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Gastrointestinal Tract Langerhans Cell Histiocytosis:A Clinicopathologic Study of 12 Patients
Am J Surg Pathol 2011;35:305–310
Abstract: Gastrointestinal (GI) tract involvement by Langerhans
cell histiocytosis (LCH) is a rare condition. It is typically noted in
male patients with systemic disease and is associated with both
poor prognosis and high morbidity. The incidence peaks in
childhood. However, a limited number of cases have been reported
in adults. To further characterize this disease process, we collected
24 cases of GI tract LCH from 12 patients. The patients included 2
children (4mo and 2.3 y) and 10 adults (40 to 77 y; mean, 58.4 y),
with a female predominance (9 of 12, 75%). Both children presented
with failure to thrive, bloody diarrhea, and anemia. In
contrast, 5 of 10 (50%) adults were asymptomatic and the rest had
unrelated symptoms. Endoscopically, the pediatric patients showed
the involvement of the duodenum and multiple colonic sites.
However, 8 of 10 (80%) adults presented with a solitary polyp,
primarily involving the colorectum (7 of 8, 88%). The lesions
ranged in size from 0.1 to 0.8cm (mean, 0.4 cm), and were predominantly
intramucosal (18 of 24, 75%) with either a marginated
(14 of 24, 58%) or infiltrative (10 of 24, 42%) growth pattern.
Microscopic features were similar to those of LCH found
elsewhere, although some cases differed by showing prominent
lymphocytes (12 of 24, 50%) rather than eosinophils and large
nucleoli (2 of 24, 8%). Reactive overlying mucosal and entrapped
epithelial changes (10 of 24, 42%), mucosal ulceration (3 of 24,
13%), focal necrosis (1 of 24), and multinucleated giant cells (1 of
24) were also identified. Mitotic figures were absent. On immunohistochemistry,
all lesions expressed the S-100 protein and
CD1a. Follow-up information was available for 11 (92%) patients
ranging from 2 months to 5.3 years (mean, 1.8 y). One pediatric
patient was lost to follow-up. However, the other patient
developed multisystem disease and died 1 year after the initial
diagnosis. Two adult patients developed cutaneous disease, 2
months and 2 years after the initial diagnosis, 1 of whom had
multifocal colonic disease. On the basis of this study, GI tract
LCH lesions present in both children and adults with a female
predominance. Consistent with earlier reports, pediatric cases are
associated with systemic disease and poor prognosis. However, in
adults, LCH is typically encountered as an incidental, solitary
polyp. Rare cases of systemic disease may occur and, therefore,
close follow-up may be warranted.

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