ORAL PATHOLOGY II: ODONTOGENIC CYSTS AND TUMOR

AMELOBLASTOMA

Benign tumor with significant recurrence potential

Most aggressive odontogenic tumor.

AMELOBLASTOMA

Most common epithelial odontogenic tumor.

AMELOBLASTOMA



Potential epithelial sources:



Enamel organ



Odontogenic rests (rests of Malassez, rests of Serres)



Reduced enamel epithelium



Epithelial lining of odontogenic cysts (dentigerous cyst)

AMELOBLASTOMA

Clinical features:



Presents as asymptomatic jaw expansion



Can cause large facial deformities



Broad age range from childhood to late adulthood (mean age: 40)



No sex or racial predilection

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Site of predilection: mandibular molar-ramus area



Other sites: maxillary molar area

AMELOBLASTOMA

Radiographic features:



Multilocular or unilocular radiolucency with well defined and sclerotic margins.



In the mandible → appears similar to the central giant cell granuloma

AMELOBLASTOMA:

Solid or multicystic ameloblastoma



More aggressive



High recurrence rate if treated conservatively

AMELOBLASTOMA:

Biologic subtypes:Cystic:

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AKA unicystic ameloblastoma



Less aggressive and less likely to recur

AMELOBLASTOMA:

Biologic subtypes:Cystic:Plexiform unicystic ameloblastoma

Histologic variant of unicystic type

Slow growing and painless swelling

AMELOBLASTOMA:

Biologic subtypes:Cystic:Plexiform unicystic ameloblastoma

AMELOBLASTOMA

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Biologic subtypes:

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Extraosseous peripheral ameloblastomas



Rare



Found in the gingiva and buccal mucosa



Seen in adults age 40-60

AMELOBLASTOMA

Biologic subtypes:Extraosseous peripheral ameloblastoma



Arise from overlying epithelium or rests of Serres



Exhibit a benign non-aggressive course.



Rare recurrence

AMELOBLASTOMA

Biologic subtypes:Sinonasal ameloblastoma



Common in men age 61



Presentation



Nasal obstruction



Epistaxis



Opacification

AMELOBLASTOMA

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Histopathology:



Palisading of columnar cells around epithelial nests



Budding of tumor cells from neoplastic foci

AMELOBLASTOMA

Microscopic subtypes —>Follicular ameloblastoma

composed of islands of tumor cells that mimic the normal dental follicle

AMELOBLASTOMA



Microscopic subtypes—>Plexiform ameloblastoma

neoplastic cells develop into a network of epithelium

AMELOBLASTOMA

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Microscopic subtypes—>Desmoplastic ameloblastoma

stroma is desmoplastic and the tumor islands become squamous appearing (squamoid) or elongated

AMELOBLASTOMA

Microscopic subtypes—>Basaloid ameloblastomas

mimics basal cell carcinoma

AMELOBLASTOMA

Microscopic subtypes—>Granular cell ameloblastoma

neoplastic cells exhibit prominent cytoplasmic granularity

AMELOBLASTOMA



Microscopic subtypes—>Cystic ameloblastoma

composed of a thin epithelial lining containing columnar basal cells with palisaded nuclei showing hyperchromasia and vacuolar change

AMELOBLASTOMA

Treatment:



Solid (multicystic or polycystic) ameloblastoma



Surgical excision



Resection for larger lesions followed by immediate surgical reconstruction



50-90% recurrence rate

Treatment for Unicystic ameloblastoma

Enucleation to resection

Should not be over treated



Peripheral ameloblastoma

Tx for Ameloblastoma Malignant variants

Managed as carcinomas

MALIGNANT AMELOBLASTOMA AND AMELOBLASTIC CARCINOMA

Rare



Seen in the third decade of life



More common in the mandible

MALIGNANT AMELOBLASTOMA AND AMELOBLASTIC CARCINOMA

Metastasizes to the lungs (most common) and regional lymph nodes (second most common) and to the skull, liver, spleen, kidney, and skin.

