Langerhans Cell Histiocytosis: Single Center Experience of 25 Years

To review a single center outcome of patients with Langerhans Cell Histiocytosis diagnosed at a tertiary referral hospital from Turkey.Methods: The files between 1989 and 2015 of 80 patients with LCH were retrospectively analyzed.

During the 25 years, 80 patients were diagnosed with LCH. The median age at diagnosis was 53 months (2-180 months) and the median follow-up time of patients was 10 years and 9 months (24 months-25 years). Bone was the most frequently affected organ (n:60, 75%). Initially, 43 patients (54%) had single system (SS) disease, 20 patients (25%) had multisystem (MS) disease without risk organ involvement (MS-RO^-), and 17 patients (21%) had a multisystem disease with risk-organ involvement (MS-RO⁺). The overall survival (OS) rate was 91%, and event-free survival (EFS) rate was 67% at 10 years. 10-year OS rate was lower for patients with MS-RO⁺ (65%) when compared to those with, MS-RO^-, and SS (100%, 97%, p value=<0.001). The overall survival rate was also lower in patients with lack of response to systemic chemotherapy on 12th week (p=<0.001), younger age (<2 years) at presentation (p=<0.02), skin involvement (<0.001) and lack of bone lesions at presentation (<0.001).

In the group with MS-RO⁺, OS is significantly low compared to other groups. Further efforts are warranted to improve survival in MS-RO⁺ patients.