title: [What can/should be treated in kidney tumors and when].
abstract: OBJECTIVE
  In the treatment of localized renal cell carcinoma, the lack of randomization in controlled trials on thermal ablation is a major limitation. The latter leads to significant study bias and it ultimately remains unclear whether the improved overall survival in favor of partial nephrectomy can actually be attributed to the treatment method.
  
  
  METHODS
  For T1a (≤4 cm) renal cell carcinoma without lymph node and distant metastases, excellent technical and clinical results have been described after imaging-guided radiofrequency ablation and cryoablation.
  
  
  METHODS
  Low major complication rates, preservation of renal function and three-dimensional confirmation of negative ablation margins (A0 ablation) are the advantages of computed tomography (CT)-guided thermal ablation.
  
  
  METHODS
  According to the results of controlled (non-randomized) trials on T1a renal cell cancer, the cancer-specific survival rates are comparable between ablative and surgical techniques.
  
  
  RESULTS
  It is high time for prospective randomized controlled trials to define the actual value of percutaneous thermal ablation and partial nephrectomy in the treatment of T1a renal cell carcinoma.
  
  
  CONCLUSIONS
  Apart from localized renal cell carcinoma, angiomyolipoma and oncocytoma can be treated by thermal ablation. Transarterial embolization extends the radiological spectrum for the treatment of renal tumors, either as complementary embolization (e. g. before thermal ablation of T1a and T1b renal cell carcinoma), prophylactic embolization (e. g. angiomyolipoma >6 cm), preoperative embolization (e. g. before laparoscopic partial nephrectomy) or palliative embolization (e. g. in patients with symptomatic macrohematuria due to renal cell carcinoma).
authors.affiliation: Klinik für Diagnostische und Interventionelle Radiologie, Radiologische Klinik, Universitätsklinikum Heidelberg, Im Neuenheimer Feld 110, 69120, Heidelberg, Deutschland. christof.sommer@med.uni-heidelberg.de.|Klinik für Diagnostische und Interventionelle Radiologie, Klinikum Stuttgart, Katharinenhospital, Stuttgart, Deutschland. christof.sommer@med.uni-heidelberg.de.
authors.forename: C M
authors.initials: CM
authors.lastname: Sommer
authors.affiliation: Abteilung Neuroradiologie, Radiologische Klinik, Universitätsklinikum Heidelberg, Heidelberg, Deutschland.
authors.forename: D F
authors.initials: DF
authors.lastname: Vollherbst
authors.affiliation: Klinik für Diagnostische und Interventionelle Radiologie, Klinikum Stuttgart, Katharinenhospital, Stuttgart, Deutschland.
authors.forename: G M
authors.initials: GM
authors.lastname: Richter
authors.affiliation: Klinik für Diagnostische und Interventionelle Radiologie, Radiologische Klinik, Universitätsklinikum Heidelberg, Im Neuenheimer Feld 110, 69120, Heidelberg, Deutschland.
authors.forename: H U
authors.initials: HU
authors.lastname: Kauczor
authors.affiliation: Klinik für Radiologie, minimal-invasive Therapien und Nuklearmedizin, SLK-Kliniken Heilbronn GmbH, Heilbronn, Deutschland.
authors.forename: P L
authors.initials: PL
authors.lastname: Pereira
mesh_terms: D055011:Ablation Techniques / Q000706:statistics & numerical data*; D015982:Bias; D002292:Carcinoma, Renal Cell / Q000000981:diagnostic imaging / Q000453:epidemiology* / Q000601:surgery*; D019317:Evidence-Based Medicine; D006801:Humans; D007680:Kidney Neoplasms / Q000000981:diagnostic imaging / Q000453:epidemiology* / Q000601:surgery*; D009392:Nephrectomy / Q000706:statistics & numerical data*; D018579:Patient Selection; D015995:Prevalence; D011379:Prognosis; D012307:Risk Factors; D016896:Treatment Outcome
keywords: Cryoablation; Embolization; Partial nephrectomy; Radiofrequency ablation; Renal cell carcinoma