MALIGNANT AMELOBLASTOMA

Primary and metastatic lesions are microscopically well differentiated with the characteristic histologic features of ameloblastoma

AMELOBLASTIC CARCINOMA

Lesions exhibit less microscopic differentiation showing cytologic atypia and mitotic figures.

CLEAR CELL ODONTOGENIC CARCINOMA

AKA clear cell odontogenic tumor

CLEAR CELL ODONTOGENIC CARCINOMA

Rare neoplasm of the mandible and maxilla

Locally aggressive, poorly circumscribed neoplasm composed of sheets of cells with relatively clear cytoplasm

Histogenic origin: unknown

CLEAR CELL ODONTOGENIC CARCINOMA

Clinical features:



Females over 60



Seen in both mandible and maxilla



Metastasizes to the lung and regional lymph nodes

CLEAR CELL ODONTOGENIC CARCINOMA

Radiographic feature: poorly circumscribed radiolucency

CLEAR CELL ODONTOGENIC CARCINOMA TREATMENT

resection of affected area

ADENOMATOID ODONTOGENIC TUMOR

Formerly called adenoblastoma

ADENOMATOID ODONTOGENIC TUMORS

Benign uncommon to rare odontogenic hamartoma that contains epithelial ductlike spaces and calcified enameloid material

ADENOMATOID ODONTOGENIC TUMOR

AKA two-thirds tumor

ADENOMATOID ODONTOGENIC TUMOR

2/3 of cases are seen in the maxilla, 2/3 of cases are females, 2/3 are found in the anterior jaws and 2/3 are associated with the crown of impacted tooth

ADENOMATOID ODONTOGENIC TUMOR

Clinical features:

Narrow age range from 5 to 30- most ases appear during the second decade

ADENOMATOID ODONTOGENIC TUMOR

—>Clinical features:three variants

Follicular – 73%



Extrafollicular – 24%

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Peripheral – 3%

ADENOMATOID ODONTOGENIC TUMORE: Follicular Variant

Radiographic feature:

Follicular: well circumscribed unilocular radiolucency around the crown of an impacted tooth

ADENOMATOID ODONTOGENIC TUMOR—>Extrafollicular Variant

well-defined unilocular radiolucency above, between, or superimposed over the roots of an unerupted tooth with small opaque foci indicating calcification

ADENOMATOID ODONTOGENIC TUMOR : PERIPHERAL VARIANT

RAD FEATURE:None→ painless, nontender gingival swelling

ADENOMATOID ODONTOGENIC TUMOR

Treatment:



Enucleation



Does not recur following conservative treatment

CALCIFYING EPITHELIAL ODONTOGENIC TUMOR

AKA Pindborg tumor

CALCIFYING EPITHELIAL ODONTOGENIC TUMOR

Benign tumor of odontogenic origin that shares many clinical features with ameloblastoma

CALCIFYING EPITHELIAL ODONTOGENIC TUMOR



Histogenic origin: unknown - dental lamina remnants and the stratum intermedium of the enamel organ have been suggested.

CALCIFYING EPITHELIAL ODONTOGENIC TUMOR

Clinical features:

Wide age range from second to tenth decade – mean age of 40

No gender predilection

CALCIFYING EPITHELIAL ODONTOGENIC TUMOR

More common in the mandible

Site of predilection: molar-ramus region

CALCIFYING EPITHELIAL ODONTOGENIC TUMOR

Locally infiltrative and slow growing



Causes morbidity through direct tumor extension

CALCIFYING EPITHELIAL ODONTOGENIC TUMOR

CALCIFYING EPITHELIAL ODONTOGENIC TUMOR

Radiographic features:



Well-circumscribed unilocular or multilocular (honeycomb) radiolucency associated with an impacted tooth



May have an opaque foci - reflects the calcified amyloid

CALCIFYING EPITHELIAL ODONTOGENIC TUMOR

Histopathology:



Sheets of large polygonal epithelial cells are usually seen with areas of amyloid that have concentric calcified deposits (Liesegang rings) throughout.

