Adenoid cystic carcinoma of palate: Report of a solid variant.

Adenoid cystic carcinomas (ADCCs) are uncommon tumors, comprising < 1% of all head-and-neck cancers and 20%-25% of all salivary cancers. The most common presenting symptom of the lesion is a slowly growing mass followed by pain due to the propensity of these tumors for perineural invasion. The tumor is most often clinically deceptive by its small size and slow growth, which actually overlies its extensive subclinical invasion and marked ability for early metastasis making the prognosis questionable, aptly referred as "wolf in sheep's clothing." Cribriform, tubular and solid are the three recognized histopathological patterns. In ADCC, one of the important prognostic factors is the histological grade determined by the percentage of solid component in the tumor, which in the present study comprise more than 30% of the entire lesion rendering it an unfavorable prognosis.