Botryoid odontogenic cyst

The botryoid odontogenic cyst (BOC) is a rare, benign, developmental odontogenic cyst classified as the polycystic (multicystic) variant of the lateral periodontal cyst (LPC).[1][2] It arises from rests of the dental lamina within the alveolar bone and is defined histologically by the presence of multiple cystic compartments, which produce a characteristic grape-like (botryoid) gross morphology.[2][3] The mandibular premolar–canine region is the most common site.[1][4] Radiographically, BOC presents as a well-defined radiolucency that may be unilocular or multilocular; notably, the multilocular histological architecture does not always translate into a multilocular radiographic appearance.[1] Compared with LPC, BOC demonstrates a substantially higher recurrence rate (approximately 22%), warranting more aggressive surgical management and prolonged surveillance.[1]

The 5th edition WHO Classification of Head and Neck Tumours (2022) groups BOC under "Cysts of the Jaws," eliminating the prior distinction between odontogenic and non-odontogenic origin.[5] BOC is recognized as a polycystic variant of the lateral periodontal cyst.[1][6]

• Current accepted name: Botryoid odontogenic cyst (BOC)
• Parent entity: Lateral periodontal cyst
• Synonym: Botryoid variant of lateral periodontal cyst
• Obsolete/historical usage: The term was first applied by Weathers and Waldron in 1973 to describe a multiloculated variant of LPC. Some authors have advocated restricting "botryoid odontogenic cyst" to a gross and histopathologic descriptor rather than a standalone diagnosis.[2][3]

• Frequency: BOC is rare. In a multicentre study of over 25,000 jaw cysts, LPC and BOC combined accounted for only 1.3% of all cases. A systematic review identified 96 BOC cases across 146 publications.[1][7]
• Age: Peak prevalence in the sixth and seventh decades of life, with a mean age of approximately 54 years—older than patients with LPC (mean ~47 years). A case series of 33 BOCs reported a mean age of 57 years.[1][8]
• Sex: No significant sex predilection; distribution is approximately equal between males and females. Some reports suggest a slight female predominance.[1][4][9]
• Anatomic distribution: The mandible is the predominant site (approximately 85% of cases), with the premolar–canine region most frequently affected, followed by the anterior mandible. Maxillary lesions occur less commonly, typically in the anterior region.[4][8][9][10]

BOC is usually asymptomatic and discovered incidentally on routine radiographic examination.[10]

Presentation

• Most lesions are clinically silent; the overlying mucosa appears normal.[10]
• When symptomatic, patients may report painless swelling of the alveolar ridge or buccal vestibule.[4][9]
• Adjacent teeth characteristically test vital on pulp testing, which is a key clinical clue distinguishing BOC from inflammatory periapical pathology.[10][11]

Examination findings

• Soft-tissue swelling, when present, is typically firm and non-tender.
• Probing depths around adjacent teeth are usually within normal limits.[10]
• Larger lesions may produce visible buccal or lingual expansion.[3]

Tempo and complications

• Growth is slow and progressive.[11]
• Cortical perforation can occur, particularly with larger lesions.[2]
• Rare reports describe lesions becoming locally destructive.[3]
• Ameloblastoma and squamous cell carcinoma have been reported in rare association with LPC-family cysts.[11]

Location and distribution

BOC occurs most frequently in the mandibular premolar–canine region, followed by the anterior mandible and the anterior maxilla.[4][8][9] Lesions are characteristically located lateral to the roots of erupted, vital teeth, between the alveolar crest and the root apex—mirroring the position of its parent entity, the LPC.[11] Occasional cases arise in the posterior mandible, including the premolar–molar region.[4]

Periphery and shape

• The periphery is typically well-defined and corticated, presenting as a sharply demarcated radiolucency.[10][11]
• Shape varies from round or oval to lobulated or polycyclic, depending on the number and arrangement of cystic compartments.[3][9]
• Smaller lesions may appear round or teardrop-shaped, indistinguishable from a unilocular LPC.[11]

Internal architecture

• BOC may present as either unilocular or multilocular on conventional radiographs.[1][3]
• In the systematic review by Chrcanovic and Gomez, BOC demonstrated a multilocular radiographic appearance more frequently than LPC, but unilocular presentation remains common—approximately 60% of BOCs in one literature review appeared unilocular.[1][9]
• In the Greer and Johnson series of 10 BOCs, only 2 were radiographically multilocular despite all being histologically polycystic.[3]
• This discrepancy is a critical teaching point: multilocular histology does not necessarily produce a multilocular radiographic appearance.[1][3]
• When multilocular, the internal septa create a grape-like or clustered pattern of radiolucent compartments.
• The internal density is uniformly radiolucent without calcified contents.