CALCIFYING EPITHELIAL ODONTOGENIC TUMOR

Treatment:

Surgery, ranging from enucleation to resection

20% recurrence rate

SQUAMOUS ODONTOGENIC TUMOR



Etiology: neoplastic transformation of rests of Malassez

SQUAMOUS ODONTOGENIC TUMOR



Clinical features:



Sites of predilection: Anterior maxilla and posterior mandible



Seen in the second to seventh decade (mean age: 40years)

SQUAMOUS ODONTOGENIC TUMOR

Clinical features:



No symptoms - tenderness and tooth mobility have been reported

SQUAMOUS ODONTOGENIC TUMOR



Radiographic features: well circumscribed often semilunar radiolucency associated with the roots of teeth

SQUAMOUS ODONTOGENIC TUMOR



Histopathology: Similar to ameloblastoma except for the absence of peripherally palisaded layer of epithelial cells

SQUAMOUS ODONTOGENIC TUMOR

Treatment:

Curettage or excision

Shows infrequent recurrence

AMELOBLASTIC FIBROMA AND AMELOBLASTIC FIBROMA-ODONTOMA

Benign mixed odontogenic tumors composed of neoplastic epithelium and mesenchyme with microscopically identical soft tissue components.

AMELOBLASTIC FIBROMA AND AMELOBLASTIC FIBROMA-ODONTOMA



Clinical features:



Occur in children and young adults → mean age is 12 years (upper age limit is 40)



Affects both genders equally

AMELOBLASTIC FIBROMA AND AMELOBLASTIC FIBROMA-ODONTOMA

Clinical features:



Site of predilection: mandibular molar-ramus region

AMELOBLASTIC FIBROMA AND AMELOBLASTIC FIBROMA-ODONTOMA

Radiographic appearance:

Ameloblastic fibroma: Well-circumscribed unilocular or multilocular radiolucency surrounded by a sclerotic margin and associated with the crown of an impacted tooth

AMELOBLASTIC FIBROMA AND AMELOBLASTIC FIBROMA-ODONTOMA

Ameloblastic fibro-odontoma: Combined lucent-opaque lesion

AMELOBLASTIC FIBROMA AND AMELOBLASTIC FIBROMA-ODONTOMA

Histopathology:

Encapsulated tumor composed of primitive-appearing myxoid connective tissue

AMELOBLASTIC FIBROMA AND AMELOBLASTIC FIBROMA-ODONTOMA

AMELOBLASTIC FIBROMA AND AMELOBLASTIC FIBROMA-ODONTOMA

Treatment:

Enucleation or excision

Rarely recurs

AMELOBLASTIC FIBROSARCOMA



AKA ameloblastic sarcoma

ODONTOMA

Most common odontogenic tumors.

Calcified lesions composed of dental hard tissues

Biologically regarded as hamartomas

ODONTOMA

Clinical features:

Most are discovered in the second decade

More common in the maxilla

No gender predilection

Asymptomatic

ODONTOMA

Clinical features:

Signs indicative of odontoma: retained deciduous tooth, an impacted tooth, and alveolar swelling

ODONTOMA

Two configurations:

Compound odontoma

Complex odontoma

ODONTOMA—>Compound odontoma

Children and young adults

Anterior jaws

Contains miniature teeth

Radiographic appearance: multiple miniature or rudimentary teeth

ODONTOMA—>Complex odontoma

Children and yo ung adults

Posterior jaws

Composed of a conglomerate mass

Radiographic appearance: Amorphous opaque masses

ODONTOMA

.

