uu.seUppsala University Publications
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Predictive factors for complete renal tumor ablation using RFA
Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Urology.
Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Surgical Sciences, Radiology.
Show others and affiliations
2016 (English)In: Acta Radiologica, ISSN 0284-1851, E-ISSN 1600-0455, Vol. 57, no 7, p. 886-893Article in journal (Refereed) Published
Abstract [en]

BACKGROUND: Radiofrequency ablation (RFA) can be used to treat renal masses in patients where surgery is preferably avoided. As tumor size and location can affect ablation results, procedural planning needs to identify these factors to limit treatment to a single session and increase ablation success.

PURPOSE: To identify factors that may affect the primary efficacy of complete renal tumor ablation with radiofrequency after a single session.

MATERIAL AND METHODS: Percutaneous RFA (using an impedance based system) was performed using computed tomography (CT) guidance. Fifty-two renal tumors (in 44 patients) were retrospectively studied (median follow-up, 7 months). Data collection included patient demographics, tumor data (modified Renal Nephrometry Score, histopathological diagnosis), RFA treatment data (electrode placement), and follow-up results (tumor relapse). Data were analyzed through generalized estimating equations.

RESULTS: Primary efficacy rate was 83%. Predictors for complete ablation were optimal electrode placement (P = 0.002, OR = 16.67) and increasing distance to the collecting system (P = 0.02, OR = 1.18). Tumor size was not a predictor for complete ablation (median size, 24 mm; P = 0.069, OR = 0.47), but all tumors ≤2 cm were completely ablated. All papillary tumors and oncocytomas were completely ablated in a single session; the most common incompletely ablated tumor type was clear cell carcinoma (6 of 9).

CONCLUSION: Optimal electrode placement and a long distance from the collecting system are associated with an increased primary efficacy of renal tumor RFA. These variables need to be considered to increase primary ablation success. Further studies are needed to evaluate the effect of RFA on histopathologically different renal tumors.

Place, publisher, year, edition, pages
2016. Vol. 57, no 7, p. 886-893
Keywords [en]
Radiofrequency ablation (RFA); renal tumor; predict; ablation; radiofrequency; ablation success; complete ablation
National Category
Radiology, Nuclear Medicine and Medical Imaging
Identifiers
URN: urn:nbn:se:uu:diva-264586DOI: 10.1177/0284185115605681ISI: 000378051200020PubMedID: 26452975OAI: oai:DiVA.org:uu-264586DiVA, id: diva2:861051
Available from: 2015-10-15 Created: 2015-10-15 Last updated: 2019-09-04Bibliographically approved
In thesis
1. CT Guided Ablation of T1 Renal Tumors
Open this publication in new window or tab >>CT Guided Ablation of T1 Renal Tumors
2019 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

The widespread use of medical imaging contributes to the increased detection of incidentally detected small renal tumors, a majority which are often indolent masses found in elderly patients with preexisting chronic kidney disease. In Sweden, partial nephrectomy with minimal invasive surgical approach is the current standard for removing these tumors, although another option is percutaneous image-guided tumor ablation that allows treatment of elderly patients with comorbidities for who surgery is a risk. Due to the lack of long-term follow-up studies and prospective randomized trials, ablation is still considered an alternative option to surgery in Sweden. The aim of this thesis was to evaluate treatment of T1 renal tumors with CT guided radiofrequency (RFA) and microwave ablation (MWA).

Factors affecting the efficacy rate of complete tumor ablation with RFA after a single session were evaluated (Paper I). Optimal electrode placement and a long tumor distance to the collecting system were associated with an increased primary efficacy. Renal tumor RFA was compared with laparoscopic partial nephrectomy (LPN: Papers II-III): both methods had comparable secondary efficacy rates, but RFA involved several treatment sessions. Total session times and hospitalization times were shorter and complications less frequent for RFA than for LPN (Paper II). After treatment, renal function impact was assessed by evaluation of both renal function quantity and quality through determination of the split renal function (SRF: Paper III). Standard renal function measurements were assessed and both RFA and LPN were nephron sparing when treating small renal tumors and did not affect creatinine or GFR. However, LPN involved greater SRF reduction in the affected kidney than RFA. Initial experience with microwave ablation was evaluated and this new ablation technique demonstrated high efficacy rates with fewer complications, and was comparable with the mid-term results of now established ablation techniques (Paper IV).

In conclusion, CT guided RFA and MWA are safe and effective treatments for the removal of T1 renal tumors. This thesis provides further insights into the field of thermal ablation of small renal masses, which can aid future treatment selection and patient management.

Place, publisher, year, edition, pages
Uppsala: Acta Universitatis Upsaliensis, 2019. p. 71
Series
Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Medicine, ISSN 1651-6206 ; 1598
Keywords
Renal tumor, Ablation, Radiofrequency ablation, Microwave ablation
National Category
Radiology, Nuclear Medicine and Medical Imaging
Research subject
Radiology
Identifiers
urn:nbn:se:uu:diva-392318 (URN)978-91-513-0750-3 (ISBN)
Public defence
2019-11-01, Grönwallsalen, Akademiska sjukhuset, ingång 70, bv, Uppsala, 09:15 (Swedish)
Opponent
Supervisors
Available from: 2019-10-11 Created: 2019-09-04 Last updated: 2019-11-12

Open Access in DiVA

No full text in DiVA

Other links

Publisher's full textPubMed

Authority records BETA

Acosta Ruiz, VanessaLönnemark, MariaBrekkan, EinarDahlman, PärWernroth, LisaMagnusson, Anders

Search in DiVA

By author/editor
Acosta Ruiz, VanessaLönnemark, MariaBrekkan, EinarDahlman, PärWernroth, LisaMagnusson, Anders
By organisation
RadiologyUrologyUCR-Uppsala Clinical Research CenterMolecular epidemiology
In the same journal
Acta Radiologica
Radiology, Nuclear Medicine and Medical Imaging

Search outside of DiVA

GoogleGoogle Scholar

doi
pubmed
urn-nbn

Altmetric score

doi
pubmed
urn-nbn
Total: 1618 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf