MRI Accuracy to Predict Cutaneous Invasion of Oral Squamous Cell Carcinoma: A Radiological-Histological Comparison

Objective Cutaneous invasion in oral squamous cell carcinoma (OSCC) critically affects prognosis and surgical planning. While MRI is commonly used to evaluate tumor extension and depth of invasion (DOI), its accuracy in detecting cutaneous invasion is not well established. This study aimed to assess the reliability of MRI in detecting cutaneous invasion by comparing radiological and histopathological measurements. Study Design Thirty-five patients with advanced OSCC involving or approaching the skin underwent preoperative MRI and resection including the overlying skin. Tumor-to-skin distances on MRI were compared with histological distances. Results MRI identified all histologically confirmed cases of cutaneous invasion (sensitivity 100%), although 9 false-positive findings were observed. Compared with histopathology, MRI tended to underestimate the tumor–skin distance (mean bias−1.09 mm). The positive predictive value for frank cutaneous invasion (tumor–skin distance of 0 mm) was 61%. Conclusions MRI demonstrates high sensitivity and a high negative predictive value in detecting frank cutaneous invasion in OSCC; however, its moderate positive predictive value and underestimation of the tumor–skin distance indicate that imaging alone is insufficient to guide skin resection and should be integrated with clinical and intraoperative assessment.