Clear cell odontogenic tumor--a new histologic variant with aggressive potential.

This report delineates the clinical and laboratory findings for a previously unreported neoplasm of putative odontogenic origin. We describe the clinical, radiographic, operative, histologic, histochemical, and ultrastructural findings of the tumor in three women. All lesions were centrally located in the jaw bones, were expansile, and, except for mobile teeth and/or jaw enlargement, exhibited few symptoms. Radiographically, there was bone and tooth destruction resulting in poorly delineated margins. Microscopically, the tumors were nearly identical in that they consisted primarily of large sheets and islands of uniform vacuolated and clear cells without evidence of amyloid deposition, calcification, or glandular differentiation. One of the lesions recurred 1 1/2 years after removal without evidence of metastasis. The results, based only on these cases, suggest that this is a locally aggressive neoplasm of odontogenic origin. Casual microscopic examination of this rare neoplasm could result in misdiagnosis as a metastatic clear cell neoplasm, especially renal cell carcinoma.