Langerhans cell histiocytosis with anorectal involvement: a rare manifestation of adult disease

Gastrointestinal Langerhans cell histiocytosis with unifocal, single‐system involvement in adults: Cases report and literature review

BACKGROUND

Langerhans cell histiocytosis (LCH) is characterized by unifocal, multifocal single-system, or multi-system disease that occurs in all age groups, while it primarily attacks pediatric patients. Solitary gastrointestinal (GI) LCH in adults is exceedingly rare, so we aimed to investigate GI LCH in adults with unifocal single-system involvement and clarified the clinicopathologic characteristics of this disease.

METHODS

Two cases of solitary GI LCH in adults were presented, and the clinicopathologic features of this diagnosis in the literature were reviewed.

RESULTS

The main diagnostic feature of LCH is the morphologic identification of the characteristic Langerhans cells with prominent nuclear grooves and abundant eosinophilic cytoplasm, accompanied by a variable number of lymphocytes, eosinophils, and plasma cells. The distinctive cells expressed S100, CD1a, and langerin (CD207) on immunohistochemistry. BRAF V600E mutations were detected in the two patients.

CONCLUSIONS

Gastrointestinal Langerhans cell histiocytosis in adults with unifocal, single-system involvement is extremely rare. Most patients were asymptomatic and usually a small solitary polyp in GI tract can be observed under routine endoscopy. Although the overall prognosis of unifocal single-system LCH is favorable, long-term follow-up is still necessary to rule out systemic disease.

Adult-onset perianal Langerhans cell histiocytosis presenting as pruritus ani: a case report and review of the literature

Background

Langerhans cells belong to the histiocytic system and give rise to two tumors: Langerhans cell histiocytosis and Langerhans cell sarcoma. Clinical aggressiveness and degree of atypia distinguish the two neoplasms. Langerhans cell histiocytosis can infiltrate a single or multiple organ systems and particularly affects bone, skin, and lymph nodes. Perianal cutaneous Langerhans cell histiocytosis is a rare condition in adults, with 15 cases reported in the literature.

Case

We present the case of a 50-year-old hispanic man who presented with a 9-month history of pruritus ani and a personal history of diabetes insipidus. Punch biopsy confirmed a lesion of Langerhans cells origin but could not exclude Langerhans cell sarcoma because of limited sample size. An additional biopsy was planned as well as a positron emission tomography scan to determine the extent of disease spread. While the patient failed to follow up for repeat biopsy, the positron emission tomography scan was performed and was negative for metastatic disease. A stable perianal lesion of Langerhans cell histiocytosis with benign clinical features in a 50-year-old male despite lack of treatment is extremely rare and has not been described in the literature so far. Here, we review the presentation and workup of patients with Langerhans cell histiocytosis, review the relevant literature, and discuss treatment planning.

Conclusion

Perianal Langerhans cell histiocytosis is rare, and there should be a high index of suspicion with chronic or new perianal lesions, especially in a patient with a history of diabetes insipidus. It is also important to consider the patient’s full clinical course when it is not possible to reach a definitive pathological diagnosis before management.