LCH of Bone : Sites
Langerhans Cell Histiocytosis (LCH) of Bone: The most frequently involved bones are the skull, femur, vertebra, pelvis, jaws and ribs. Children younger than 10 years usually have skull or femoral lesions, whereas patients older than 20 years more often have lesions in the ribs, shoulder girdle, and mandible. Small bones of hands and feet are spared.
Lesions of temporal bones, facial bones, sphenoid, ethmoid, and zygomatic are associated with a high risk of diabetes insipidus due to infiltration of pituitary stalk. Orbital lesions can cause proptosis. Temporal bone lesions present with recurrent otitis media or mastoiditis. Vertebral collapse can precipitate neurologic deficits due to spinal cord compression.
Plain xray films supplemented with CT, MRI, and PET scans can render a tentative diagnosis which can be confirmed with FNA cytology or a tissue biopsy.
About this image: 4 y/o female who presented with a limp. Plain x-ray (frontal view) shows ill-defined lucency within the femoral shaft with surrounding layering periosteal reaction. The differential includes LCH and Ewing sarcoma (the latter being less likely because of age). Biopsy confirmed LCH as the diagnosis. Case courtesy of Dr Jeremy Jones, Radiopaedia.org. From the case rID: 8062