A machine learning model based on tumor-to-bone distance and radiomic features achieved an AUC of 0.88 for distinguishing intramuscular lipomas from well-differentiated liposarcomas, showing no significant difference compared to experienced radiologists.
Observational (n=68)
No
Does a machine learning model based on tumor-to-bone distance and radiomic features on MRI accurately distinguish intramuscular lipomas from well-differentiated liposarcomas compared to experienced radiologists?
A machine learning model using tumor-to-bone distance and radiomic features on T1-weighted MRI can distinguish intramuscular lipomas from well-differentiated liposarcomas with accuracy comparable to experienced musculoskeletal radiologists.
Absolute Event Rate: 0.88% vs 0.94%
p-value: p=>0.05
BACKGROUND: To develop a machine learning model based on tumor-to-bone distance and radiomic features derived from preoperative MRI images to distinguish intramuscular (IM) lipomas and atypical lipomatous tumors/well-differentiated liposarcomas (ALTs/WDLSs) and compared with radiologists. METHODS: The study included patients with IM lipomas and ALTs/WDLSs diagnosed between 2010 and 2022, and with MRI scans (sequence/field strength: T1-weighted (T1W) imaging at 1.5 or 3.0 Tesla MRI). Manual segmentation of tumors based on the three-dimensional T1W images was performed by two observers to appraise the intra- and interobserver variability. After radiomic features and tumor-to-bone distance were extracted, it was used to train a machine learning model to distinguish IM lipomas and ALTs/WDLSs. Both feature selection and classification steps were performed using Least Absolute Shrinkage and Selection Operator logistic regression. The performance of the classification model was assessed using a tenfold cross-validation strategy and subsequently evaluated using the receiver operating characteristic curve (ROC) analysis. The classification agreement of two experienced musculoskeletal (MSK) radiologists was assessed using the kappa statistics. The diagnosis accuracy of each radiologist was evaluated using the final pathological results as the gold standard. Additionally, we compared the performance of the model and two radiologists in terms of the area under the receiver operator characteristic curves (AUCs) using the Delong's test. RESULTS: There were 68 tumors (38 IM lipomas and 30 ALTs/WDLSs). The AUC of the machine learning model was 0.88 95% CI 0.72-1 (sensitivity, 91.6%; specificity, 85.7%; and accuracy, 89.0%). For Radiologist 1, the AUC was 0.94 95% CI 0.87-1 (sensitivity, 97.4%; specificity, 90.9%; and accuracy, 95.0%), and as to Radiologist 2, the AUC was 0.91 95% CI 0.83-0.99 (sensitivity, 100%; specificity, 81.8%; and accuracy, 93.3%). The classification agreement of the radiologists was 0.89 of kappa value (95% CI 0.76-1). Although the AUC of the model was lower than of two experienced MSK radiologists, there was no statistically significant difference between the model and two radiologists (all P > 0.05). CONCLUSIONS: The novel machine learning model based on tumor-to-bone distance and radiomic features is a noninvasive procedure that has the potential for distinguishing IM lipomas from ALTs/WDLSs. The predictive features that suggested malignancy were size, shape, depth, texture, histogram, and tumor-to-bone distance.
Sudjai et al. (Tue,) conducted a observational in Intramuscular lipomas and atypical lipomatous tumors/well-differentiated liposarcomas (n=68). Machine learning model based on tumor-to-bone distance and radiomic features vs. Experienced musculoskeletal radiologists was evaluated on Area under the receiver operating characteristic curve (AUC) for distinguishing IM lipomas from ALTs/WDLSs (95% CI 0.72-1, p=>0.05). A machine learning model based on tumor-to-bone distance and radiomic features achieved an AUC of 0.88 for distinguishing intramuscular lipomas from well-differentiated liposarcomas, showing no significant difference compared to experienced radiologists.