Pathology · patient case with 3 questions
Bilateral jaw expansion in a young child
Patient: Male, 6 years old
Chief complaint: "His cheeks have been getting fuller on both sides for about a year. It does not hurt him."
History: Otherwise healthy. No trauma, no fever, no weight loss. The father was told as a child that he had "chubby cheeks" that settled on their own during his teens.
Findings: Painless, firm, bilaterally symmetric expansion of the posterior mandible. Lymph nodes not enlarged. Panoramic and PA radiographs show bilateral, symmetric, expansile multilocular radiolucencies of the mandible with displaced and unerupted teeth.
Question 1
Which cell is primarily responsible for producing the radiographic pattern seen in this patient?
Show answer and explanation
Correct answer: B. Osteoclasts
- A. Osteoblasts DEPOSIT bone. They are recruited later, during the reparative phase after puberty when the lesions fill in with bone — but they do not create the radiolucency.
- B. CORRECT. Cherubism is driven by an SH3BP2 mutation that produces hyperactive OSTEOCLAST signalling through the RANK/RANKL pathway. The lesions consist of vascular fibrous tissue packed with multinucleated OSTEOCLAST-type giant cells, and it is their resorption of bone that carves out the multilocular radiolucent spaces seen on the film.
- C. Odontoclasts resorb dental hard tissue (root resorption, shedding of primary teeth). Teeth in cherubism are displaced and unerupted, but the radiolucency is BONE loss, not tooth loss.
- D. Odontoblasts form DENTIN within the tooth. They have no role in the resorption of jaw bone and could not produce a radiolucent bone pattern.
Note: Histologically the giant-cell lesion of cherubism is indistinguishable from central giant cell granuloma and from the brown tumour of hyperparathyroidism. Bilateral symmetry plus the age of onset is what makes the diagnosis, not the biopsy.
Question 2
How would you describe the observed radiographic pattern?
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Correct answer: D. Multilocular
- A. A cotton-wool appearance — patchy radiopacities on a dense background — belongs to the late osteoblastic phase of Paget disease of bone, a condition of older adults.
- B. A ground-glass or granular pattern with poorly defined margins indicates fibrous dysplasia, which is characteristically UNILATERAL and does not produce distinct loculations.
- C. Punched-out lesions are discrete, rounded, non-corticated lucencies scattered through the skeleton — the hallmark of multiple myeloma, and again a disease of adults.
- D. CORRECT. MULTILOCULAR — expansile radiolucencies subdivided by bony septa, often described as soap-bubble. In cherubism this appears BILATERALLY and SYMMETRICALLY, most often in the posterior mandible and mandibular angles, and may extend to the maxillary tuberosities.
Question 3
What is the most appropriate management approach at this stage?
Show answer and explanation
Correct answer: C. Clinical and radiographic observation, with intervention reserved for functional or severe cosmetic problems
- A. Radiation is contraindicated. Irradiating the jaws of a child with a BENIGN self-limiting condition risks growth arrest and radiation-induced malignancy.
- B. Aggressive resection is not indicated for a condition that regresses on its own, and operating during the active phase is associated with rapid recurrence and needless loss of bone in a growing child.
- C. CORRECT. Cherubism is SELF-LIMITING. Lesions enlarge until puberty, then stabilise and progressively regress with bony infill through the late teens and twenties. Observation is therefore the default. Surgery — usually contouring rather than resection — is deferred until after growth unless the lesions threaten vision, breathing, speech, eruption or produce severe deformity.
- D. Bisphosphonates and other antiresorptives have been reported anecdotally, but there is no established indication for routine use, and antiresorptives in a growing child carry their own risks.