Lipometaplasia in fibrous hyperplasia and inflammatory fibrous hyperplasia of the oral cavity.

Fibrous hyperplasia (FH) is a reactive hyperplastic lesion of the connective tissue, being considered the most common intraoral lesion. The microscopical differential diagnosis of FH/IFH presenting lipometaplasia includes lipoma, notably low-fat/fat-free spindle cell lipoma (SCL), fibrolipoma, and sclerotic (fibroma-like) lipoma, mesenchymal non-lipogenic neoplasms, such as liponeurofibroma and lipomatous perineurioma, and rare disorders such as benign symmetrical lipomatosis (BSL)[[7], [9], [11], [13]] (Figure 2B,C). Only those FH/IFH cases presenting lipometaplasia supported by typical reactive connective tissue stroma were selected. [Extracted from the article]