“Real-world” radiomics from multi-vendor MRI: an original retrospective study on the prediction of nodal status and disease survival in breast cancer, as an exemplar to promote discussion of the wider issues

Cancer Imaging

Nicholas Turner¹  Mitch Dowsett²  Zaki Ahmed³  Elizabeth O’Flynn⁴  James d’Arcy⁵  Simon J. Doran⁵  Matthew Orton⁵  Santosh Kumar⁵  Fenna Kwaks⁵  Dow-Mu Koh⁶  Kate Downey⁶  Christina Messiou⁶ 

[1] Breast Cancer Now Toby Robins Research Centre, The Institute of Cancer Research, London, UK;Ralph Lauren Centre for Breast Cancer Research, Royal Marsden Hospital, London, UK;Centre for Molecular Pathology, Royal Marsden Hospital, London, UK;Breast Cancer Now Toby Robins Research Centre, The Institute of Cancer Research, London, UK;Department of Radiology, Royal Marsden Hospital, London, UK;Department of Radiology, St George’s Hospital, London, UK;Division of Radiotherapy and Imaging, Institute of Cancer Research, London, UK;Division of Radiotherapy and Imaging, Institute of Cancer Research, London, UK;Department of Radiology, Royal Marsden Hospital, London, UK;

关键词: Radiomics;    Nodal status;    Survival;    Multi-vendor;    Feature reduction;   

DOI  :  10.1186/s40644-021-00406-6

来源: Springer

【 摘 要 】

BackgroundMost MRI radiomics studies to date, even multi-centre ones, have used “pure” datasets deliberately accrued from single-vendor, single-field-strength scanners. This does not reflect aspirations for the ultimate generalisability of AI models. We therefore investigated the development of a radiomics signature from heterogeneous data originating on six different imaging platforms, for a breast cancer exemplar, in order to provide input into future discussions of the viability of radiomics in “real-world” scenarios where image data are not controlled by specific trial protocols but reflective of routine clinical practice.MethodsOne hundred fifty-six patients with pathologically proven breast cancer underwent multi-contrast MRI prior to neoadjuvant chemotherapy and/or surgery. From these, 92 patients were identified for whom T2-weighted, diffusion-weighted and contrast-enhanced T1-weighted sequences were available, as well as key clinicopathological variables. Regions-of-interest were drawn on the above image types and, from these, semantic and calculated radiomics features were derived. Classification models using a variety of methods, both with and without recursive feature elimination, were developed to predict pathological nodal status. Separately, we applied the same methods to analyse the information carried by the radiomic features regarding the originating scanner type and field strength. Repeated, ten-fold cross-validation was employed to verify the results. In parallel work, survival modelling was performed using random survival forests.ResultsPrediction of nodal status yielded mean cross-validated AUC values of 0.735 ± 0.15 (SD) for clinical variables alone, 0.673 ± 0.16 (SD) for radiomic features only, and 0.764 ± 0.16 (SD) for radiomics and clinical features together. Prediction of scanner platform from the radiomics features yielded extremely high values of AUC between 0.91 and 1 for the different classes examined indicating the presence of confounding features for the nodal status classification task. Survival analysis, gave out-of-bag prediction errors of 19.3% (clinical features only), 36.9–51.8% (radiomic features from different combinations of image contrasts), and 26.7–35.6% (clinical plus radiomics features).ConclusionsRadiomic classification models whose predictive ability was consistent with previous single-vendor, single-field strength studies have been obtained from multi-vendor, multi-field-strength data, despite clear confounding information being present. However, our sample size was too small to obtain useful survival modelling results.

【 授权许可】

CC BY