminary study. LEVEL OF EVIDENCE: Level 4, Case Series.

Needle Tract Ablation in Liver Tissue Using a Cryoprobe Combined with an Electrosurgical Device: Influence of ex vivo and in vivo Animal Models.

To assess the feasibility of needle tract ablation in liver tissue in ex vivo and in vivo animal models using a cryo-probe and electrosurgical device. The experimental device is made by inserting a cryoprobe through an intro-ducer sheath for insulation, with 2-cm of probe tip projecting out. A beagle liver was punctured by the device, and electric current was applied at 30-W with the electrosurgical knife touching the non-insulated device base. The discolored area of cut surface along the device was evaluated in 5 application-time groups (5 , 10 , 15 , 20, or 25 seconds). An ex vivo experiment was performed to determine an ablation algorithm with an appropriate application time by comparison with radiofrequency ablation (RFA) results. Thereafter, an in vivo experiment was performed to verify the algorithm's feasibility. In the ex vivo model, the cut surface demonstrated different amounts of discolored area according to the application time. The total discolored area in the 20-seconds group was similar to that by RFA. In the in vivo model, the liver did not bleed, the total discolored area was similar to that ex vivo, and coagulation necrosis was confirmed by photomicrograph. Needle tract ablation can be per-formed using the experimental device and electrosurgical device.

Needle artifact characteristics and insertion accuracy using a 1.2T open MRI scanner: A phantom study.

PURPOSE: To evaluate the characteristics of needle artifacts and the accuracy of needle insertion using a 1.2 Tesla open magnetic resonance imaging (MRI) system in a phantom. MATERIALS AND METHODS: First, the apparent width of the needle on the MRI and the needle tip position error of 16- and 18-gauge MRI-compatible introducer needles and a 17-gauge cryoneedle were examined with different needle angles (0°, 30°, 45°, 60°, and 90°) to the main magnetic field (B0), sequence types (balanced steady-state acquisition with rewound gradient echo [BASG] and T2-weighted fast spin echo [FSE] sequence), and frequency encoding directions. Second, the accuracy of needle insertion was evaluated after 10 MRI fluoroscopy-guided insertions in a phantom. RESULTS: The apparent needle widths was larger when the angle of the needle axis relative to B0 was larger. The needles appeared larger on BASG than on T2-weighted FSE images, with the largest apparent widths of 16-, 17-, and 18-gauge needles of 14.3, 11.6, and 11.0mm, respectively. The apparent needle tip position was always more distal than the actual position on BASG images, with the largest longitudinal error of 4.0mm. Meanwhile, the 16- and 18-gauge needle tips appeared more proximal on T2-weighted FSE images with right-to-left frequency encoding direction. The mean accuracy of MRI fluoroscopy-guided needle insertion was 3.1mm. CONCLUSION: These experiments clarify the characteristics of needle artifacts in a 1.2 Tesla open MRI. With this system, the MRI fluoroscopy-guided needle insertion demonstrated an acceptable accuracy for clinical use.

Oncologic outcomes and safety of percutaneous cryoablation for biopsy-proven renal cell carcinoma up to 4 cm in diameter: a prospective observational study.

