Perineural invasion is a type of metastatic tumor spread in which cancer cells travel along nerves far away from the primary lesion. Perineural invasion is linked to an increased risk of metastasis and a lower chance of survival in oral salivary gland cancer. The migration of cancer cells towards nerves necessitates the activation of numerous signaling pathways involving numerous growth factors. In many types of cancer, neurotrophins such as nerve growth factor and nerve growth factor receptors and molecules like neuropeptides such as galanin contribute to survival, proliferation, and migration signaling pathways.
