The adjunctive diagnostic value of arterial spin labeling and depth of invasion in grading tongue cancers

Abstract Background Tongue cancer is a worldwide problem which has an increasing incidence. This study aimed to assess the relationship between tumor hemodynamic activity (tumor perfusion), quantified via ASL MRI, as well as clinical depth of invasion (DOI) in stratifying pathological grades of tongue carcinoma. Results A prospective analysis was done on thirty patients with tongue cancer who had undergone magnetic resonance imaging (MRI) with arterial spin labeling (ASL) study. The tumoral blood flow (TBF) of the tongue masses was assessed utilizing region of interest (ROI) alongside the clinical DOI measurement. These measurements were conducted independently by two observers. The lesions were classified according to pathological differentiation. The mean tumor blood flow (TBF) within malignant tongue lesions was quantified as 156.95 ± 45.66 mL/100 g/min. For histological grade differentiation, TBF thresholds demonstrated robust discriminatory capacity: a cutoff of more than 134.5 mL/100 g/min distinguished well-differentiated (G1) from moderately differentiated (G2) squamous cell carcinoma (SCC) (AUC = 1.0, p < 0.001), while a threshold of more than 178.5 mL/100 g/min differentiated G2 from poorly differentiated (G3) SCC (AUC = 1.0, p < 0.001). Clinical depth of invasion (DOI) similarly exhibited diagnostic utility in distinguishing G3 from lower-grade tumors, with a cutoff of more than 20 mm achieving perfect discriminative accuracy (AUC = 1.0, p < 0.001). However, DOI demonstrated limited efficacy in differentiating G1 from G2 tumors at a cutoff of more than 5.5 mm (AUC = 0.670, p = 0.272), reflecting its reduced sensitivity (75%) and specificity (57.1%) in this subgroup. Conclusion The ASL MRI is a noninvasive, non-contrast imaging tool that can differentiate and predict the pathological stages of tongue cancer.