BACKGROUND: Percutaneous cryoablation is widely used for the treatment of renal cell carcinoma. We prospectively evaluated the oncologic outcomes and safety of percutaneous cryoablation for the treatment of tumors ≤ 4 cm in diameter. METHODS: We included patients aged ≥ 20 years, who had histologically proven renal cell carcinoma, tumor diameter ≤ 4 cm, a performance status of ≤ 1, acceptable laboratory parameters, were inoperable or refused to undergo surgery, and had signed a written informed consent. The primary endpoint was the cause-specific survival rate. The secondary endpoints were overall and progression-free survival, and adverse event frequency and grade. All procedures were percutaneously performed under computed tomography fluoroscopy guidance. RESULTS: From October 2013 to October 2015, 33 patients (mean age: 68 ± 14 years; sex: six women, 27 men) were enrolled. The mean tumor diameter was 2.1 ± 0.6 (range 1.0-3.4) cm. The median follow-up period was 60.1 (range 18.4-76.6) months. One patient died of non-renal cell carcinoma-related disease 46 months after percutaneous cryoablation. The cause-specific and overall survival rates were 100% and 96.8% at 3 years, and 100% and 96.8% at 5 years, respectively. There was no local tumor progression or distant metastasis. The incidence of severe urological (urinary fistula and perinephric infection) and non-urological adverse events (increased creatine kinase and skin ulceration) was 6% each. CONCLUSION: Percutaneous cryoablation for renal cell carcinoma ≤ 4 cm in diameter achieved good tumor control with a low complication frequency.

A Clinical Study Evaluating an Aspiration-type Semi-Automatic Cutting Biopsy Needle (SCIRO-1702).

An aspiration-type semi-automatic cutting biopsy needle enables tissue cutting during application of negative pressure, which is expected to contribute to a larger amount of specimen. The aim of the present study was to evaluate this novel needle in a clinical setting. Patients who underwent image-guided percutaneous biopsy for lung or renal masses were enrolled. Cutting biopsy was performed with and without aspiration during each procedure. The specimens were weighed using an electronic scale. The weights were compared between specimens obtained with and without aspiration using a paired t-test. The data from 45 lung and 30 renal biopsy procedures were analyzed. In lung biopsy, the mean±standard deviation weights of specimens obtained with and without aspiration were 2.20±1.05 mg and 2.24±1.08 mg, respectively. In renal biopsy, the mean weights were 6.52±2.18 mg and 6.42±1.62 mg, respectively. The weights were not significantly different between specimens obtained with and without aspiration either in lung (p=0.799) or renal (p=0.789) biopsies. The application of negative pressure with the aspiration-type semi-automatic cutting biopsy needle did not contribute to an increase in the amount of the specimen obtained in lung and renal biopsies.

Survival Outcomes of Treatment with Radiofrequency Ablation, Stereotactic Body Radiotherapy, or Sublobar Resection for Patients with Clinical Stage I Non-Small-Cell Lung Cancer: A Single-Center Evaluation.

PURPOSE: To retrospectively compare the outcomes of radiofrequency (RF) ablation, stereotactic body radiotherapy (SBRT), and sublobar resection (SLR) in patients with stage I non-small-cell lung cancer (NSCLC) at a single center. MATERIALS AND METHODS: Overall, 289 patients (38 RF ablation, 58 SBRT, and 193 SLR) were included. Kaplan-Meier curves were generated, multiple propensity score was estimated using a multinomial logistic regression model, and relationships between treatments and outcomes were assessed using a Cox proportional hazard model. Hazard ratios (HRs) for death from any cause and disease progression or death from any cause were examined by a crude model, an inverse probability of treatment weighting (IPTW) model, and an IPTW model adjusted for missing variables. RESULTS: The 5-year overall and progression-free survival rates were 58.9% and 39.9%, respectively, for RF ablation; 42.0% and 34.9%, respectively, for SBRT; and 85.5% and 75.9%, respectively, for SLR. Significantly longer survival time and lower HR were observed for SLR than other treatments. However, after statistical adjustment, these relationships were not significant except for reduced HR of disease progression or death from any cause of SLR compared to RF ablation in the IPTW model. The median hospital stays for RF ablation, SBRT, and SLR were 6.5, 6, and 16 days, respectively. Adverse events of grade 3 or higher occurred only in 11 SLR cases. CONCLUSIONS: SLR achieved the longest survival. However, after statistical adjustment, there were no significant outcome differences among RF ablation, SBRT, and SLR, except for 1 model. RF ablation or SBRT may be alternative treatments for selected patients with early-stage NSCLC.

