[Renal tumors percutaneous ablation by microwave. Initial experience.] / Ablación percutánea por microondas de tumores renales. Experiencia inicial.

OBJECTIVE: To analyze retrospectively the safety and effectiveness of percutaneous microwave ablation of solid renal tumors, and also review different approach techniques. METHODS: It is a retrospective study approved by the ethics committee of both hospitals. 14 tumors with a mean size of 37 mm (12-50 mm) were treated in a single session, under general anesthesia and with CT guidance, in 14 patients (9 men) with a mean age of 66 years, using the ablation system AMICA by different approaches (trans pulmonary, trans peritoneal and retroperitoneal). A biopsy was performed with a core needle to 13 of them prior to ablation in the same session. CT abdominal follow-up was performed (with and without i.v. contrast) at 1, 3, 6, 12, 18 and 24 months after ablation. Changes in serum creatinine levels pre- and post-ablation were also analyzed. RESULTS: The average follow-up time was 16.5 months (3-28 months) and we obtained complete response in 100% of the treated tumors. Only two minor complications were observed: one self-limited perirenal hemorrhage and one asymptomatic hydronephrosis, in the two patients to whom we did a transpulmonary approach, without pneumothorax in any of them. CONCLUSION: Percutaneous ablation of renal tumors seems to be a safe and effective technique, either via transpulmonary, transperitoneal or retroperitoneal approach, depending on tumor location. KEY POINTS: • Microwave ablation produces coagulation necrosis. • The sink effect is smaller in microwave ablation. • Microwave ablation seems to be safe and effective. • The type of approach is not correlated with major complications (Clavien > o =II).

Arterial Calcium Stimulation with Hepatic Venous Sampling in the Localization Diagnosis of Endogenous Hyperinsulinism.

Objective. The aim of this study was to assess the utility of arterial calcium stimulation with hepatic venous sampling (ASVS) in the localization diagnosis of endogenous hyperinsulinism. Patients and Methods. A retrospective descriptive study was performed including patients with endogenous hyperinsulinism who underwent ASVS. The histopathological diagnosis in patients who underwent a surgical procedure was used as the reference for the statistical study of the accuracy of this technique. Results. 30 patients were included with endogenous hyperinsulinism and nonconclusive imaging diagnosis was included. ASVS was performed in all cases. Surgery was performed in 20 cases. Insulinoma was removed in 19 patients; the location of all cases was detected in the ASVS. All cases of endogenous hyperinsulinism had a positive result for the ASVS, with this association being statistically significant (χ2 = 15.771; p < 0.001). A good and statistically significant agreement was obtained between histopathologic diagnosis and ASVS results (K = 0.518, p < 0.001). Conclusions. ASVS is a useful procedure in the localization diagnosis of endogenous hyperinsulinism undetected by other imaging tests. This technique allows the localization of intrapancreatic insulinomas and represents useful tool for the diagnosis and surgical management of these tumors.