Purpose:
Canalicular adenoma is a rare benign tumor arising almost exclusively within minor salivary glands of the oral cavity. We describe to our knowledge the first case of a canalicular adenoma of the lacrimal gland.
Methods:
Observational case report with review of clinical, radiographic and histologic features.
Results:
An 82 year-old woman presented with a two-month history of painless progressive right hypoglobus. Ophthalmic examination revealed 7 mm of right hypoglobus and 25% of normal supraduction of the right eye; the remainder of the examination was normal. MRI and CT images of the orbits revealed a large homogeneous lobular mass arising from the right lacrimal gland and extending to the superior orbit. Excisional biopsy of the mass was performed. Hematoxylin and eosin stained pathologic slides reveal a neoplasm with double rows of cells demonstrating a "beads-on-a-string" or "canaliculi" appearance, consistent with a canalicular adenoma of the lacrimal gland. (Figure 1).
Conclusions:
Canalicular adenoma is a benign slow growing tumor that accounts for less than 1% of the neoplasms of salivary gland origin. It arises purely from ductal luminal cells without evidence of stromal neoplasia, and is therefore sometimes referred to as "monomorphic adenoma." The most common site of involvement is in the salivary glands of the upper lip, followed by the buccal mucosa, palate, and rarely the parotid gland. The prognosis is excellent with complete surgical resection, although recurrence has been described in a small number of cases. There have been no reported cases of malignant transformation, systemic metastasis or tumor-related deaths. To our knowledge, this case represents the first reported case of a canalicular adenoma of the lacrimal gland.
Keywords: lacrimal gland • tumors • pathology: human