Lacrimal Gland Disease & Tumors

Overview

The main lacrimal gland sits in the lacrimal fossa of the superotemporal orbit, divided into an orbital lobe and a smaller palpebral lobe by the lateral horn of the levator aponeurosis. Any process that enlarges the gland, inflammatory or neoplastic, pushes the globe inferiorly and medially: the opposite direction from a mass arising in the lacrimal drainage system at the medial canthus. That displacement pattern is often the first clue that a superotemporal mass originates in the lacrimal gland rather than the eyelid or orbital fat.

Lacrimal gland pathology falls into two broad categories: inflammatory disease (dacryoadenitis) and neoplasms. The neoplasms split again into epithelial tumors, chiefly pleomorphic adenoma (benign) and adenoid cystic carcinoma (malignant), and lymphoid or inflammatory lesions that can mimic them on presentation. Getting that distinction right before committing to a surgical plan matters: the correct approach to a benign epithelial tumor is complete excision without biopsy, while the correct approach to inflammatory or lymphoid disease is biopsy first, with medical management likely to follow. Apply either plan to the wrong category and the outcome suffers.

Dacryoadenitis

Dacryoadenitis is inflammation of the main lacrimal gland. It presents with pain, swelling, and erythema over the superolateral orbital rim, often with an S-shaped ptosis of the lateral eyelid as the enlarged gland pushes the lid margin down. Causes split into infectious (viral, particularly mumps, is classic; bacterial cases occur too) and systemic inflammatory disease such as sarcoidosis or IgG4-related disease. Acute infectious dacryoadenitis is usually self-limited or responds to targeted antimicrobial therapy. Chronic or recurrent cases are different: they warrant investigation for an underlying systemic cause and, at times, biopsy to exclude lymphoma or a lymphoproliferative process, a distinct indication for biopsy from a suspected epithelial tumor, where biopsy is avoided.

Lacrimal Gland Biopsy Technique

When biopsy is genuinely indicated (inflammatory or lymphoid disease, not a suspected epithelial tumor, discussed below), the sample is taken from the orbital lobe, not the palpebral lobe. The reason is ductal rather than a matter of surgical convenience: every excretory duct draining the orbital lobe's secretory acini passes through the palpebral lobe on its way to the conjunctival fornix. Biopsying the palpebral lobe risks transecting those ducts and permanently reducing the gland's aqueous tear output, an avoidable, iatrogenic cause of dry eye. Sampling the orbital lobe instead leaves the palpebral lobe's duct network intact.

Pleomorphic Adenoma vs. Adenoid Cystic Carcinoma

These two epithelial tumors are the classic lacrimal gland pair: same location, same lobe of origin, and opposite biology and surgical plan.

Pleomorphic Adenoma (Benign Mixed Tumor)

Pleomorphic adenoma, also called a benign mixed tumor for its combined epithelial and mesenchymal-appearing stromal elements, is the most common benign epithelial tumor of the lacrimal gland. It typically presents as a slow-growing, painless mass that develops over months to years, without bone erosion. The single most important management principle is that incisional biopsy is avoided. Cutting into the tumor risks seeding tumor cells into the surrounding orbital tissue, which promotes local recurrence, and each recurrence carries a rising risk of malignant transformation into carcinoma ex pleomorphic adenoma. The standard of care instead is complete excision with the tumor's pseudocapsule kept intact, performed through a lateral orbitotomy, based on clinical presentation and imaging alone.

Adenoid Cystic Carcinoma

Adenoid cystic carcinoma is the most common malignant epithelial lacrimal gland tumor, and its clinical signature is the opposite of pleomorphic adenoma's. It is classically painful, grows more rapidly, and is prone to perineural invasion, spread along nerve sheaths that both drives the pain and makes clear surgical margins difficult to achieve. Imaging typically shows bone erosion or destruction adjacent to the lacrimal fossa, unlike the well-circumscribed, non-destructive appearance of pleomorphic adenoma. Treatment combines surgical excision, often including orbital exenteration for extensive disease, with adjuvant radiation, but prognosis remains poor: local recurrence and distant metastasis are both common.

Related Topics

Continue exploring Oculoplastics & Orbit: