Chronic health conditions after childhood Langerhans cell histiocytosis: Results from the Swiss Childhood Cancer Survivor Study

Abstract

Abstract Background: Langerhans cell histiocytosis (LCH) is characterized by dysregulated proliferation of LCH cells and subsequent organ infiltration. Clinical manifestations vary and range from a single system unifocal bone disease to multisystem LCH with risk organ involvement. The prognosis is in majority of cases favourable, but some LCH survivors experience chronic health conditions resulting from this disease. Since a comprehensive, population-based description of chronic health conditions among LCH survivors is lacking, we evaluated the spectrum and prevalence of chronic health conditions among LCH survivors compared with siblings of childhood cancer survivors and identified factors associated with chronic health conditions. Results: In total, 123 LCH survivors participated (response rate 69%). Median time since diagnosis was 13 years (interquartile range 9–20) and median age at study was 20 years (interquartile range 15-26). LCH survivors were more often male (63%). We also included 866 siblings of childhood cancer survivors as a healthy comparison group. Fifty-nine percent of LCH survivors had at least one chronic health condition while only 48% of siblings had one or more chronic health conditions (p=0.02). Cardiovascular (13% vs. 6%), endocrine (15% vs. 1%), musculoskeletal (22% vs. 12%), and digestive (15% vs. 8%) chronic health conditions were more common among LCH survivors than siblings. Among survivors of single system unifocal bone LCH, only musculoskeletal (23% vs. 12%) CHC were more prevalent compared with siblings. Among survivors of all other LCH forms, neurological (40% vs. 23%), endocrine (24% vs. 1%), musculoskeletal (21% vs. 12%), digestive (21% vs. 8%), and cardiovascular (18% vs. 6%) chronic health conditions were more prevalent compared with siblings (all p<0.05). Factors most strongly associated with occurrence of chronic health conditions were multisystem LCH, multifocal bone involvement, and involvement of pituitary gland. Conclusions: We showed more than half of long-term LCH survivors suffered from at least one chronic health condition and were affected considerably more than siblings. Clinicians in paediatric cancer survivorship programs should be vigilant regarding musculoskeletal, endocrine, digestive, and cardiovascular chronic health conditions in multisystem LCH, multifocal bone disease survivors, and those with pituitary gland involvement.