Hemangioma of the salivary gland: a study of ten cases of a rarely biopsied/excised lesion

Abstract

Hemangioma is a common soft tissue tumor that frequently occurs in the oral and maxillofacial region including salivary glands, but is rarely biopsied and is therefore often unfamiliar to the surgical pathologist. Our study examined the subclassification and histologic features of salivary gland hemangioma (SGH). Consultative cases coded as hemangioma and located in salivary gland from 1970 to 2000 were retrieved from the Registry of Oral and Maxillofacial Pathology of the Armed Forces Institute of Pathology (Washington, DC). Only cases with histologic evidence of salivary gland involvement were included. Slide material and patient history for all cases were reviewed, subclassification assigned, and histologic features were noted. Ten cases coded as hemangioma with slides and history met our inclusion criteria. Seven cases were the "juvenile hemangioma" subtype in the parotid of infants, ranging in age from 3 to 10 months (mean age, 5.3 months) with a male predominance. These SGH had a distinctive histologic appearance of a cellular proliferation of capillary sized vessels around retained salivary gland ducts. Mitoses were easily identified. Three additional cases in females included an arteriovenous hemangioma of a lip minor salivary gland since birth in a 15-month-old infant and two parotid gland lesions: a lobular capillary hemangioma of a 10-year-old and a cavernous hemangioma in a 51-year-old. The latter three cases grew as replacing masses and lacked retained salivary gland ducts within the lesion, despite glandular tissue at the periphery of the tumor. No SGH cases in our series were identified in the submandibular or sublingual glands. Despite its common occurrence, SGH is relatively rare in our surgical pathology files. The parotid gland is the most common location (90%). Salivary gland hemangioma includes usual hemangioma subtypes, mainly in females, and a distinctive infantile subtype of capillary hemangioma (juvenile hemangioma), displaying distinctive histology and found predominately in males. The cellularity, mitotic activity, and retained salivary gland ducts in the latter lesion should not make one consider malignancy.