Solitary oral fibromas of the tongue show similar morphologic features to fibrous papule of the face: a study of 31 cases.

The morphologic similarities between fibrous papules of the face and multiple oral fibromas were mentioned long ago, mainly in the context of phakomatoses. Both lesions have been considered to be different types of angiofibromas. Nonetheless, this interpretation is not accepted by all authors. We tried to investigate if solitary oral fibromas also share morphologic features with fibrous papules of the face. For this purpose, we designed a retrospective study retrieving 31 fibromas of the tongue from 30 different patients and studied a control group of 20 fibrous papules of the face from 20 different patients. From the oral fibromas, 15 lesions presented as dome shape, whereas 16 lesions presented as polypoid. Lesion size varied between 2 and 7 mm. In all the lesions, we found a common pattern: a fibrous and collagenized stroma, with prominent vessels. Inflammatory infiltrate was mild. Also, we specifically searched for 4 morphologic features: dilated blood vessels, concentric perivascular fibrosis, multinucleated cells, and mast cells. Multinucleated cells and dilated blood vessels were a common feature. On the contrary, concentric perivascular fibrosis was not a prominent feature. Thick collagen bundles (keloid like) were also occasionally found. Mitoses were rare. These findings were similar to the ones described in fibrous papules of the face, which were also present in our control group of 20 fibrous papules. Therefore, we conclude that the sporadic type of fibroma shares many morphologic features with the fibrous papules of the face. This would be similar to the morphologic relation, already described, between fibrous papules of the face and oral fibromas of phakomatoses.