Ablation Of Masses Research Articles

P193 Long term oncological outcomes following percutaneous microwave ablation of small renal masses

P193 Long term oncological outcomes following percutaneous microwave ablation of small renal masses

Factors that Affect Outcome of Ultrasound-Guided Radiofrequency Ablation of Renal Masses.

The purpose of this study was to examine the factors influencing the efficacy and safety of the ultrasound-guided radiofrequency ablation of renal tumors. Between January 2010 and December 2018, 159 patients with renal tumors treated with ultrasound-guided percutaneous radiofrequency ablation at our institution were included in this study. Biopsies were performed for histopathological analysis prior to each ablation. Patients underwent computed tomography follow-ups at 3, 6, and 12 months and were subsequently observed on an annual basis. The primary efficacy rate (i.e., residual tumor), local tumor progression, morbidity and mortality, and possible outcome predictors (age, body mass index, gender, tumor size, tumor location, tumor characteristics, ablation temperature, and reported technical problems) were analyzed using binary logistic regression. At the first follow-up, 3 months after ablation, the primary efficacy rate was 79%. Two percent of the tumors showed local tumor progression during the whole follow-up. Tumor proximity to the collecting system and the final temperature in the ablation region were associated with the occurrence of residual tumor (OR = 2.85, p = 0.019 and OR = 4.23, p = 0.006, respectively). A similar trend was shown for tumors larger than 3 cm (p = 0.066). A short distance to the collecting system and the ablation temperature were significantly related to the occurrence of residual tumors after the radiofrequency ablation of small renal masses. The ultrasound guidance used in our study has a lower primary efficacy rate than the computed tomography guidance used in comparable studies.

Dielectric characterisation of human adrenal glands and adrenal tumours for the development of microwave ablation technologies for hypertension treatment

Adrenal gland-induced hypertension results from underlying adrenal gland disorders including Conn’s syndrome, Cushing's syndrome, and Pheochromocytoma. These adrenal disorders are a risk for cardiovascular and renal morbidity and mortality. Clinically, treatment for adrenal gland-induced hypertension involves a pharmaceutical or surgical approach. The former presents very significant side effects whereas the latter can be ineffective in cases where the adrenal disorder reoccurs in the remaining contralateral adrenal gland. Due to the limitations of existing treatment methods, minimally invasive treatment options like microwave ablation (MWA) have received significant attention for treating adrenal gland disorders. A precise comprehension of the dielectric properties of human adrenal glands will help to tailor energy delivery for MWA therapy, thus offering the potential to optimise treatments and minimise damage to surrounding tissues. This study reports the ex vivo dielectric properties of human adrenal glands, including the cortex, medulla, capsule, and tumours, based on the data obtained from four patients (diagnosed with Conn’s syndrome, Cushing's syndrome, and Pheochromocytoma) who underwent unilateral adrenalectomy at the University Hospital Galway, Ireland. An open-ended coaxial probe measurement technique was used to measure the dielectric properties for a frequency range of 0.5–8.5 GHz. The dielectric properties were fitted using a two-pole Debye model, and a weighted least squares method was employed to optimise the model parameters. Moreover, the dielectric properties of adrenal tissues and tumours were compared across frequencies commonly used in MWA, including 915 MHz, 2.45 GHz, and 5.8 GHz. The study found that the dielectric properties of adrenal tumours were influenced by the presence of lipid-rich adenomas, and the dielectric properties of Cushing's syndrome tumour were lowest in comparison to the tumours in patients diagnosed with Conn's syndrome and Pheochromocytoma. Furthermore, a notable difference was observed in the dielectric properties of the medulla and cortex among patients diagnosed with Conn's syndrome, Cushing's syndrome, and Pheochromocytoma. These findings have significant implications for the diagnosis and treatment of adrenal tumours, including the optimisation of MWA therapy for precise ablation of adrenal masses.

Image-Guided Ablation of Renal Masses: Challenges to Produce High-Quality Evidence and Future Directions.

