Odontogenic Tumors PDF

Odontogenic Tumors Odontogenic Epithelium and Ectomesenchyme Outer enamel epithelium Stellate reticulum Stratum inter...

Odontogenic Tumors Odontogenic Epithelium and Ectomesenchyme Outer enamel epithelium Stellate reticulum Stratum intermedium Inner enamel epithelium Dental papilla Dental follicle  Tissue of Origin Epithelial only Ameloblastoma CEOT AOT Primary intraosseous carcinoma of the jaws Ectomesenchymal only Cementoblastoma Odontogenic myxoma Epithelial and ectomesenchymal Ameloblastic fibroma Odontoma  Ameloblastoma Benign tumor with persistent, aggressive growth pattern Epithelial tumor: derived from enamel organ  Ameloblastoma 2022 WHO Classification: Conventional ameloblastoma Unicystic ameloblastoma Extraosseous/peripheral ameloblastoma Conventional Ameloblastoma: Clinical Features Comprises approximately 80% of ameloblastomas Occurs most often in 4th and 5th decades, with wide age range 85% in mandible, mostly posterior body and ramus Slow, painless expansion in the buccal/lingual dimension Ameloblastoma Ameloblastoma Ameloblastoma: Radiographic Features Location: Solitary, arising in alveolar process (usually), can be pericoronal Observations: Well-defined, corticated, irregular radiolucency, 1 to 10 cm or larger Unilocular, especially when small, or multilocular Multilocular pattern with coarse trabeculae Ameloblastoma: Radiographic Features General effects: Irregular outline, expands and eventually resorbs cortex Root resorption and tooth displacement common Displacement of IAC  Ameloblastoma It starts small …  Ameloblastoma But often gets bigger …  Ameloblastoma … and bigger … Dentalorg.com  Ameloblastoma … and BIGGER! Webpathology.com  Ameloblastoma Resorption of roots Dentalorg.com Ameloblastoma Displacement of teeth Expansion of the cortex Dentalorg.com Ameloblastoma: Differential Diagnosis Odontogenic cysts: OKC Lateral periodontal cyst Ameloblastoma: Histologic Features At least six histologic patterns Follicular pattern most common Islands of odontogenic epithelium with tall columnar peripheral cells resembling ameloblasts Delicate spindle cells resembling stellate reticulum in center of islands Ameloblastoma: Histologic Features Ameloblastoma: Treatment and Prognosis Wide excision; resection for large lesions with wide surgical margins Tumor is locally infiltrative in trabecular bone Recurrence is common Unicystic Ameloblastoma Ameloblastoma arising in epithelium of odontogenic cyst, or de novo as a neoplasm Accounts for 15% of all ameloblastomas Grossly a cystic lesion Unicystic Ameloblastoma: Clinical Features Most occur in 2nd or 3rd decade -- younger than ameloblastoma Over 90% in mandible, mostly posterior Most are asymptomatic; large lesions can expand the jaw Unicystic Ameloblastoma: Radiographic Features Location: Often pericoronal Observations: Well-defined, corticated round or oval radiolucency Unilocular, representing solitary cystic nature of lesion General effects: displacement of teeth or other structures, root resorption, cortical resorption Unicystic Ameloblastoma: Radiographic Features Unicystic Ameloblastoma: Differential Diagnosis Dentigerous cyst (when pericoronal), Other odontogenic cysts: OKC Orthokeratinized odontogenic cyst Unicystic Ameloblastoma: Histologic Features Cyst-like cavity lined by odontogenic epithelium Basal columnar cells resembling ameloblasts Overlying delicate spindle cells resembling stellate reticulum Unicystic Ameloblastoma: Treatment and Prognosis Enucleation may be successful Wider excision may be needed Surgery more conservative than for ameloblastoma Recurrence less common than for ameloblastoma Extraosseous/Peripheral Ameloblastoma Soft tissue variant of ameloblastoma 1% of all ameloblastomas Arises from odontogenic epithelial rests in gingiva May also arise from basal cells of surface epithelium Extraosseous/Peripheral Ameloblastoma: Clinical Features Usually occurs in middle age -- average age 52 Painless sessile or pedunculated mass on gingiva Most common in posterior mandible Extraosseous/Peripheral Ameloblastoma Extraosseous/Peripheral Ameloblastoma: Differential Diagnosis Peripheral soft tissue lesions: Peripheral ossifying fibroma Peripheral giant cell granuloma Peripheral fibroma Gingival cyst of the adult Extraosseous/Peripheral Ameloblastoma: Histologic Features Similar to intrabony ameloblastoma Connection to surface epithelium in 50% of cases Extraosseous/Peripheral Ameloblastoma: Treatment and Prognosis Conservative excision, recurrence rate 15% - 20% Recurrence is rare following second surgery Much better prognosis