Langerhans Cell Histiocytosis of the Gastrointestinal Tract: Evidence for Risk Organ Status.

OBJECTIVE: To investigate the "risk status" of Langerhans cell histiocytosis (LCH) of the gastrointestinal tract.

STUDY DESIGN: Outcomes from 43 published cases of patients with LCH and gastrointestinal tract involvement were matched to 43 patients with LCH without gastrointestinal tract involvement cared for at our institution. Comparisons were made of the 5-year overall survival rates determined from Kaplan-Meier survival curves for the entire cohort of patients, as well as subgroups defined by lack of risk organ involvement and later era of treatment (to control for temporal changes in LCH treatment regimens). In addition, an association between LCH-gastrointestinal tract and risk organ involvement was investigated.

RESULTS: The 5-year overall survival for children with LCH-gastrointestinal tract (45.3%) was significantly worse than for those without gastrointestinal tract involvement (94.6%; P = .001). This difference remained significant after we excluded risk organ involvement (53.6%% vs 100%; P = .001), and analyzing subjects diagnosed after 2000 (75% vs 100%; P = .012). A 4-fold increase in risk organ involvement with LCH-gastrointestinal tract was observed (OR 4.359; 95% CI 1.75-10.82, P = .001).

CONCLUSIONS: This limited retrospective study suggests that patients with LCH-gastrointestinal tract involvement may have decreased survival, independent of risk organ involvement, and provides evidence to support a prospective study to evaluate risk organ status of LCH-gastrointestinal tract. LCH-gastrointestinal tract may be associated with a 4-fold risk for risk organ involvement. Attention to gastrointestinal symptoms and LCH-gastrointestinal tract in young children diagnosed with LCH is warranted.