Langerhans cell histiocytosis: retrospective evaluation of 123 patients at a single institution.

The aim of this study was to retrospectively evaluate clinical characteristics at diagnosis and outcome of patients with Langerhans cell histiocytosis (LCH). From October 1987 to March 1996, 133 patients with confirmed LCH were admitted to Hospital JP Garrahan in Buenos Aires (123 evaluable). Median age was 5 years (range 15 days to 18 years). Initial organ involvement included bone 114 patients, ear 34, skin 30, liver 18, lung 14, lymph nodes 14, spleen 12, diabetes insipidus 9, and bone marrow 2. Nineteen patients had organ dysfunction, pulmonary 14, hematological 14, and hepatic 12. Two groups were defined: Group A included patients with single system disease (uni- or multifocal) and group B multisystem (with or without organ dysfunction). In group A (n = 82), 24 patients were treated with chemotherapy (prednisone and vinblastine), 21 with surgery, 15 received radiotherapy, and 22 were only observed. Patients of group B (n = 41) were treated with chemotherapy consisting of prednisone and vinblastine, DALHX 83, or LCH1-based chemotherapy. At a median follow-up of 3 years (range 1 month-8 5/12 years) 93% of patients of group A and 39% of group B survive free of reactivation. In group B, 22% had a reactivation and 39% died of progressive disease. Sequelae were detected in 35 patients (28%), which included diabetes insipidus in 17, hearing loss in 13, bony sequelae in 11, sclerosing cholangitis in 6, and lung fibrosis with bullae in 6. Two patients had a subsequent malignant disease. A total of 17 (14%) patients died and 16 of them belonged to the group B: 13 died of progressive disease, 2 due to sclerosing cholangitis (with sepsis in one case and encephalitis in the other one), 1 with progressive disease and associated myelofibrosis, and 1 patient of group A with active disease and brain stem tumor. Patients who had organ dysfunction had a reactivation free survival of 32%. All these patients survived with sequelae. Logistic regression analysis showed that organ dysfunction and hematological involvement had significant predictive values in relation to death. Patients of group A had an excellent survival rate, whereas in those of group B a high mortality was found, especially in the subgroup of patients with organ dysfunction. Lahey's criteria should be revised. Sequelae were also more common in this group.