than intrabony ameloblastoma Calcifying Epithelial Odontogenic Tumor (CEOT) (Pindborg Tumor) Benign odontogenic tumor resembling ameloblastoma in clinical and radiographic appearance Derived from enamel organ Dr. Jens Pindborg CEOT: Clinical Features Similar to ameloblastoma: Most common in adults in 4th and 5th decades Most cases in mandible (75%), usually molar-ramus area Slow, painless enlargement of jaw Prominent buccal-lingual expansion CEOT CEOT: Radiographic Features Location: Solitary lesion in alveolar process, 50% pericoronal Observations: Well-defined unilocular or multilocular lesion, often corticated May be radiolucent only or radiolucent with radiopaque foci Radiopacities may cluster around crown in pericoronal lesions General effects: Cortical expansion and resorption Root resorption and displacement common  CEOT Brit J OMS CEOT Quizlet.com  CEOT “Driven snow” pattern  CEOT: Differential Diagnosis Radiolucent: resembles ameloblastoma or other odontogenic cysts and tumors May consider dentigerous cyst (if pericoronal) Radiolucent/radiopaque: COC (Gorlin cyst) and other mixed odontogenic lesions Pindborg and Gorlin CEOT: Histologic Features Sheets of large, polygonal eosinophilic cells Pleomorphic, with large nuclei, but benign! Concentric calcifications (Liesegang rings) Amyloid-like material in many lesions - stains with Congo red and thioflavin T CEOT CEOT: Treatment and Prognosis Conservative excision; resection for large lesions Much better prognosis than ameloblastoma Adenomatoid Odontogenic Tumor (AOT) Benign odontogenic tumor of epithelial origin Origin in enamel organ Epithelial cells form patterns resembling glandular tumors  AOT: Clinical Features Most occur in 1st and 2nd decades; very rare after age 30 Most patients are females (2:1 female/male ratio) Majority occur in maxilla, usually anterior  AOT: Clinical Features Most lesions are small (< 3.0 cm) Large lesions can cause buccal-lingual expansion Usually asymptomatic  AOT healthsciences.ac.in AOT: Radiographic Features Location: solitary, 75% are pericoronal Observations: Well-defined, often corticated unilocular lesion, small or large Usually completely radiolucent, but may have small radiopaque foci Pericoronal lesions often engulf most of tooth, extending apically past cemento-enamel junction (differs from dentigerous cyst) General effects: Can displace teeth and other structures, resorb roots AOT AOT AOT: Differential Diagnosis Radiolucent: dentigerous cyst (if pericoronal), OKC, unicystic ameloblastoma Radiolucent with radiopaque foci: CEOT (Pindborg), COC (Gorlin) AOT: Histologic Features Columnar or cuboidal cells forming duct-like structures lined by columnar cells Spindle-shaped epithelial cells in whorls or sheets Amorphous material similar to amyloid may be present Bone and other calcifications may form AOT AOT: Treatment and Prognosis Enucleation sufficient due to thick capsule Prognosis excellent; recurrence very rare  Primary Intraosseous Carcinoma of the Jaws Sometimes termed odontogenic carcinoma Carcinoma in jaws with no connection to oral or skin epithelium Can arise de novo or in a pre-existing cyst or tumor Residual radicular cysts and dentigerous cysts are most likely sources Mucoepidermoid carcinomas may arise from mucus cells in dentigerous cysts  Primary Intraosseous Carcinoma of the Jaws: Clinical Features Mostly in older adults (mean age in 6th decade), most in men Usually asymptomatic but may cause pain and swelling Primary Intraosseous Carcinoma of the Jaws: Radiographic and Histologic Features Radiographic Features: Radiolucency with irregular, ragged periphery Histologic Features: Squamous cell carcinoma arising in epithelial lining May see mucoepidermoid carcinoma arising in dentigerous cysts  Primary Intraosseous Carcinoma of the Jaws Spadari F et al. Ann Stomatol (Roma). 2013 Oct 24;4(Suppl 2):38 Primary Intraosseous Carcinoma of the Jaws: Treatment and Prognosis Resection, with or without chemotherapy and/or radiation Prognosis uncertain, but overall not good 5 year survival rate approximately 50% Cementoblastoma: Clinical Features Benign odontogenic tumor of cementoblasts Large majority in late teens, early 20s 75% in mandible; 90% in molar/premolar Most common location: mandibular first molar Pain and swelling in many cases Cementoblastoma: Clinical Features www.contempclindent.org Cementoblastoma: Radiographic Features Location: Solitary lesion, attached to tooth root; most commonly affects 1st molar Observations: Calcified mass attached to tooth root, obliterates outline of root Radiopacity often lobular or