Usefulness of post contrast three-dimensional fast field echo imaging compared with Dixon T2-weighted imaging for the evaluation of radiological depth of invasion in oral tongue squamous cell carcinoma: comparison with pathological depth of invasion assessment

Aim: Squamous cell carcinoma (SCC) is the most common malignancy that occurs within the oral cavity, with the tongue being the most frequent site affected. The depth of the carcinoma invasion has been demonstrated to be a predictor of cervical metastasis, recurrence, and disease-specific survival; depth of invasion (DOI) is also clinically used as a criterion for performance of elective neck dissection in early oral SCC. Both post-con-trast three-dimensional Fast Field Echo (3D-FFE) imaging and Dixon T2-weighted imaging (T2WI) may be useful to predict pathological DOI and can contribute to a successful treatment plan and patient prognosis. The purpose of this study was to evaluate the usefulness of post-contrast 3D-FFE imaging compared with Dixon T2WI for assessing radiological DOI, compared with pathological DOI, in oral tongue SCC. Methods: Twenty-two patients who have been diagnosed with tongue SCC were included in this study. The Wilcoxon singed-rank test was used to compare radiological DOI with pathological DOI, using both 3D-FFE imaging and DIXON T2WI. Results: The correlation coefficient between radiological DOI and pathological DOI using post-contrast 3D-FFE imaging was 0.79 ( p < 0.01). The correlation coefficient between radiological DOI and pathological DOI using Dixon T2WI was 0.72 ( p < 0.01). Conclusion: These data suggest that both post-contrast 3D-FFE imaging and DIXON T2WI may be useful in providing DOI estimations in oral tongue SCC; however, the post-con-trast 3D-FFE imaging may be a better imaging technique than Dixon T2WI for cases of oral tongue SCC.