Protection from injury to organs adjacent to a renal tumor during Imaging-guided thermal ablation with hydrodissection and pyeloperfusion.

PURPOSE: The treatment of renal tumors is dictated by the results acquired from renal imaging, which play a crucial role in determining the appropriate strategy and surgical plan. Radiofrequency ablation, microwave ablation, and cryoablation are established percutaneous thermal ablation procedures that have widespread recognition. The objective of this scholarly article is to present a comprehensive summary of the application of the primary thermal protection strategies of the structures adjacent to renal tumors, in particular the effectiveness in terms of safety of hydrodissection and pyeloperfusion, in the context of percutaneous thermal ablation for renal tumors. METHODS: A literature search was conducted in PubMed in April 2023 using the keywords "hydrodissection", "hydrodisplacement", "renal", "kidney", "percutaneous ablation", "cryoablation", "microwave", "radiofrequency", and "pyeloperfusion". No language restriction was applied. RESULTS: Our study yielded a total of 676 cases describing the use of either hydrodissection or pyeloperfusion in conjunction with percutaneous thermal ablation. The fluids employed for displacing the neighboring structures encompassed saline solution, a mixture of saline solution and iodinated contrast, 5% dextrose in water, iodinated contrast in dextrose solution, lactated singer solution, and iodinated contrast. CONCLUSIONS: By using these procedures effectively, a greater number of ablations could be performed on anterior or lower polar renal tumors, sometimes excluded from these treatments due to the high risk of causing damage to adjacent anatomical structures.

Image-guided thermal ablation of central renal tumors with retrograde cold pyeloperfusion technique: a monocentric experience.

Purpose: To evaluate feasibility, safety and efficacy of image-guided thermal ablations associated with retrograde pyeloperfusion in patients with centrally located renal tumors.Materials and methods: 48 patients (15 women, 33 men, mean age 69.1 ± 11.8) were treated with image-guided thermal ablation associated with pyeloperfusion for 58 centrally located renal tumors (mean diameter 32.3 ± 7.32 mm). 7 patients had a single kidney. Microwave and radiofrequency ablation were used. All treatments were performed with ultrasound, CT, or fusion imaging guidance under general anesthesia and simultaneous retrograde cold pyeloperfusion technique.Results: Procedure was feasible in all cases. Technical success and primary technical efficacy were reached in 51/58 (88%) and 45/54 tumors (83%). With a second ablation performed in 5 tumors, secondary technical efficacy was achieved in 50/50 (100%) tumors. Minor and major complications occurred in 8/58 (13%) and 5/58 (8%) tumors. No significative change in renal function occurred after treatment.During follow-up, 5 recurrences occurred, that were retreated with a second ablation. At last follow up (mean 32.2 ± 22.0 months), 41/48 (85%) treated patients were free from disease. The median TTP and PFS were 27.0 (range, 2.3-80.0) and 26.5 months (range, 2.3-80.0), respectively.Conclusion: Image-guided thermal ablation associated with protective pyeloperfusion is a feasible, safe, and effective treatment option for patients with central renal tumors with a minimal impact on renal function and relevant potential to avoid nephrectomy.

Comparison of clinical outcome between pyeloperfused versus non-pyeloperfused microwave ablation of renal cell carcinoma.

PURPOSE: We present the outcomes of microwave ablation (MWA) of renal cell carcinoma (RCC) with and without pyeloperfusion. MATERIAL AND METHODS: A retrospective review of patients' records was undertaken to identify patients with RCC, who were treated with MWA with and without adjunctive pyeloperfusion. The distance between the tumour and ureter as well as the tumour size were measured on axial imaging. Pyeloperfusion was performed in nine patients in this series after placement of a ureteral stent and instilment of diluted contrast into the ureter. MWAs of the tumours were performed under computed tomography (CT) guidance. Hydrodissection was performed to displace at-risk organs. Creatinine was measured as renal function index after and before the procedure. A CT scan was performed at the end of the procedure and also after one, three, and six months, to identify the presence of residual disease and complications. RESULTS: Eighteen biopsies of proven RCC were treated with 20 sessions of MWA. The average follow-up time for this study was 180 days. The average distance between the ureter and the tumour in axial CT view was 20.8 (± 2.9) mm. Primary efficacy was achieved in 88% of pyeloperfused patients and in 100% of the non-pyeloperfused patients. Two pyeloperfused patients required secondary procedure, and full secondary efficacy was achieved for both. There was only one grade 2 urological complication, which occurred in a patient who underwent pyeloperfusion. Creatinine was not significantly different after the procedure in this study (p-value 0.4). CONCLUSION: In this study MWAs of RCCs were successfully performed using pyeloperfusion as a protective measure against thermal injury to the ureter.