Pathology · patient case question
What is the diagnosis for Patient B?
Patient case: Two unerupted teeth with pericoronal radiolucencies
Patient: Two patients
Chief Complaint: A: “My eye tooth never came down.” B: routine radiographic review.
Background: A, 16-year-old female: healthy, no symptoms. B, 42-year-old male: healthy, mild expansion of the posterior left mandible noticed by his hygienist.
Findings: A: an unerupted maxillary canine surrounded by a well-defined radiolucency that envelops the crown AND continues apically along the root, clearly PAST the cementoenamel junction. Faint flecks of radiopacity are visible within the lucency. B: an unerupted mandibular third molar within a lucency containing scattered calcifications of markedly varying size and density, some appearing ring-like.
Show answer and explanation
Correct answer: B. Calcifying epithelial odontogenic tumour (Pindborg tumour)
- A. Odontogenic myxoma is purely RADIOLUCENT with fine straight septa. It contains no calcified material.
- B. CORRECT. The CALCIFYING EPITHELIAL ODONTOGENIC TUMOUR, or PINDBORG TUMOUR, favours the POSTERIOR MANDIBLE in adults in the fourth to fifth decades and is associated with an unerupted tooth in roughly half of cases. The radiographic hallmark is scattered calcifications of varying size and density within the lucency — the DRIVEN SNOW appearance. Histologically it shows sheets of polyhedral epithelial cells with striking nuclear pleomorphism that does NOT indicate malignancy, prominent intercellular bridges, and amyloid-like material that calcifies in concentric LIESEGANG RINGS and stains with Congo red with apple-green birefringence under polarised light. It is locally invasive, so treatment is local resection with margins rather than simple enucleation, and recurrence runs around 15%.
- C. Ameloblastoma classically produces a multilocular soap-bubble or honeycomb radiolucency of the posterior mandible with marked expansion and knife-edge root resorption — but it does NOT contain scattered internal calcifications.
- D. AOT is a lesion of the ANTERIOR MAXILLA in a young female, encapsulated and cured by enucleation. The age, the site and the behaviour of this lesion all differ.
Note: Two tumours, both associated with an unerupted tooth, both containing calcifications — and separated by everything else. AOT: young female, anterior maxilla, encapsulated, enucleate, no recurrence. CEOT: middle-aged adult, posterior mandible, locally invasive, resect, 15% recurrence.