Histopathology: Normal-appearing enamel, dentin, cementum, and pulp may be seen

ODONTOMA

Treatment:

Enucleation

No recurrence

ODONTOMA—>Odontoameloblastoma Variant

An ameloblastoma in which there is focal differentiation into an odontoma

Treated as an ameloblastoma

CENTRAL ODONTOGENIC FIBROMA

Rare tumor of dense collagen with strands of epithelium

Regarded as the central counterpart to the peripheral odontogenic fibroma.

Associated with giant cell granuloma–like lesions

CENTRAL ODONTOGENIC FIBROMA

Clinical features

Seen in all age groups → children and young adults

2:1 female predilection

CENTRAL ODONTOGENIC FIBROMA

Clinical features

Found in both the mandible and maxilla - 45% in maxilla anterior to first molar

CENTRAL ODONTOGENIC FIBROMA



Clinical features



Smaller ones usually completely asymptomatic.



Larger lesions may be associated with localized bony expansion or teeth loosening.

CENTRAL ODONTOGENIC FIBROMA

Radiographic appearance:

Well-defined radiolucent lesion that is usually multilocular, causing cortical expansion

CENTRAL ODONTOGENIC FIBROMA

Histopathology: 2 patterns

Simple or epithelium-poor type - mass of mature fibrous tissues with few epithelial rests.

CENTRAL ODONTOGENIC FIBROMA



Histopathollogy:Complex type

- mature connective tissue with abundant odontogenic epithelial component in the form of rests, along with calcified deposits believed to be dentin or cementum

CENTRAL ODONTOGENIC FIBROMA

Treatment:

Enucleation orexcision

Recurrence is very uncommon

GRANULAR CELL ODONTOGENIC TUMOR

AKA granular cell odontogenic fibroma

ODONTOGENIC MYXOMA

Benign mesenchymal lesion that mimics microscopically the dental pulp or follicular connective tissue.

Common odontogenic tumor, representing 1% to 17% of all tumor types

ODONTOGENIC MYXOMA

Histogenic origin: dental papilla, dental sac or peridontal ligament

ODONTOGENIC MYXOMA

Clinical features:

An aggressive tumor presenting as a painless swelling

Lesions can cross the midline

ODONTOGENIC MYXOMA

Clinical features:

Seen in individuals from age 10 to 50 – mean age of 30

No gender predilection

ODONTOGENIC MYXOMA

Clinical features:

Either jaw is affected → most common site: posterior mandible

ODONTOGENIC MYXOMA

Radiographic features:

Often multilocular, frequently with a "honeycombed“, “soap bubble” or “tennis racket” pattern.

Cortical expansion or perforation and root displacement or resorption may be seen

ODONTOGENIC MYXOMA

Histopathology:

Composed of bland, relatively acellular myxomatous connective tissue

Benign fibroblasts and myofibroblasts with variable amounts of collagen are found in a mucopolysaccharide matrix.

ODONTOGENIC MYXOMA

Histopathology:

Bony islands, representing residual trabeculae, and capillaries are found scattered throughout the lesion

Unencapsulated

ODONTOGENIC MYXOMA

Histopathology:

When large amounts of collagen are evident – it is called odontogenic fibromyxoma

ODONTOGENIC MYXOMA

Treatment:

Conservative to radical surgical excision – recurrence occurs hen treated very conservatively

Prognosis: good

CEMENTOBLASTOMA

AKA true cementoma

CEMENTOBLASTOMA

Clinical features:

Usually solitary

Slow growing lesion causing expansion of the bony cortex and intermittent pain

Intimately associated with the root of a vital tooth

CEMENTOBLASTOMA

Clinical features:

Occurs predominantly in the second and third decades → before 25 years

No gender predilection

CEMENTOBLASTOMA

Clinical features:

More common in the MANDIBLE than in the maxilla, ANTERIORareas more than the posterior areas

CEMENTOBLASTOMA

Radiographic appearance:

Well-circumscribed radiopaque lesion that replaces the root of the tooth → root outline is obscured by a radiolucent rim.

Usually surrounded by a radiolucent ring.