Bone Pathology III

Question 1

Osteoma

 MC
 May arise from
 Distinct from

Answer 1

Benign tumors composed of mature compact or cancellous bone
craniofacial region
bone surface or within medullary bone
exostosis

Question 2

Osteoma
 Clinical features:
(5)

Answer 2

 Observed in adults
 MC mandibular body and condyle
 Solitary and asymptomatic
 Slow growth
 Large lesions may produce marked facial deformity

Question 3

Osteoma
 Radiographic features:
(2)

Answer 3

 Circumscribed radiopaque mass
 Smaller endosteal osteomas – more discrete

Question 4

Gardner syndrome
(3)

Answer 4

 Characterized by intestinal polyps and abnormalities of bone, teeth, skin,
soft tissue
 Variant of familial adenomatous polyposis
 AD disorder, mutations in APC (tumor suppressor gene)

Question 5

 Variant of familial adenomatous polyposis

Answer 5

 numerous intestinal polyps →colorectal cancer

Question 6

Gardner syndrome
 Clinical features:

 Often
 May cause
 If untreated,

Answer 6

Colorectal polyps develop by 2nd decade
asymptomatic
diarrhea, constipation, abdominal pain
will transform into adenocarcinoma

Question 7

Gardner syndrome
 Clinical features:
lesions (3)

Answer 7

 90% develop skeletal abnormalities: osteomas (multiple)
 Epidermoid cysts
 Pigmented lesions of ocular fundus

Question 8

Gardner syndrome
 Dental abnormalities:
(3)

Answer 8

 Odontomas, supernumerary teeth, impacted teeth

Question 9

Gardner syndrome
 Treatment:
(4)

Answer 9

 Without treatment: 50% develop colorectal cancer by 30 years, nearly 100% by
5th decade
 Prophylactic colectomy recommended
 Osteomas removed for functional issues
 Dental management for impacted teeth, odontomas

Question 10

Osteoblastoma

 Arise from
 MC in

Answer 10

Rare, appx 1% of bone tumors
osteoblasts
vertebral column, long bones, pelvis, facial bones, small bones of
hands and feet

Question 11

Osteoblastoma
 Clinical features:
(4)

Answer 11

 MC in mandible
 85% occur before 30 years
 Dull pain, swelling
 Tooth mobility, root resorption or displacement

Question 12

Osteoblastoma
 Radiographic features:
(2)

Answer 12

 Mixed RL/RO, variable mineralization
 May be well-defined or poorly defined

Question 13

Osteoblastoma
 Treatment:
(2)

Answer 13

 Local excision or curettage
 Recurrence uncommon

Question 14

Cementoblastoma
 Benign neoplasm of —
 Clinical features:
(4)

Answer 14

cementum

 80% mandible (50% 1st molar)
 50% cases arise by 20 years
 Pain and swelling
 Bony expansion uncommon

Question 15

Cementoblastoma
 Radiographic features:
(2)

Answer 15

 Radiopaque mass that is fused to one or more tooth roots
 May be surrounded by thin RL rim

Question 16

Cementoblastoma
 Treatment:

Answer 16

 Surgical extraction of tooth and calcified mass

Question 17

Langerhans cell histiocytosis
(2)

Answer 17

 Proliferation of Langerhans cells (dendritic cells)
 BRAF mutations – 40-60% cases

Question 18

 Proliferation of Langerhans cells (dendritic cells)
(2)

Answer 18

 Antigen presenting cell
 Normally found in epidermis, mucosa, lymph nodes, bone marrow

Question 19

Langerhans cell histiocytosis
 Clinical features:
(5)

Answer 19

 Single organ involvement: bone or skin
 Multi-organ involvement: skin, bone, lymph nodes, lung, liver…
 50% cases <15 years
 Bone lesions – solitary or multiple; Skull, ribs, vertebrae, mandible
 Dull pain, tenderness

Question 20

Langerhans cell histiocytosis
 Clinical features:
 Mucosal involvement:

Answer 20

ulcerative or proliferative gingival mass

Question 21

Langerhans cell histiocytosis
 Radiographic features:
(4)

Answer 21

 Sharply punched-out radiolucency (no corticated rim)
 Occasionally ill-defined
 May resemble aggressive periodontitis
 Extensive alveolar involvement: teeth “floating in air”

Question 22

Langerhans cell histiocytosis
 Histopathologic features:
(4)

Answer 22

 Diffuse infiltration of large, pale-staining mononuclear cells
 Eosinophils
 other mixed inflammatory cells
 Immunohistochemistry (IHC): CD-1a, CD-207 (+)

Question 23

Langerhans cell histiocytosis
 Electron microscope:

Answer 23

 Birbeck granules: rod-shaped cytoplasmic structures

Question 24

Langerhans cell histiocytosis
 Treatment:
(2)

Answer 24

 Accessible bone lesions often treated with curettage – prognosis is good
 Chronic disseminated disease - management complex