Question

A 58 year-old male received a referral to his physician from his dentist. This patient exhibited progressive swelling (over the period of the last 4 years) in the right and left maxilla which was causing difficulty with chewing during eating. Upon examination, the physician found swelling in the frontal, malar, and maxillary regions of the skull.

1. What is your initial presumptive diagnosis? What is your alternative diagnosis?
2. Describe the disease process, any additional associated symptoms, and expected prognosis?
3. What labs should be ordered to determine the cause of the bony growths and what labs values would you expect to see if your initial presumptive diagnosis is correct?

Answer 1

Ans) Initial presumptive diagnosis:

- On examination, extra-orally bilateral diffuse swellings were seen in the malar and zygomatic region bilaterally, obliterating the nasolabial sulcus and in the right frontal region, which were bony hard in consistency on palpation. The swellings were immobile and attached to the underlying bone. Intra-orally, diffuse swelling of the maxillary alveolus was seen bilaterally, extending from 18 to 28 region with obliteration of the buccal sulcus. Bicortical expansion was seen in the maxillary premolar-molar region, which were non-tender and hard in consistency, attached to the underlying bone. The occlusion was deranged and on occluding, the teeth were not in contact.

Alternative diagnosis:

Facial profile of the patient, right side showing swelling in the frontal, malar and maxillary region, relative maxillary prognathism with apparent leontiasis ossea.

- Intra-oral picture of the maxillary arch showing bilateral enlargement and bicortical expansion

Disaease process:

- Since, the swellings were multiple, bilateral, gradually increasing in size, asymptomatic, and bony hard in consistency a provisional diagnosis of disorder of bone was made; radiologic, biochemical and histopathologic investigations were performed.

Periapical, occlusal, and panoramic radiographs reveal diffuse radiopacities and hypercementosis of roots of the maxillary teeth. Postero-anterior and Lateral view of the skull reveal generalized flecks of irregularly shaped radiopacities involving the entire skull, giving a cotton wool appearance.

Labs:

- Computed tomography scan reveals osteosclerosis of right maxillary, ethmoid, frontal, and sphenoid sinuses with widening of diploic space with sclerotic and lytic areas involving inner and outer tables of bony calvarium. There is an expansion, with sclerosis of all walls of right maxillary, right ethmoid, and floor of left maxillary sinus.

- Coronal view of computed tomography scan showing widened diploic space with sclerotic and lytic areas involving inner and outer tables of bony calvarium giving a cotton wool appearance (yellow arrow) with obliteration of the maxillary antrum on right.

- Biochemical tests revealed normal serum calcium: 9.2 mg/dL and serum phosphorus: 4 mg/dl, but markedly raised serum alkaline phosphatase (SAP): 1251 IU and urinary hydroxy-proline: Creatine ratio: 243.6 mmol.

- An incisional biopsy of the swelling was carried out in the left maxillary alveolus. Histopathologic examination revealed a cellular proliferating inter-trabecular fibroblastic marrow with many clusters of osteoclasts separating spicules of bone, which appear lamellar in some of the bits with numerous cement lines forming a mosaic pattern. Trabecula of bone with basophilic reversal lines in connective tissue stroma are seen.

- H and E section in low power magnification (×10) showing jig-saw puzzle or mosaic pattern of bony trabeculae with osteocytes (blue arrows) and basophilic reversal lines (yellow arrows)

- Correlating the clinical, radiologic, biochemical, and histopathologic findings a final diagnosis of PDB was established. Patient was referred to the Rheumatologist for treatment.