The aim of the study is the evaluation of the ablation efficiency of the percutaneous irreversible electroporation (IRE) as primary ablation therapy of locally confined renal cell carcinoma (≤4cm, see inclusion and exclusion criteria).

The ablation success will be proofed by magnet resonance imaging (MRI) and histologically after partial kidney resection or nephrectomy 4 weeks after IRE. Hypotheses: Kidney tumors ≤4cm can be ablated completely by percutaneous IRE. Surrounded structures and renal tissue can be preserved.

Health Condition or Problem studied:

1. International Statistical Classification of Diseases and Related Health Problems, Tenth Revision (ICD10): C64 - Malignant neoplasm of kidney, except renal pelvis
2. ICD10: D41.0 - Neoplasm of uncertain or unknown behaviour: Kidney

Interventions/Observational Groups Arm 1:

1. Initial diagnostical examination of the renal mass.
2. If any extended diagnostical examination for treatment planning.
3. Day -29 to -1: Recruitment.
4. Day -1: MRI of the kidney, Karnofsky, physical examination, blood chemistry, urosonography, if any renal scintigraphy, life quality assessment.
5. Day 0: Percutaneous diagnostical biopsy with histopathological investigation and therapeutically, CT- and/or ultrasound-guided, ECG-synchronized irreversible electroporation (IRE) of the kidney tumor in endotracheal anaesthesia und muscle relaxation. Use of 1-6 IRE probes with 90-100 pulses of 1500-3000 volts und 20-50 amperes each.
6. Day 1-7: Postinterventional follow-up: MRI of the kidneys, Karnofsky, physical examination, blood chemistry, urosonography, life quality assessment.
7. Day 27: Postinterventional follow-up: MRI of the kidneys, Karnofsky, physical examination, blood chemistry, urosonography, if any renal scintigraphy, life quality assessment.
8. Day 28: Open surgery partial kidney resection or tumor nephrectomy of the IRE treated kidney resp. kidney tumor region with histopathological investigation.
9. Day 29-37: Postoperative follow-up: physical examination, blood chemistry, urosonography, life quality assessment.
10. Day 112: Study-Follow-up: MRI of the kidneys, Karnofsky, physical examination, blood chemistry, urosonography, if any renal scintigraphy, life quality assessment. Termination of the study.
11. Study closed, Individual follow-up due to the European Association of Urology guideline.

Recruitment:

• (Anticipated or Actual) Date of First Enrollment: 2013/10/14
• Planned/Actual: Opened
• Target Sample Size: 20
• Monocentric/Multicentric trial: Monocentric trial
• National/International: National

Inclusion Criteria:

• one or more localized, resectable kidney tumors (≤4 cm) suspicious of malignancy or histology -proven renal cell cancer (RCC)
• patients desire for therapy and surgical therapy
• Karnofsky-index >70%
• Age ≥ 18 years
• life expectancy ≥ 12 month
• compliance of the patient taking part in a study
• informed consent

Exclusion Criteria:

• violation against one or more inclusion criteria
• cardial pacemaker or other electrical implants
• QT-interval >550 ms or cardiac arrhythmias or condition after myocardial infarction, that make an ECG-synchronisation unfeasible
• known cardial ejection fraction < 30% or NYHA III or III-IV
• known epilepsy
• second malignancy (except basal-cell carcinoma and cervical carcinoma in situ)
• immunosuppression or HIV-positive patients
• active infection or severe health interference, that make taking part in a study unfeasible
• pregnancy, lactation period, no contraception
• metastatic disease
• palliative status
• running or executed RCC therapy
• taking part in another clinical study for RCC
• inoperable
• rejection of interventional or surgical therapy by the patient
• circulatory instability
• general contraindications for anesthesia, endotracheal anesthesia and muscle relaxation
• psychiatric disorders that make taking part in a study or giving informed consent unfeasible
• haemorrhage, impossible intermission of taking blood thinner, untreatable thrombophilia
• thromboplastin time ≤50 %, thrombocytes ≤50 Gpt/L; partial thromboplastin time >50
• MRI incompatibility
• metal implants <1 cm closed to the kidney / kidney tumor
• contraindication for biopsy and punction of the renal tumor under CT-guidance
• untreated urinary retention
• renal pelvis tumor, suspected transitional cell cancer