Eosinophilic Granuloma of the Skull: A Retrospective Analysis

BACKGROUND: The authors describe 9 cases of children with eosinophilic granuloma (EG) of the skull and report on their clinical manifestations, treatment, and prognosis. METHOD: Nine consecutive patients were diagnosed as EG of the skull and confirmed pathologically between 1996 and 2005. In the present study, multi- and single-system Langerhans' cell histiocytosis without skull involvement were excluded. Patients with EG of the skull were divided into two groups: (1) those with only a single bone lesion and those with (2) multiple bone lesions. Surgical removal was performed between 2 and 10 years of age (mean, 4.2 years). RESULTS: Eight (88.9%) of the study subjects were found to have a single bone lesion at diagnosis, and 1 had multiple bone lesions. Seven patients had a painless skull mass and 2 patients had a painful skull mass. Total removal was performed in all 9 patients. Eight patients received postoperative chemotherapy or indomethacin as adjuvant therapy. Of the 8 patients who received adjuvant therapy, 4 were treated with indomethacin and the remaining 4 received methotrexate-based chemotherapy. Eight patients did not experience EG recurrence, however, 1 patient developed additional lesions 2 years after surgical excision. CONCLUSIONS: EG of the skull is a clinicopathological entity with a good outcome. However, therapies and prognoses are dependent on age at diagnosis and the number of bony involvements.