Abstract / Summary
Preoperative differentiation between pathological T3 (pT3) disease, representing locally advanced tumor confined to the larynx, and pathological T4 (pT4) disease, characterized by extension through the laryngeal cartilage and/or beyond the larynx, remains challenging in laryngeal squamous cell carcinoma (LSCC). This single-center retrospective study investigated the association between primary-tumor apparent diffusion coefficient (ADC) and pathological T stage and explored whether ADC could complement MRI-based morphological T classification. Twenty-eight patients with surgically confirmed, moderately differentiated LSCC were included (13 pT3 and 15 pT4). Mean ADC values were compared using the Mann–Whitney U test, and discrimination of pT4 disease was evaluated using receiver operating characteristic (ROC) analysis. Leave-one-out cross-validation was performed for internal validation of the ADC threshold and exploratory combined MRI–ADC rule. Mean ADC was significantly lower in pT4 than in pT3 tumors (760 ± 209 versus 1150 ± 188 × 10−6 mm2/s; p < 0.001). ADC achieved an area under the ROC curve of 0.913 (95% confidence interval, 0.769–1.000). The apparent combined MRI–ADC rule yielded a sensitivity of 93.3%, specificity of 100%, and overall accuracy of 96.4%. Under leave-one-out cross-validation, the corresponding estimates were 93.3%, 92.3%, and 92.9%, respectively. No statistically significant association between primary-tumor ADC and pathological nodal status was detected. Primary-tumor ADC was associated with pathological T stage and showed potential complementary value to morphological MRI; however, the threshold and combined rule remain hypothesis-generating and require independent external validation.