Multifocal, Multisystem Presentation of Adult-Onset Langerhans Cell Histiocytosis on 18F-Fluorodeoxyglucose Positron-Emission Tomography–Computed Tomography

Abstract

Langerhans cell histiocytosis (LCH), also known as histiocytosis X, is a rare systemic disorder arising from clonal proliferation of immature CD207-positive (langerin) myeloid dendritic cells (histiocytes) in the skin and visceral organs with a tendency to involve single or multiple organ systems with variable clinical course and prognosis. The incidence of LCH is very less in adult and occurs almost exclusively in children. Genital, perianal, and lung lesions are considered to be rare manifestations of adult LCH. We describe a case of 31-year-old, nonsmoker female who presented in February 2020 with itching and burning sensation in perianal and vulvar regions accompanied with multiple nonhealing ulcers and papillomatous lesions. These lesions gradually increased in size with no response to antibiotics and topical steroids. She was advised positron-emission tomography– computed tomography (PET-CT) scan for further evaluation. After PET-CT scan, her provisional diagnosis of multisystem, multifocal Langerhans cell histiocytosis with high-risk organ involvement was made. Both vulvar and perianal lesions were biopsied which was suggestive of Letterer–Siwe variant of LCH. The prognosis of this variant is very poor even with aggressive chemotherapy and 5-year survival rate of only 50%. Hence, it requires careful consideration during diagnosis and management.

A challenging diagnosis of Langerhans’ cell histiocytosis with hypothalamic-pituitary and mandibular involvement: case report and literature review

“…In the first eight patients followed up, AVP deficiency was consistently the first hormonal deficiency observed and the last one presented with a primary infertility 13 . In one patient, AVP deficiency remained the sole endocrine abnormality 2 , whereas the majority of patients eventually developed at least one deficiency in an anterior pituitary hormone 1 , 8 , 11 , 14 . Similar findings have been reported in a series of seven cases in which, APD predominantly coexisted with AVP deficiency 17 .…”

“…Langerhans cell histiocytosis (LCH), previously known as histiocytosis X (HX) or Hand-Schuller-Christian syndrome 1 , is a rare abnormal clonal proliferation of myeloid dendritic cells (histiocytes or Langerhans cells) in the skin and visceral organs, which are immature, CD207 (langerin)-positive cells, derived from the bone marrow 2 . LCH is more common in childhood and rare in adults, with a predicted incidence of 1–2 cases per million and a peak prevalence between the ages of 20 and 35 years 2 , 3 . Yet the true incidence might be higher as it is commonly misdiagnosed 4 .…”