Cervical Lymph Node Metastasis Patterns and Diagnostic Accuracy of Preoperative Staging in Oral Squamous Cell...

Background: Reliable assessment of cervical lymph node metastases remains a key challenge in the management of oral squamous cell carcinoma (OSCC). While elective ipsilateral neck dissection (ND) is widely accepted, the benefit of contralateral ND and the influence of tumor site on metastatic risk remain incompletely defined. This study aimed to evaluate patterns of lymphatic metastases, the diagnostic accuracy of preoperative staging, and the therapeutic relevance of ipsilateral and contralateral ND. Methods: A retrospective single-center cohort study was conducted including 287 patients with histologically confirmed OSCC treated between 2013 and 2019. Patterns of lymph node metastases were analyzed with respect to tumor localization and clinicopathological factors. Multivariate binary logistic regression was performed to identify predictors of cervical lymph node metastases. The diagnostic accuracy of preoperative staging was evaluated using histopathological findings as the reference standard. Results: Tumor localization and histopathological grading significantly influenced the occurrence of lymph node metastases. OSCC of the maxilla demonstrated a significantly lower observed rate of cervical and occult metastases compared with other tumor sites. Occult metastases were detected in 16.9% of primary tumor cases, with only two contralateral occult metastases observed. The calculated number needed to treat (NNT) was 6 for ipsilateral elective ND and 74 for contralateral elective ND. Preoperative staging showed limited diagnostic accuracy, with a negative predictive value of 0.83 and a positive predictive value of 0.65. Conclusions: Elective ipsilateral ND remains an essential component in the surgical management of OSCC due to the considerable rate of occult metastases and the limited reliability of preoperative staging. In contrast, the benefit of contralateral elective ND appears limited in patients without midline-crossing tumors. Maxillary OSCC and well-differentiated tumors demonstrated a significantly lower metastatic risk, supporting a more individualized risk-adapted approach to neck dissection in selected cases.