Blue nevus: report of a case.

Blue nevus is a benign, acquired melanocytic lesion that typically manifests as an asymptomatic, slate-blue or blue-black, smooth-surfaced macule or papule. It usually measures less than 4 mm in diameter. Intraoral melanocytic nevi are uncommon compared to those found in the skin, with the exception of the blue nevus. The blue nevus is proportionally more prevalent in oral mucosa and represents the second most common form of nevus, accounting for 16.5% to 36% of all oral nevi. The palate is the predominant location for blue nevi, accounting for 87% of all oral cases, although other lesions are found in this region as well. This paper presents a case of common blue nevus of the hard palate in a 76-year-old woman, describes the clinical and histological aspects of the nevus, and discusses the difference between benign and malignant melanocytic lesion in the palate.