Lingual metastasis from primary pulmonary adenoid cystic carcinoma: A rare case report

Adenoid cystic carcinoma (AdCC) is a malignancy that most frequently originates in the salivary glands of the head and neck, though it may also rarely occur in other sites such as the trachea or breast. It is characterized by its slow-growing nature in the early stages, along with distinctive features of perineural invasion and a tendency for late metastasis, particularly to the lungs. Recurrence or metastasis can occur even years after the initial treatment. Currently, no standardized clinical protocol exists for long-term follow-up. The disease can recur or metastasize even years after initial treatment. At present, no uniform clinical protocol exists for long-term follow-up. To our knowledge, no documented cases of retrograde metastasis from primary pulmonary AdCC to the tongue have been reported. We describe the case of a male patient in his 40s with primary low-grade pulmonary AdCC who developed lingual metastasis after aggressive treatment. This case highlights an unusual metastatic pattern and underscores the need for vigilant, long-term monitoring of patients with AdCC.