Which odontogenic tumor is the LEAST clinically aggressive?

Correct answer: D. Adenomatoid odontogenic tumor (AOT)

• A. Conventional ameloblastoma is a benign but LOCALLY AGGRESSIVE, infiltrative tumor with a high recurrence rate after simple enucleation. It requires resection with margins — far more aggressive than AOT.
• B. Clear cell odontogenic carcinoma is a frank MALIGNANCY, with local destruction, a marked tendency to recur, and the capacity to metastasise to lung and regional nodes.
• C. Ameloblastic fibrosarcoma is the malignant counterpart of ameloblastic fibroma, in which the MESENCHYMAL component becomes sarcomatous. It is rapidly growing and destructive.
• D. CORRECT. The ADENOMATOID ODONTOGENIC TUMOR is the classic 'two-thirds tumor': two-thirds in the maxilla, two-thirds in females, two-thirds in the second decade, two-thirds associated with an impacted tooth (most often a canine). It is a well-encapsulated, slowly growing hamartomatous lesion that shells out easily with simple ENUCLEATION and essentially never recurs. It is the benchmark for a non-aggressive odontogenic tumor.

Note: Aggressiveness ranking worth carrying into the exam: AOT and odontoma (essentially inert) < ameloblastic fibroma and CEOT < conventional ameloblastoma and OKC (locally aggressive, recur) < ameloblastic fibrosarcoma and clear cell odontogenic carcinoma (malignant).