Massive macronodular juvenile xanthogranuloma of the eyelid in a newborn.

A newborn baby with a lump on his right upper eyelid that was unresponsive to warm compresses and oral antibiotics presented at 3 weeks of age with a yellow mass measuring 20 mm in diameter at the base. Preliminary diagnosis was benign choristomatous mass; and warm compresses were continued. The mass continued to enlarge and 5 weeks later was 35 mm, with a tight, atrophic overlying epidermis and greater pupillary occlusion. Concern for possible malignancy prompted surgical resection and reconstruction with a supraclavicular graft. Histopathology disclosed that the eyelid tissue was nearly completely replaced by a highly cellular histiocytic neoplasm with prominent eosinophilic, often foamy cytoplasm, and nuclear pleomorphism. Poorly formed Touton giant cells were found. The mass showed positive immunoreactivity, with histiocytic markers CD163 and factor XIII, and was negative for cytokeratin markers, smooth muscle actin, and desmin. These features were compatible with JXG.