Image-guided ablation (IGA) is a rapidly developing field in interventional oncology. There is some evidence suggesting IGA's non-inferiority compared with partial or radical nephrectomy for the treatment of small renal masses (SRM). However, these are mostly limited to retrospective cohort studies. This review article outlines the evidence comparing IGA to partial nephrectomy by collating the different survival measures and evaluates the challenges of producing clinical trials and high-quality evidence. The main challenges are due to the heterogeneity of SRM, patient selection bias, unstandardized endpoint and outcomes, and the lack of global practice standards. Despite the evidence thus far demonstrating that IGA stands as a non-inferior treatment modality for SRMs, exhibiting favorable short- and long-term outcomes, further robust research is needed to integrate ablation techniques into routine clinical practice with a multidisciplinary approach. There is emerging evidence that suggests randomized controlled trial in SRMs is possible, and technologies such as histotripsy as well as artificial intelligence are used in IGA.

Prospective Margin Estimates Predict Local Tumor Progression Following Microwave Ablation of Small Renal Masses.

To evaluate the relationship between prospectively generated ablative margin estimates and local tumor progression (LTP) among patients undergoing microwave ablation (MWA) of small renal masses (SRMs). Between 2017 and 2020, patients who underwent MWA for SRM were retrospectively identified. During each procedure, segmented kidney and tumor shapes were coregistered with intraprocedural helical CT images obtained after microwave antenna placement. Predicted ablation zone shape and size were then overlaid onto the resultant model, and a model-to-model distance algorithm was employed to calculate multiple ablative margin estimates. LTP was modeled as a function of each margin estimate by hazard regression. Models were evaluated using hazard ratios and Akaike information criterion. Receiver operating characteristic curve area under the curve was also estimated using Harrell's and Uno's C indices (HI and UI, respectively). One hundred and twenty-eight patients were evaluated (median age 72.1years). Mean tumor diameter was 2.4 ± 0.9cm. LTP was observed in nine (7%) patients. Analysis showed that decreased estimated margin size as measured by first quartile (Q1; 25th percentile), maximum, and average ablative margin metrics was significantly associated with risk of LTP. For every one millimeter increase in Q1, maximum, and mean ablative margin, the hazard of LTP increased 67% (HR: 1.67; 95% CI = 1.25-2.20, UI = 0.93, HI = 0.77), 32% (HR: 1.32; 95% CI 1.09-1.60; UI = 0.93; HI = 0.76), and 48% (HR: 1.48; 95% CI 1.18-1.85; UI = 0.83; HI = 0.75), respectively. Prospectively generated ablative margin estimates can be used to predict the risk of local tumor progression following microwave ablation of small renal masses. LEVEL OF EVIDENCE 3: Retrospective cohort study.

Percutaneous Ablation of T1 Renal Masses: Comparative Local Control and Complications after Radiofrequency and Cryoablation.

The efficacy and complication rates of percutaneous radiofrequency ablation (RFA) and cryoablation (CA) in the treatment of T1 renal masses in two Northern Italy hospitals were retrospectively investigated. Eighty-two patients with 80 T1a tumors and 10 T1b tumors treated with thermal ablation from 2015 through 2020 were included. A total of 43 tumors in 38 patients were treated with RFA (2.3 ± 0.9 cm), and 47 tumors in 44 patients were treated with CA (2.1 ± 0.8 cm). The mean follow-up observation period was 26 ± 19 months. The major complications and efficacy, as measured using the technical success and local tumor recurrence rates, were recorded. There were three (6.9%) technical failures with RFA and one (2.1%) with cryoablation (p = 0.30). Among the 40 tumors that were successfully treated with RFA, 1 tumor (2.5%) developed local tumor recurrence; 5/46 tumors that were treated with cryoablation (10.8%) developed local tumor recurrence (p = 0.17). T1b lesions (4.0 ± 0.7 cm) resulted in 1/6 technically unsuccessful cases with RFA and 0/4 with CA. No recurrent disease was detected in the T1b lesions. Major complications occurred after 2.3% (1/43) of RFAs and 0/47 of cryoablation procedures. RFA and cryoablation are both effective in the treatment of renal masses. Major complications with either procedure are uncommon.

