The ending is not the end: Lymph node metastasis in oral squamous cell carcinoma

Lymph node metastasis is an important biological feature of oral squamous cell carcinoma, bearing poorly prognostic implications. However, the role of lymph node metastasis in cancer progression remains inconclusive. On the one hand, lymph nodes are pivotal sites for initiating specific immunity, which is crucial for maintaining antitumor immune response. On the other hand, they also serve as primary conduits for tumor metastasis, with lymph node colonization potentially inducing systemic immune dysfunction, thereby further promoting tumor progression. Considering this paradoxical role of lymph nodes, comprehending their impact on the primary tumor and immunity becomes paramount. Furthermore, leveraging these distinctive attributes of lymph nodes presents novel avenues for enhancing current therapeutic strategies against oral squamous cell carcinoma. This review summarizes the anatomical and molecular profiles of lymph node metastasis in oral squamous cell carcinoma, elucidating how lymphatic involvement compromises antitumor immunity, thus facilitating primary tumor and distant metastases. Additionally, it explores avenues for harnessing these mechanisms to optimize clinical interventions.