Complete clinical response to chemoradiation in adenoid cystic carcinoma of the base of tongue: Case report of a rare tumor in a rare location.

Adenoid cystic carcinoma (ACC) is a rare tumor accounting for 1% of all head and neck cancers. The best treatment option is complete surgical resection with or without adjuvant radiotherapy. When surgical resection is not feasible, definitive radiotherapy with or without concurrent chemotherapy can be considered. Herein we report a non-smoker 72-year-old woman presented with throat discomfort and sensation of a lump. Evaluation revealed an unresectable adenoid cystic carcinoma of the base of tongue in whom complete clinical response was achieved after definitive concurrent chemoradiation. Although the cornerstone of treatment is complete surgical resection, this case report indicates that concurrent chemoradiotherapy might result in complete clinical response and could be used as a definitive treatment in selected ACC tumors.