In carcinoma, base of tongue pain is referred to the ear through:

In carcinoma base of tongue pain is referred to the ipsilateral ear because of the common nerve supply of the base of tongue and ear i.e. Glossopharyngeal nerve. The anterior 2/3 of tongue is supplied by Lingual nerve Lingual nerve is a branch of mandibular N and auriculotemporal N which supplies ear is also a branch of mandibular N. Hence any pain of anterior 2/3 of tongue is referred to ear mandibular N. Any pain in the posterior 1/3 of tongue is referred to ear Glossopharyngeal and vagus N. Any pain in the base of tongue is referred to ear glossopharyngeal N.