Radiofrequency Ablation for Stage I Non-Small Cell Lung Cancer: An Updated Review of Literature from the Last Decade.

This review summarizes the current findings on radiofrequency ablation (RFA) for stage I non-small cell lung cancer (NSCLC) from relevant literature published in the last decade. While most earlier studies included small populations and had short follow-up periods, more robust data have become available owing to prospective or large cohort studies. The reported overall survival rates after RFA for stage I NSCLC were 83-96%, 40-74%, and 23-61% at 1, 3, and 5 years, respectively, in recent studies. Furthermore, many comparative studies on the outcomes of RFA and stereotactic body radiotherapy have been performed. Most of these studies report no significant difference in survival outcomes between the therapies. Currently, major guidelines define RFA as a reasonable alternative treatment for stage I NSCLC in non-surgical candidates.

Robotic needle insertion during computed tomography fluoroscopy-guided biopsy: prospective first-in-human feasibility trial.

INTRODUCTION: This was a prospective, first-in-human trial to evaluate the feasibility and safety of insertion of biopsy introducer needles with our robot during CT fluoroscopy-guided biopsy in humans. MATERIALS AND METHODS: Eligible patients were adults with a lesion ≥ 10 mm in an extremity or the trunk requiring pathological diagnosis with CT fluoroscopy-guided biopsy. Patients in whom at-risk structures were located within 10 mm of the scheduled needle tract were excluded. Ten patients (4 females and 6 males; mean [range] age, 72 [52-87] years) with lesions (mean [range] maximum diameter, 28 [14-52] mm) in the kidney (n = 4), lung (n = 3), mediastinum (n = 1), adrenal gland (n = 1), and muscle (n = 1) were enrolled. The biopsy procedure involved robotic insertion of a biopsy introducer needle followed by manual acquisition of specimens using a biopsy needle. The patients were followed up for 14 days. Feasibility was defined as the distance of ≤ 10 mm between needle tip after insertion and the nearest lesion edge on the CT fluoroscopic images. The safety of robotic insertion was evaluated on the basis of machine-related troubles and adverse events according to the Clavien-Dindo classification. RESULTS: Robotic insertion of the introducer needle was feasible in all patients, enabling pathological diagnosis. There was no machine-related trouble. A total of 11 adverse events occurred in 8 patients, including 10 grade I events and 1 grade IIIa event. CONCLUSION: Insertion of biopsy introducer needles with our robot was feasible at several locations in the human body. KEY POINTS: • Insertion of biopsy introducer needles with our robot during CT fluoroscopy-guided biopsy was feasible at several locations in the human body.

Robotic CT-guided out-of-plane needle insertion: comparison of angle accuracy with manual insertion in phantom and measurement of distance accuracy in animals.

OBJECTIVES: To evaluate the accuracy of robotic CT-guided out-of-plane needle insertion in phantom and animal experiments. METHODS: A robotic system (Zerobot), developed at our institution, was used for needle insertion. In the phantom experiment, 12 robotic needle insertions into a phantom at various angles in the XY and YZ planes were performed, and the same insertions were manually performed freehand, as well as guided by a smartphone application (SmartPuncture). Angle errors were compared between the robotic and smartphone-guided manual insertions using Student's t test. In the animal experiment, 6 robotic out-of-plane needle insertions toward targets of 1.0 mm in diameter placed in the kidneys and hip muscles of swine were performed, each with and without adjustment of needle orientation based on reconstructed CT images during insertion. Distance accuracy was calculated as the distance between the needle tip and the target center. RESULTS: In the phantom experiment, the mean angle errors of the robotic, freehand manual, and smartphone-guided manual insertions were 0.4°, 7.0°, and 3.7° in the XY plane and 0.6°, 6.3°, and 0.6° in the YZ plane, respectively. Robotic insertions in the XY plane were significantly (p < 0.001) more accurate than smartphone-guided insertions. In the animal experiment, the overall mean distance accuracy of robotic insertions with and without adjustment of needle orientation was 2.5 mm and 5.0 mm, respectively. CONCLUSION: Robotic CT-guided out-of-plane needle insertions were more accurate than smartphone-guided manual insertions in the phantom and were also accurate in the in vivo procedure, particularly with adjustment during insertion. KEY POINTS: • Out-of-plane needle insertions performed using our robot were more accurate than smartphone-guided manual insertions in the phantom experiment and were also accurate in the in vivo procedure. • In the phantom experiment, the mean angle errors of the robotic and smartphone-guided manual out-of-plane needle insertions were 0.4° and 3.7° in the XY plane (p < 0.001) and 0.6° and 0.6° in the YZ plane (p = 0.65), respectively. • In the animal experiment, the overall mean distance accuracies of the robotic out-of-plane needle insertions with and without adjustments of needle orientation during insertion were 2.5 mm and 5.0 mm, respectively.

