Bilateral canalicular adenomas of the upper lip.

An unusual case of canalicular adenomas appearing bilaterally and simultaneously as separate nodules of the right and left upper lip is described. Upon histological examination, both nodules revealed tumor islands within their respective capsules, as well as outside their capsules and extending into normal salivary gland tissues. The article describes this unusual case and reviews the significance of the extracapsular tumor islands. The immunohistochemical profiles of canalicular adenoma and other salivary gland neoplasms with similar histology are compared and discussed.