Radiomic versus Convolutional Neural Networks Analysis for Classification of Contrast-enhancing Lesions at Multiparametric Breast MRI
Abstract
Convolutional neural networks were superior to radiomic analysis for classification of enhancing lesions. Although both approaches were inferior to radiologists’ performance, convolutional neural networks have the potential for further improvement with more training data whereas radiomic analysis does not.
Purpose
To compare the diagnostic performance of radiomic analysis (RA) and a convolutional neural network (CNN) to radiologists for classification of contrast agent–enhancing lesions as benign or malignant at multiparametric breast MRI.
Materials and Methods
Between August 2011 and August 2015, 447 patients with 1294 enhancing lesions (787 malignant, 507 benign; median size, 15 mm ± 20) were evaluated. Lesions were manually segmented by one breast radiologist. RA was performed by using L1 regularization and principal component analysis. CNN used a deep residual neural network with 34 layers. All algorithms were also retrained on half the number of lesions (n = 647). Machine interpretations were compared with prospective interpretations by three breast radiologists. Standard of reference was histologic analysis or follow-up. Areas under the receiver operating curve (AUCs) were used to compare diagnostic performance.
Results
CNN trained on the full cohort was superior to training on the half-size cohort (AUC, 0.88 vs 0.83, respectively; P = .01), but there was no difference for RA and L1 regularization (AUC, 0.81 vs 0.80, respectively; P = .76) or RA and principal component analysis (AUC, 0.78 vs 0.78, respectively; P = .93). By using the full cohort, CNN performance (AUC, 0.88; 95% confidence interval: 0.86, 0.89) was better than RA and L1 regularization (AUC, 0.81; 95% confidence interval: 0.79, 0.83; P < .001) and RA and principal component analysis (AUC, 0.78; 95% confidence interval: 0.76, 0.80; P < .001). However, CNN was inferior to breast radiologist interpretation (AUC, 0.98; 95% confidence interval: 0.96, 0.99; P < .001).
Conclusion
A convolutional neural network was superior to radiomic analysis for classification of enhancing lesions as benign or malignant at multiparametric breast MRI. Both approaches were inferior to radiologists’ performance; however, more training data will further improve performance of convolutional neural network, but not that of radiomics algorithms.
© RSNA, 2018
References
- 1. . Magnetic resonance imaging of the breast: recommendations from the EUSOMA working group. Eur J Cancer 2010;46(8):1296–1316.
- 2. . Radiomics: images are more than pictures, they are data. Radiology 2016;278(2):563–577.
- 3. . Decoding tumour phenotype by noninvasive imaging using a quantitative radiomics approach. Nat Commun 2014;5(1):4006.
- 4. . MR imaging radiomics signatures for predicting the risk of breast cancer recurrence as given by research versions of MammaPrint, Oncotype DX, and PAM50 gene assays. Radiology 2016;281(2):382–391.
- 5. . Large scale deep learning for computer aided detection of mammographic lesions. Med Image Anal 2017;35:303–312.
- 6. . Deep learning in mammography: diagnostic accuracy of a multipurpose image analysis software in the detection of breast cancer. Invest Radiol 2017;52(7):434–440.
- 7. . Prediction of malignancy by a radiomic signature from contrast agent-free diffusion MRI in suspicious breast lesions found on screening mammography. J Magn Reson Imaging 2017;46(2):604–616.
- 8. . Supplemental breast MR imaging screening of women with average risk of breast cancer. Radiology 2017;283(2):361–370.
- 9. . Python for scientific computing. Comput Sci Eng 2007;9(3):10–20.
- 10. . N4ITK: improved N3 bias correction. IEEE Trans Med Imaging 2010;29(6):1310–1320.
- 11. . Computational radiomics system to decode the radiographic phenotype. Cancer Res 2017;77(21):e104–e107.
- 12. . Transfer learning for breast cancer malignancy classification based on dynamic contrast-enhanced MR images. In: Maier A, Deserno T, Handels H, Maier-Hein K, Palm C, Tolxdorff T, eds. Bildverarbeitung für die Medizin 2018. Berlin, Germany: Springer, 2018; 216–221.
- 13. . Deep residual learning for image recognition. In: Proceedings of the IEEE Conference on Computer Vision and Pattern Recognition, Las Vegas, NV, June 27–30, 2016. Piscataway, NJ: Institute of Electrical and Electronics Engineers, 2016; 770–778.
- 14. . Imagenet large scale visual recognition challenge. Int J Comput Vis 2015;115(3):211–252.
- 15. . The meaning and use of the area under a receiver operating characteristic (ROC) curve. Radiology 1982;143(1):29–36.
- 16. . Deep learning as a tool for increased accuracy and efficiency of histopathological diagnosis. Sci Rep 2016;6(1):26286.
- 17. . Multiple hypothesis testing in genomics. Stat Med 2014;33(11):1946–1978.
- 18. . Screening with magnetic resonance imaging and mammography of a UK population at high familial risk of breast cancer: a prospective multicentre cohort study (MARIBS). Lancet 2005;365(9473):1769–1778 [Published correction appears in Lancet 2005;365(9474):1848.] https://doi.org/10.1016/S0140-6736(05)66481-1.
- 19. . Efficacy of MRI and mammography for breast-cancer screening in women with a familial or genetic predisposition. N Engl J Med 2004;351(5):427–437.
- 20. . Comparison of breast magnetic resonance imaging, mammography, and ultrasound for surveillance of women at high risk for hereditary breast cancer. J Clin Oncol 2001;19(15):3524–3531.
- 21. . Prospective multicenter cohort study to refine management recommendations for women at elevated familial risk of breast cancer: the EVA trial. J Clin Oncol 2010;28(9):1450–1457.
- 22. . Generative adversarial nets. In: NIPS’14: Proceedings of the 27th International Conference on Neural Information Processing Systems, Volume 2, Montreal, Canada, December 8–13, 2014. Cambridge, Mass: MIT Press, 2014; 2672–2680.
- 23. . Dermatologist-level classification of skin cancer with deep neural networks. Nature 2017;542(7639):115–118.
Article History
Received: June 9 2018Revision requested: July 26 2018
Revision received: Sept 25 2018
Accepted: Sept 26 2018
Published online: Nov 13 2018
Published in print: Feb 2019