Table of Contents
Definition / general | McCune-Albright syndrome | Symptoms | Radiology description | Microscopic (histologic) description | Microscopic (histologic) imagesCite this page: Pernick N. Fibrous dysplasia. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/mandiblemaxillafibrousdysplasia.html. Accessed September 21st, 2023.
Definition / general
- Called craniofacial form of fibrous dysplasia if confined to jaw
- Monostotic, polyostotic or associated with McCune-Albright syndrome
- May be congenital or hereditary (but differs from cherubism)
- Starts in childhood, usually diagnosed by age 20 years
McCune-Albright syndrome
- Due to somatic mutation of c-fos oncogene that causes activation of cAMP pathway
- Polyostotic fibrous dysplasia, cafe au lait skin pigmentation (large, dark lesions with serpiginous ["coast of Maine"] borders in chest, neck, back), almost exclusively in women
- Also endocrine abnormalities (precocious puberty, hyperthyroidism, pituitary adenomas that secrete growth hormone primary adrenal hyperplasia)
Symptoms
- Unilateral painless swelling of mandible or maxilla in men / women ages 25 - 35 years
- No treatment since growth is self limited and responsive to pubertal hormonal changes
- Surgical recontouring performed if facial deformity, although may regrow in 25%
Radiology description
- Ill defined margins
- Diffusely radiopaque with ground glass image
Microscopic (histologic) description
- Uniformly distributed C shaped or Chinese figure-like trabeculae of woven / immature bone within proliferating fibroblastic and vascularized stroma
- Usually no osteoblastic rimming and no / rare osteoclasts
- Growing collagen (Sharpey's fibers) may form perpendicular to the sites of bone formation but are not essential for diagnosis (Oral Dis 2017;23:697)