Hybrid Carcinoma Of Minor Salivary Gland: Report Of A Case Of Adenoid Cystic And Mucoepidermoid Carcinoma, An Unusual Combination

A 73 years-old Saudi male presented with an upper lip swelling. Incisional biopsy diagnosis was adenoid cystic carcinoma and total excision was recommended. On histopathological analysis of the excised lesion , a single mass comprising two well defined tumors, namely, adenoid cystic (20 %) and mucoepidermoid (80%) carcinomas was identified. These were lying adjacent to each other with a transitional zone in between . The final diagnosis was hybrid carcinoma of minor salivary gland origin. Hybrid salivary gland tumors are very rare and, to the best of our knowledge only two cases of hybrid adenoid cysticmucoepidermoid carcinoma have been previously reported. Synchronous or metachronous recognition of two components in a salivary gland tumor is practically important to both the pathologist and the clinician becoming particularly significant when the constituent entities have different biological behaviors. The more aggressive component modulates the line of treatment conferred upon the patient. Pathologists are, therefore, urged to rule out the presence of additional tumoral components in any given salivary gland tumor.