Preoperative MRI-based tumor volume or tumor thickness for tongue cancer: Which is more important?

Multiple studies have shown that tumor thickness (TT) or tumor volume (TV) play crucial roles in the diagnosis and treatment of tongue squamous cell carcinoma (TSCC). This study aimed to compare the application value of three-dimensional (3D) TV and TT based on preoperative magnetic resonance imaging (MRI) in forecasting cervical lymph node (CLN) metastases and the prognosis of TSCC.

A cohort of 81 patients was included in this study. ITK-SNAP and 3D Slicer software were used to determine 3D TV and TT. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the predictive accuracy of TT and TV for CLN metastasis and to identify the optimal cutoff values. Univariable and multivariable logistic regression analyses were used to identify factors associated with pathologically confirmed CLN metastasis. Overall survival was analyzed using the Kaplan-Meier method and Cox proportional hazards regression analysis. A nomogram was subsequently developed to provide individualized visual prediction of survival probability at specific time points.

The optimal cutoff values for predicting CLN metastasis were 13.5 mm for TT and 5.8 cm³ for TV. Multivariable analyses showed that TT ≥ 13.5 mm was independently associated with pathologically confirmed CLN metastasis and poorer overall survival in patients with TSCC, whereas TV did not retain independent significance. The nomogram incorporating tumor stage, pathological grade, and tumor thickness showed that TT contributed more to survival prediction than the other included clinicopathological variables. However, the small sample size and inaccurate initial T staging limit the reliability of the regression analysis and nomogram.