Clear cell entities of the head and neck: a selective review of clear cell tumors of the salivary glands.

Clear cell changes may be observed in virtually any benign or malignant tumor of epithelial, mesenchymal, melanocytic and hematopoietic derivation not be attributed to variable etiologies. In general, benign and malignant clear cell neoplasms of the head and neck are rare. They may involve various regions and may be of diverse derivations, with only 1-2% of tumors of the salivary glands, jaws and oral mucosa are primarily or almost exclusively composed of clear cells (Maiorano et al., Semin Diagn Pathol 14:203-212, 1997). This review will selectively discuss the clinicopathological features of salivary gland tumors with clear cell changes, which, at times, may pose a diagnostic challenge and dilemma.