OUTCOME OF TREATING PEDIATRIC LANGERHANS HISTIOCYTOSIS WITH LCH III IN TERTIARY CENTER, SAUDI ARABIA

Abstract

Background: Langerhans cell histiocytosis (LCH) is a rare disease affects any age and any organ; its presentations and outcome vary from self-healing lesions to life-threatening disseminated disease. This study evaluated the outcome of treating children diagnosed with Langerhans cell histiocytosis (LCH) at Oncology Center, Saudi Arabia.
 Methodology: Through a retrospective study design, the researchers reviewed the medical records and electronic files of all children (aged from 0-≤ 14 years) who had been diagnosed and treated for LCH at Princess Norah Oncology Center (PNOC), King Abdelaziz Medical City, Saudi Arabia, in the period from January 2000 to December 2019 (n=33).
 Findings: Males constituted (66.7%), with remarkable dominance of Saudis (93.9%). The median age at diagnosis was 28 months (IQR=49 months); (42.4%) were diagnosed before reaching their second birthday. Fourteen patients (42.4%) had multisystem (MS-LCH) involvement, of which 13 patients with risk organ (RO) (+) and one patient without risk organ (RO) (-). Most of the patients received LCH III protocols. Reactivation occurred in 11 patients (33.3%), and two deaths (6.1%) occurred in cases with MS (RO) (+) progressive disease. The overall survival was 93.9%; with no statistically significant difference in event free survival observed between patients with multisystem compared to single system involvement.
 Conclusion and recommendations: Excellent outcome of LCH is associated with single system involvement and worse outcome (reactivations, or morality) is determined by multi-organ involvement especially at younger age less than 24 months. Better understanding of pathophysiology and genetic molecular background could lead to a striking transformation to novel therapy that warrants a prospective clinical trial. A high mortality in patients with progressive disease demands an earlier aggressive salvage in such group. Prospective clinical trials are required for improved treatment strategies in these subgroups