2016 Volume 62 Issue 12 Pages 618-622
Oral focal mucinosis (OFM) is an uncommon disease characterized by mucinous accumulation caused by an overproduction of hyaluronic acid by fibroblasts. Tomich proposed that OFM is the oral counterpart of cutaneous focal mucinosis in 1974. The etiology of the disease is still unclear. We report a case of OFM of the tongue in a 67-year-old man. The lesion was a small white mass of 3 mm in diameter with a smooth surface at the tip of the tongue. The left lower lateral incisor and canine with sharp edges would contact the mass. We clinically diagnosed it as a fibroma and performed tumor extirpation. Histopathological examination showed a well-localized myxoid stroma containing fibroblasts that were positive for vimentin. The stroma was positive on Alcian blue staining, but negative on PAS staining; thus, the presence of hyaluronic acid was suggested. We finally diagnosed this case as OFM. The prognosis after surgery has been favorable, and no recurrence was observed at follow-up after 3 years 3 months.