Effects on teeth and adjacent structures

• Adjacent teeth remain vital, which is a hallmark distinguishing BOC from inflammatory cysts.[10]
• Root divergence may occur with larger lesions.[11]
• Root resorption is not a prominent feature but has been reported occasionally.
• Tooth displacement is uncommon in smaller lesions but may be seen as lesion size increases.

Growth pattern, cortical involvement, and extent

• Growth is slow and expansile.[11]
• Cortical expansion is generally modest; marked buccal or lingual expansion is uncommon in smaller lesions but can occur with larger BOCs.[2][3]
• Cortical perforation is rare but has been documented, particularly in larger or recurrent lesions.[2]
• Multilocular BOCs are significantly larger than unilocular ones (mean 3.6 cm vs. 1.8 cm).[1]

Prognostic radiographic features

• Multilocular radiographic appearance is the only variable shown to significantly affect recurrence rate. All recurrent BOCs in the systematic review were multilocular on imaging.[1]
• Multilocular BOCs also tend to be larger, compounding the recurrence risk.[1]

The differential for BOC depends on whether the lesion appears unilocular or multilocular. A unilocular, well-corticated radiolucency lateral to vital tooth roots in the premolar–canine region generates a narrow differential centered on developmental odontogenic cysts. Multilocular presentations broaden the differential to include other polycystic or neoplastic entities.

The highest-risk diagnostic pitfall is misidentifying a BOC as a simple LPC, because the two share overlapping radiographic and clinical features yet differ markedly in recurrence behavior. Biopsy with complete histopathological examination—specifically evaluating for multiple cystic compartments—is essential for all lateral radiolucencies associated with vital teeth, as the distinction directly affects surgical planning and follow-up intensity.[10][12]

Defining microscopic features

The hallmark of BOC is the presence of multiple cystic compartments (polycystic architecture), which distinguishes it from the unicystic LPC.[1][2] Each compartment is lined by thin, non-keratinized stratified squamous epithelium, typically 1–5 cell layers thick.[2]

Characteristic epithelial features

• Focal plaque-like thickenings: Discrete areas of epithelial thickening that interrupt the otherwise thin lining.[1][2]
• Glycogen-rich clear cells: Present within the epithelial plaques; these cells stain positively for glycogen (PAS-positive, diastase-sensitive).[2]
• The fibrous connective tissue wall is typically thin with minimal or no inflammation.[1]
• Small islands of odontogenic epithelium may be present in the cyst wall.[15]

Radiologic–pathologic correlation

A critical point is that the polycystic histological architecture may produce either a unilocular or multilocular radiographic appearance.[1][3] When multiple cystic spaces are small or closely apposed, they may project as a single radiolucent cavity on conventional radiographs. This discordance underscores the necessity of histological examination for definitive classification.

Differential histopathological considerations

• LPC shares the same epithelial lining pattern but is unicystic.[1][6]
• Glandular odontogenic cyst may show plaque-like thickenings and clear cells but additionally contains mucous cells, hobnail cells, ciliated cells, microcysts, and glandular spaces—features absent in BOC.[6][13]

Treatment

• Enucleation is the most commonly employed treatment (approximately 54% of reported cases), followed by curettage (approximately 45%).[1]
• Given the relatively high recurrence rate, adjunctive therapy after enucleation—such as peripheral ostectomy, cryotherapy, or application of Carnoy's solution—has been recommended, although evidence specific to BOC remains limited and is extrapolated from experience with other recurrence-prone odontogenic cysts.[1]
• Decompression/marsupialization has been used as an initial approach for larger lesions approximating vital structures (e.g., the inferior alveolar nerve), followed by delayed enucleation once the lesion has decreased in size.[4]

Recurrence

• The recurrence rate for BOC is approximately 22%, substantially higher than LPC (2.4%) and comparable to odontogenic keratocyst and glandular odontogenic cyst.[1]
• An earlier literature review of 67 cases reported a recurrence rate of 32% among cases with follow-up data.[9]
• Recurrence may be delayed: the mean interval between treatment and recurrence is approximately 6.5 years, with recurrences documented as late as 13 years after initial surgery.[1][3]
• All recurrent BOCs in the systematic review demonstrated a multilocular radiographic appearance, and multilocular lesions were significantly larger than unilocular ones.[1]

Surveillance

• Long-term radiographic follow-up is essential, given the potential for late recurrence.[3]
• Follow-up should extend for a minimum of several years; some authors advocate surveillance beyond 10 years, particularly for multilocular lesions.[1][3]
• Periodic clinical and radiographic evaluation allows early detection of recurrence when re-treatment is less morbid.

Prognosis

• BOC is a benign lesion with no documented potential for malignant transformation specific to the entity itself, although rare associations of ameloblastoma and squamous cell carcinoma with LPC-family cysts have been reported.[11]
• Prognosis after adequate surgical treatment is favorable, but the clinically significant recurrence rate mandates vigilant long-term follow-up.[1][3]