Glandular Odontogenic Cyst

Glandular odontogenic cyst is a rare, locally aggressive developmental odontogenic cyst lined by epithelium with glandular and mucous features. It makes up well under 1% of odontogenic cysts.

It affects adults in the fifth and sixth decades, with a mandibular predominance of about 70%, particularly the anterior region crossing the midline. Its importance is a high recurrence rate and a resemblance to low grade mucoepidermoid carcinoma on histology.

Pathophysiology. The cyst is thought to arise from odontogenic epithelium with a capacity for glandular differentiation. The lining contains mucous cells, ciliated cells and intraepithelial microcysts.

It tends to grow expansively, perforate cortex and develop satellite loculi, which explains the recurrence.

Slowly enlarging, painless swelling of the jaw in most, with cortical expansion, perforation or displacement of teeth. Some have pain, paraesthesia or discharge. Large lesions can weaken the mandible and cause pathological fracture.

Rapid growth, lip numbness or an ulcerated mass suggests malignancy and needs urgent biopsy.

• Panoramic radiograph: a well defined unilocular or multilocular radiolucency with scalloped or corticated borders, often anterior mandible, with root divergence or resorption and cortical perforation.
• Cone beam CT or MRI for extent, loculation and soft tissue involvement.
• Incisional biopsy: cuboidal or columnar epithelium with cilia, mucous cells, clear cells, microcysts and papillary tufts, with mucin stains positive. Give the pathologist the clinical and radiographic findings.
• Molecular testing for MAML2 rearrangement when the histology resembles mucoepidermoid carcinoma. The absence of the rearrangement supports glandular odontogenic cyst.
• Chest radiograph or staging imaging only if malignancy is found.

Differential diagnosis.

• Low grade central mucoepidermoid carcinoma
• Odontogenic keratocyst
• Lateral periodontal cyst and botryoid cyst
• Unicystic ameloblastoma
• Radicular or dentigerous cyst
• Central giant cell granuloma
• Aneurysmal bone cyst

• Enucleation with peripheral ostectomy and application of a modified Carnoy solution (without chloroform) or cryotherapy to the bone cavity, for small and unilocular lesions.
• Marginal or segmental resection with 0.5 to 1 cm margins for large, multilocular or recurrent lesions, with reconstruction (bone graft or plate) as needed.
• Reported recurrence is about 20 to 50% after enucleation, and much lower after resection, though figures are from small series with lower certainty.
• Antibiotics only for infection with spread: amoxicillin 500 mg orally three times daily for 5 days (reduce to 500 mg every 12 hours at eGFR 10 to 30), or clindamycin 300 mg four times daily in penicillin allergy.
• Analgesia: paracetamol 1 g every 6 hours (maximum 4 g daily) with ibuprofen 400 mg every 8 hours with food.

Monitoring. Radiographs every 6 months for 2 years, then annually for at least 10 years, because late recurrence occurs.

Referral and escalation. Refer to oral and maxillofacial surgery for biopsy and planning. Urgent referral for rapid growth, destructive features, lip numbness, or histology suggesting carcinoma.