Oral 21 - Long term oncologic and procedural outcomes following percutaneous microwave ablation of small renal masses

Oral 21 - Long term oncologic and procedural outcomes following percutaneous microwave ablation of small renal masses

MP58-04 PROPOSAL AND INTERNAL VALIDATION OF A NOMOGRAM FOR THE PREDICTION OF LOCAL RECURRENCE FREE-SURVIVAL AFTER PERCUTANEOUS ABLATION FOR CT1 RENAL MASSES

MP58-04 PROPOSAL AND INTERNAL VALIDATION OF A NOMOGRAM FOR THE PREDICTION OF LOCAL RECURRENCE FREE-SURVIVAL AFTER PERCUTANEOUS ABLATION FOR CT1 RENAL MASSES

Abstract No. 553 Outcomes of Percutaneous Ablation of Synchronous and Metachronous Small Renal Masses (SRM)

Abstract No. 553 Outcomes of Percutaneous Ablation of Synchronous and Metachronous Small Renal Masses (SRM)

Percutaneous Microwave Ablation is Comparable to Cryoablation for the Treatment of T1a Renal Masses: Results From a Cross-Sectional Study.

Percutaneous microwave ablation (MWA) of renal masses (RM) is still considered experimental as opposed to established procedures such as cryoablation (CA). We aimed to compare perioperative, functional and oncological outcomes of patients with RM treated with CA and MWA. Data from 116 (69.9%) and 50 (30.1%) patients treated with CA and MWA for RM were analyzed. Patients' demographics and perioperative data were collected including nephrometry scores, complications, pre- and postprocedural renal function. Tumor persistence and recurrence were recorded. Descriptive statistics compared functional outcomes between groups. Cox regression analyses tested risk factors associated with recurrence. Groups were similar in terms of RM diameter, nephrometry scores and histology distribution. Median follow-up was 26 (13-46) and 24 (14-36) months for CA and MWA, respectively. The rate of overall (36.2% for CA vs. 24% for MWA, P= .1) and major (Clavien ≥ 3a) complications (1.7% vs. 5.4%, P=.1) were similar among groups. The median decline of renal function after 6 months follow-up did not differ between CA and MWA (P=.8). Tumor persistence [4.3% vs. 12%] and recurrence [9.5% and 7.1%] rates were similar for CA and MWA. Three years recurrence free and overall survival were 91% versus 95% (log-rank P=.77) and 80 versus 88% (log-rank P=.23) in the CA and MWA groups, respectively. At Cox analysis no predictors were found associated with recurrence. Despite being considered still experimental, MWA showed comparable outcomes relative to CA in terms of safety, preservation of renal function and oncological efficacy.

P118 - The impact of histology and type of energy used on oncological outcomes after local tumor ablation of small renal masses

P118 - The impact of histology and type of energy used on oncological outcomes after local tumor ablation of small renal masses

P112 - A new nephrometry score developed for percutaneous microwave ablation of renal masses

P112 - A new nephrometry score developed for percutaneous microwave ablation of renal masses

P098 - Development of BIFECTA: A surgical success score for percutaneous microwave ablation of renal masses and validation of PADUA, SPARE and R.E.N.A.L. nephrometry scores

P098 - Development of BIFECTA: A surgical success score for percutaneous microwave ablation of renal masses and validation of PADUA, SPARE and R.E.N.A.L. nephrometry scores

SC292 - The impact of histology and type of energy used on oncological outcomes after local tumor ablation of small renal masses

SC292 - The impact of histology and type of energy used on oncological outcomes after local tumor ablation of small renal masses

SC282 - Developing of a novel nephrometry score to predict the outcomes of percutaneous ablation of renal masses

SC282 - Developing of a novel nephrometry score to predict the outcomes of percutaneous ablation of renal masses

Abstract No. 60 Treatment margins and local tumor progression following thermal ablation of small renal masses

Prior work on image-guided thermal ablation (IGTA) of colorectal cancer liver metastases and hepatocellular carcinoma has demonstrated that ablation margin measurements correlate with treatment outcomes. How these measurements affect outcomes following renal mass ablation, however, remains unknown. This study assesses the relationship between treatment margins and local tumor progression (LTP) among patients with small renal masses (SRM) treated with IGTA.

Abstract No. 58 Combination, single-session selective transarterial embolization and microwave ablation for large renal masses: medium- to long-term follow-up

Single-session, same day, combined selective transarterial embolization and microwave ablation of large renal masses has been demonstrated to be safe and efficacious in the short-term. Herein we report the outcomes of patients treated with this novel therapeutic technique at a single academic medical center after five years of experience.

Applied Change Management in Interventional Radiology-Implementation of Percutaneous Thermal Ablation as an Additional Therapeutic Method for Small Renal Masses.

Interventional radiology (IR) has the potential to offer minimally invasive therapy. With this potential, new and arising IR methods may sometimes be in competition with established therapies. To introduce new methods, transformational processes are necessary. In organizations, structured methods of change management, such as the eight-step process of Kotter—(1) Establishing a sense of urgency, (2) Creating the guiding coalition, (3) Developing a vision and strategy, (4) Communicating the change vision, (5) Empowering employees for broad-based action, (6) Generating short-term wins, (7) Consolidating gains and producing more change, and (8) Anchoring new approaches in the culture—are applied based on considerable evidence. In this article, the application of Kotter’s model in the clinical context is shown through the structured transformational process of the organizational implementation of the percutaneous thermal ablation of small renal masses. This article is intended to familiarize readers in the medical field with the methods of structured transformational processes applicable to the clinical setting.

A0214 - Developing of a novel nephrometry score to predict the outcomes of percutaneous ablation of renal masses: The PCT score

A0214 - Developing of a novel nephrometry score to predict the outcomes of percutaneous ablation of renal masses: The PCT score

An Exploratory Analysis of Changes in Circulating Plasma Protein Profiles Following Image-Guided Ablation of Renal Tumours Provides Evidence for Effects on Multiple Biological Processes.

Further biological understanding of the immune and inflammatory responses following ablation is critical to the rational development of combination ablation-immunotherapies. Our pilot exploratory study evaluated the circulating plasma protein profiles after image-guided ablation (IGA) of small renal masses to determine the resultant systemic effects and provide insight into impact both on the tumour and immune system. Patients undergoing cryotherapy (CRYO), radiofrequency ablation (RFA) or microwave ablation (MWA) for small renal tumours were recruited. Blood samples were obtained at four timepoints; two baselines prior to IGA and at 24 h and 1-3 months post-IGA, and a panel of 164 proteins measured. Of 55 patients recruited, 35 underwent ablation (25 CRYO, 8 RFA, 2 MWA) and biomarker measurements. The most marked changes were 24 h post-CRYO, with 29 proteins increasing and 18 decreasing significantly, principally cytokines and proteins involved in regulating inflammation, danger-associated molecular patterns (DAMPs), cell proliferation, hypoxic response, apoptosis and migration. Intra-individual variation was low but inter-individual variation was apparent, for example all patients showed increases in IL-6 (1.7 to 29-fold) but only 50% in CD27. Functional annotation analysis highlighted immune/inflammation and cell proliferation/angiogenesis-related clusters, with interaction networks around IL-6, IL-10, VEGF-A and several chemokines. Increases in IL-8, IL-6, and CCL23 correlated with cryoprobe number (p = 0.01, rs = 0.546; p = 0.009, rs = 0.5515; p = 0.005, rs = 0.5873, respectively). This initial data provide further insights into ablation-induced biological changes of relevance in informing trial design of immunotherapies combined with ablation.