radiating Peripheral radiolucency Usually at least 1 cm General effects: Displacement of teeth and other structures, root resorption Cementoblastoma Cementoblastoma dentistaspucmm.wordpress.com Cementoblastoma Cementoblastoma: Histologic Features Sheets and trabeculae of cementum fused to root with irregular lacunae Multinucleated cells and blast cells line the trabeculae Cellular fibrovascular connective tissue between trabeculae Cementoblastoma Cementoblastoma: Treatment and Prognosis Extraction of tooth and attached tumor Prognosis excellent if lesion completely removed  Odontogenic Myxoma Benign odontogenic tumor of ectomesenchymal origin Resembles developing tooth microscopically Odontogenic Myxoma: Clinical Features Most occur in young adults; mean age 25 - 30 with wide age range Slightly more common in mandible Occurs equally in anterior and posterior Odontogenic Myxoma: Clinical Features Slow, painless expansion Can sometimes grow rapidly due to accumulated ground substance Can cause displacement of teeth and root resorption Odontogenic Myxoma  Odontogenic Myxoma: Radiographic Features Location: Solitary lesion in alveolar process Observations: Well-defined unilocular or multilocular irregular radiolucency May have delicate trabeculae and “honeycomb” pattern: very common Can be very large General effects: Resorption and expansion of cortex can be significant Odontogenic Myxoma Odontogenic Myxoma  Odontogenic Myxoma: Differential Diagnosis Odontogenic cysts: OKC Odontogenic tumors: Ameloblastoma, CEOT  Odontogenic Myxoma: Histologic Features Delicate, myxomatous connective tissue with ground substance matrix Mostly hyaluronic acid and chondroitin sulfate Scanty numbers of spindle-shaped fibroblasts No capsule Resembles dental papilla  Odontogenic Myxoma Dental papilla Odontogenic myxoma Odontogenic Myxoma: Treatment and Prognosis Curettage for small lesions; excision for larger lesions Slimy, gelatinous nature of lesion makes complete removal difficult Ameloblastic Fibroma: Benign tumor of epithelial and ectomesenchymal odontogenic tissue Ameloblastic Fibroma: Clinical Features Most occur in 1st and 2nd decades Equal in males and females Mostly in posterior mandible (molar-ramus area) or maxilla Usually asymptomatic Larger lesions can expand the jaw Ameloblastic Fibroma: Clinical Features Ameloblastic Fibroma: Radiographic Features Location: Solitary lesion, 75% are pericoronal Observations: Well-defined often corticated radiolucency, variable size Unilocular or multilocular General effects: Large lesions can extend into ramus and body Tooth displacement and root resorption Displacement of other structures  Ameloblastic Fibroma Carroll C et al. Case reports in dentistry, 2019  Ameloblastic Fibroma: Differential Diagnosis Dentigerous cyst (if pericoronal) OKC, AOT also occur in young patients Ameloblastoma  Ameloblastic Fibroma: Histologic Features Cords and islands of cuboidal odontogenic epithelium resembling ameloblastoma Fibrous stroma of delicate tissue with mesenchymal cells, resembling dental papilla Ameloblastic Fibroma: Treatment and Prognosis Conservative excision usually adequate Wider excision for recurrences Rare transformation into ameloblastic fibrosarcoma  Odontoma Benign odontogenic lesion of ectodermal and ectomesenchymal origin Probably a hamartoma instead of neoplasm Produces dental tissues (enamel, dentin, pulp): “tooth tumor” Most common odontogenic “tumor” Two forms: Compound Complex Odontoma: Clinical Features All Odontomas Occur in 1st and 2nd decades Often pericoronal Enlargement of alveolar process often seen Odontoma: Clinical Features Compound Odontoma Mostly in anterior maxilla Produces enamel, dentin, pulp in the form of little teeth Complex Odontoma Mostly in posterior mandible or maxilla Produces dental tissues in jumbled, amorphous mass (not discrete tooth forms) Odontoma: Radiographic Features Compound Odontoma Multiple small tooth forms with enamel, dentin, pulp and cementum in proper orientation Radiolucent periphery Complex Odontoma Amorphous radiopaque mass of dental hard and soft tissues; no tooth forms Radiolucent periphery Odontoma Odontoma: Compound Odontoma: Compound Odontoma: Complex Odontoma: Differential Diagnosis Well-developed odontoma is usually pathognomonic Odontoma: Histologic Features Normal enamel matrix, dentin, cementum, and pulp in form of teeth or in a shapeless mass Delicate fibrous connective tissue Odontoma: Treatment and Prognosis Excision; lesion usually shells out due to peripheral fibrous connective tissue capsule Prognosis is excellent; recurrences quite rare