Adenoid cystic carcinoma of the tongue base treated with ultrasound-guided interstitial photodynamic therapy: a case study.

Adenoid cystic carcinoma is a malignant neoplasm arising from the salivary glands. It accounts for 10-15% of all salivary gland neoplasms, representing 1-2% of malignant neoplasms of the head and neck. It is characterized by slow growth, diffuse invasion and potential to produce distant metastases, mainly to the lungs and bone. We present a case of adenoid cystic carcinoma of the base of tongue treated with ultrasound guided transcutaneous interstitial photodynamic therapy (PDT) as a salvage treatment.