A case of adenoid cystic carcinoma presenting as Garcin's syndrome without mass formation.

Adenoid cystic carcinoma (ACC) is a malignant neoplasm that commonly arises in the major or minor salivary gland and usually forms mass lesions. Here, we report a case of ACC involving a 56-year-old man, who displayed right multiple cranial nerve palsies with ipsilateral severe facial pain but not any mass formation. Right submaxillary gland biopsy after repeated challenges at last revealed the primary focus of ACC with perineural invasion and without lymph node metastasis. The neurological manifestations were considered to be attributed to the perineural spread of ACC. It is extremely rare for ACC to show Garcin's syndrome without mass formation.