Terminology and reporting criteria for radiofrequency ablation of tumors in the scientific literature: systematic review of compliance with reporting standards

Abstract

Objective: To perform a systematic review of compliance with standardized terminology and reporting criteria for radiofrequency (RF) tumor ablation, proposed by the International Working Group on Image-Guided Tumor Ablation in 2003, in the published reports.

Materials and methods: Literature search in the PubMed database was performed using index keywords, PubMed limit system, and eligibility criteria. The entire content of each article was reviewed to assess the terminology used for procedure terms, imaging findings, therapeutic efficacy, follow-up, and complications. Accuracy of the terminology and the use of alternative terms instead of standard terminology were analyzed. In addition, disparities in accuracy of terminology in articles according to the medical specialty and the type of radiology journal were evaluated.

Results: Among the articles (n = 308) included in this study, the accuracy of the terms 'procedure or session', 'treatment', 'index tumor', 'ablation zone', 'technical success', 'primary technique effectiveness rate', 'secondary technique effectiveness rate', 'local tumor progression', 'major complication', and 'minor complication' was 97% (298/307), 97% (291/300), 8% (25/307), 65% (103/159), 55% (52/94), 33% (42/129), 94% (17/18), 45% (88/195), 99% (79/80), and 100% (77/77), respectively. The overall accuracy of each term showed a tendency to improve over the years. The most commonly used alternative terms for 'technical success' and 'local tumor progression' were 'complete ablation' and 'local (tumor) recurrence', respectively. The accuracy of terminology in articles published in radiology journals was significantly greater than that of terminology in articles published in non-radiology journals, especially in Radiology and The Journal of Vascular and Interventional Radiology.

Conclusion: The proposal for standardization of terminology and reporting criteria for RF tumor ablation has been gaining support according to the recently published scientific reports, especially in the field of radiology. However, more work is still needed for the complete standardization of terminology.

Keywords: Ablation techniques; Neoplasms; Reference standards; Review; Terminology.

Fig. 1

Flow diagram showing process of selection of articles reviewed in this study. Systematic search of medical literature in PubMed database was performed in following three steps: index keywords, limit search system, and eligibility criteria. RF = radiofrequency ablation, MeSH = medical subject heading

Fig. 2

Overall trend for each terminology used in articles over years. Graph shows that most of terminologies used in each article maintain continuing stable trend over years. However, terms 'major complication' and 'minor complication' demonstrated increasing trend from 2004 to 2009, from 7% to 31% and from 7% to 30%, respectively.

Fig. 3

Overall accuracy of each term over years. As whole, accuracy of six terms tended to increase over years. This indicates that standardized terms recommended for reporting image-guided radiofrequency tumor ablation are gradually being used in more number of research studies. Accuracy of terms 'procedure or session', 'treatment', 'major complication', and 'minor complication' was maintained (at or near 100%) from 2004 to 2009. We excluded these four terms so that other results in figure would not be obscured. None of articles accurately used term 'index tumor' in 2004 and term 'secondary technique effectiveness rate' in 2004 and 2005.

Fig. 4

Comparison of overall accuracy of terminology in variety of situations. Graph shows significant difference in overall accuracy of terminology between articles published in radiology and non-radiology journals (59% vs. 35%, p = 0.01). Overall accuracy of terminology in articles published in Radiology and Journal of Vascular and Interventional Radiology was slightly superior to that of terminology in articles published in other radiology journals with statistical significance (67% vs. 54%, p = 0.02). P values were calculated using Fisher's exact test. JVIR = Journal of Vascular and Interventional Radiology

Fig. 5

Annual trend for accuracy of terminology in articles published in specific journals. Graph shows continuous increase in accuracy of investigated terms among articles published in both categories of journals from 2004 to 2009. However, there is significant difference in overall accuracy of terminology among articles published in both categories of journals, which may be due to editor's efforts for implementing proposed reporting standards. JVIR = Journal of Vascular and Interventional Radiology