Radiologic–pathologic correlation of major versus minor extranodal extension in oral cavity cancer

Background To evaluate the diagnostic performance of radiologic extranodal extension (rENE) in predicting major (>2 mm) and minor (≤2 mm) pathologic ENE (pENE). Methods All oral cavity squamous cell carcinoma patients who underwent neck dissection with pathological nodal disease (pN+) between 2010 and 2015 were reviewed. Preoperative computed tomography and/or magnetic resonance imaging were reviewed by two head and neck neuroradiologists. Results Three hundred and thirty‐four patients were included. The sensitivity and specificity of rENE were 37% [95% CI 29–44] and 98% [95% CI 96–100], respectively. Sensitivity for pENE improved in the subset of patients with major ENE (48% [95% CI 38–57]). The presence of rENE was associated with inferior 3‐year overall survival: 26% [95% CI 17–41] versus 60% [95% CI 54–67]. Conclusions This large cohort study demonstrates high specificity, but low sensitivity for preoperative imaging in the detection of pENE in OCSCC. Patients with rENE demonstrated poor OS. pENE in the absence of rENE is still an adverse risk factor.