Distant metastasis of oral squamous cell carcinoma: immune escape mechanism and new perspectives on treatment

Oral squamous cell carcinoma (OSCC) is frequently observed as the predominant malignancy affecting the oral cavity, with distant metastasis greatly affecting the treatment and long-term outlook for individuals with OSCC. Immune checkpoint inhibitors are a highly promising cancer treatment strategy currently available, but they are only successful for a small fraction of individuals with OSCC. Due to the insufficient understanding of the immune escape mechanisms in OSCC, coupled with disappointing treatment outcomes for patients with highly heterogeneous metastatic diseases, there is an urgent need for further exploration of immune target therapy strategies. This review discusses the mechanisms by which OSCC cells evade immune surveillance and attack, focusing on four aspects: metastasis-initiating cells, increased immune suppression, immune escape of dormant cells, and immune stromal crosstalk during metastasis. Additionally, we explore new areas in immune therapy for OSCC. In summary, our investigation offers fresh perspectives on the relationship between the tumor microenvironment and immune molecules, highlighting the importance of overcoming immune evasion for the development of novel therapies to manage OSCC metastasis and enhance patient outcomes.