Localized Langerhans cell histiocytosis of the stomach treated by endoscopic submucosal dissection

Langerhans cell histiocytosis (LCH) is a rare disease of unknown etiology, characterized by monoclonal cellular proliferation and infiltration of bone marrow-derived Langerhans cells in a single or multiple organs [1]. Isolated involvement of the stomach, however, is an extremely rare phenomenon in LCH [2] [3] [4]. Here we present a case of localized LCH of the stomach with characteristic histopathological findings, which was confirmed and successfully treated by endoscopic submucosal dissection (ESD).

A 51-year-old man was referred to our hospital for the evaluation of a suspected neoplastic lesion of the stomach. There were no subjective symptoms, and the patient denied any past medical history and was not taking any medications. All laboratory findings were within normal limits. Esophagogastroduodenoscopy showed a 5-mm, slightly elevated mucosal lesion in the gastric antrum ([Fig. 1]).

Fig. 1 Gastroscopy showing a 5-mm, slightly elevated mucosal lesion sprayed with acetic acid dye. The lesion was located in the antrum of the stomach.

The endoscopic forceps biopsy specimens from the lesion showed heavy infiltration of histiocytic cells of Langerhans cell phenotype. We then carried out ESD of the lesion for obtaining histopathological confirmation of the diagnosis as well as carrying out local treatment. The retrieved specimen consisted of a well-localized tumor lesion involving the mucosal and submucosal layers ([Fig. 2]).

Fig. 2 Histopathological evaluation of the retrieved specimen obtained by endoscopic submucosal dissection. a Gross view of the resected specimen (28 × 20 mm). b Low-power view showing a well-localized tumor limited to the mucosal and submucosal layers (hematoxylin and eosin, original magnification × 40). c High-power view demonstrating the lamina propria infiltrated with histiocytes of Langerhans cell phenotype, including lymphocytes and eosinophils (hematoxylin and eosin, original magnification × 200).

Immunohistochemical studies revealed diffuse, strong positivity for CD1a and S100 protein within the lesion ([Fig. 3]), but negative staining for cytokeratin.

Fig. 3 Immunohistochemistry revealed diffuse, strong positivity for CD1a (a) and S100 protein (b) on the histiocytic cells (immunohistochemical stain, original magnification × 40).

Following the establishment of the diagnosis of LCH, a comprehensive workup was carried out to determine the extent of the disease, but there was no evidence of multisystem involvement. The patient has remained well during the 12-month follow-up, without local or systemic recurrence.

The treatment of LCH is still controversial, but usually depends on the location of the lesions and the extent of the disease at diagnosis [5]. The present case suggests that complete endoscopic resection and close follow-up is an adequate treatment option for selected patients with small, localized LCH of the stomach.

Endoscopy_UCTN_Code_CCL_1AB_2AD_3AF

References

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• 2 Wada R, Yagihashi S, Konta R et al. Gastric polyposis caused by multifocal histiocytosis X.  Gut. 1992;  33 994-996
• 3 Geissmann F, Thomas C, Emile J F et al. Digestive tract involvement in Langerhans cell histiocytosis. The French Langerhans Cell Histiocytosis Study Group.  J Pediatr. 1996;  129 836-845
• 4 Terracciano L, Kocher T, Cathomas G et al. Langerhans cell histiocytosis of the stomach with atypical morphological features.  Pathol Int. 1999;  49 553-556
• 5 Abla O, Egeler R M, Weitzman S. Langerhans cell histiocytosis: Current concepts and treatments.  Cancer Treat Rev. 2010;  36 354-359