Abstract
Response Evaluation Criteria In Solid Tumors (RECIST) is still the predominant criteria base for assessing tumor burden in oncology clinical trials. Despite several improvements that followed its first publication, RECIST continues to allow readers a lot of freedom in their evaluations. Notably in the selection of tumors at baseline. This subjectivity is the source of many suboptimal evaluations. When starting a baseline analysis, radiologists cannot always identify tumor malignancy with any certainty. Also, with RECIST, some findings can be deemed equivocal by radiologists with no confirmatory ground truth to rely on. In the specific case of Blinded Independent Central Review clinical trials with double reads using RECIST, the selection of equivocal tumors can have two major consequences: inter-reader variability and modified sensitivity of the therapeutic response. Apart from the main causes leading to the selection of an equivocal lesion, due to the uncertainty of the radiological characteristics or due to the censoring of on-site evaluations, several other situations can be described more precisely. These latter involve cases where an equivocal is selected as target or non-target lesions, the management of equivocal lymph nodes and the case of few target lesions. In all cases, awareness of the impact of selecting a non-malignant lesion will lead radiologists to make selections in the most rational way. Also, in clinical trials where the primary endpoint differs between phase 2 (response-related) and phase 3 (progression-related) trials, our impact analysis will help them to devise strategies for the management of equivocal lesions.
Highlights
Baseline oncologic evaluations are critical procedures as target selection determines the quality of the overall review
The goal of this paper is to provide insights for radiologists faced with equivocal baseline abnormalities and to raise awareness of the potential risks arising from such situations regarding the outcome of clinical trials using the Response Evaluation Criteria In Solid Tumors (RECIST) evaluation technique
Conclusion no studies have investigated the frequency of inclusion of equivocal lesions at baseline when applying RECIST, from radiologists’ experience, such inclusions are not uncommon
Summary
Baseline oncologic evaluations are critical procedures as target selection determines the quality of the overall review. The RECIST workgroup published a method and. In oncologic follow-up, equivocal lesions can be defined as lesions for which the radiologist is unsure whether they effectively correspond to the designated malignant disease. A given radiologic semiology is not specific to a single malignant etiology and some abnormalities may be artifactual or linked to transient nonmalignant disease (e.g., adverse effect, inflammation). Radiologists might, or might not, include equivocal lesions in their initial RECIST pool of lesions. We define these two approaches used by Iannessi et al Insights Imaging (2021) 12:36 radiologists as non-conservative and conservative, respectively.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