Post-ablation syndrome after percutaneous cryoablation of small renal tumors: A prospective study of incidence, severity, duration, and effect on lifestyle.

PURPOSE: To prospectively investigate the incidence, severity, duration, and effect on lifestyle of post-ablation syndrome (PAS) after percutaneous renal cryoablation. MATERIALS AND METHODS: We enrolled 39 patients (27 male and 12 female; mean age, 62 years) who underwent 40 CT-guided cryoablation sessions for pathologically proven renal cancer (mean size, 20 mm) between December 2015 and December 2017. Four symptoms attributable to PAS, i.e., fever, nausea, vomiting, malaise, and the synergistic effect of these symptoms on lifestyle by 21 days after ablation were evaluated using a questionnaire. Symptoms were graded according to the common toxicity criteria of adverse events. RESULTS: The incidences of fever, nausea, vomiting, and malaise were 100% (40/40), 20% (8/40), 20% (8/40), and 63% (25/40), respectively. Most (78/81, 96%) symptoms had begun by day 2. The highest grade of fever per session was 0 (defined as ≥37.0 °C and <38.0 °C) (n = 24), 1 (n = 15), or 2 (n = 1); that of nausea was 2 (n = 8); that of vomiting was 1 (n = 7) or 3 (n = 1); and that of malaise was 1 (n = 14) or 2 (n = 11). Most (76/81, 94%) symptoms had resolved by day 8. The average values for the maximum scores of interference with general activity and work were 3.6 and 1.1, respectively. CONCLUSION: All symptoms were generally early-onset and self-limiting, with minimal impact on lifestyle and resolution by day 8. The clinical course and impact of PAS should be acknowledged by practitioners who manage patients undergoing renal cryoablation.

MRI-guided percutaneous needle biopsy with 1.2T open MRI: study protocol for a prospective feasibility study (SCIRO-1701).

There has been growing interest in magnetic resonance imaging (MRI)-guided interventional procedures such as percutaneous needle biopsy. Although open MRI is preferable for MRI-guided procedures in terms of patient accessibility, its inferior imaging capability due to lower field strength is a substantial limitation. In this situation, the high-field (1.2T) open MRI has recently become available. This novel MRI system is expected to provide excellent image quality as well as good patient accessibility, potentially contributing to safe and accurate device manipulation. This trial is designed to investigate the feasibility of MRI-guided percutaneous needle biopsy with this system. Patients with lesions needing percutaneous needle biopsy for pathological diagnosis are included. The enrollment of ten patients is intended. The primary endpoint of this study is the feasibility of biopsy needle insertion under real-time MR-fluoroscopy guidance based on the presence of the notch of the biopsy needle within the target lesion. The secondary endpoints are adverse events, device failures, and success of specimen acquisition. Once the feasibility of MRI-guided biopsy with 1.2T open MRI is validated by this study, it may potentially encourage widespread use of MRI-guidance for biopsy procedures. Furthermore, it may lead to development of the other MRI-guided interventional procedures using this MRI system.