Langerhans cell histiocytosis masquerading as acute appendicitis: Case report and review

Isolated Langerhans cell histiocytosis of the stomach: a case report and literature review

Langerhans cell histiocytosis (LCH) is a rare disorder characterized by an abnormal proliferation of pathologic Langerhans cells. The clinical presentation of LCH is highly variable, ranging from a single-system limited disease, to severe, multi-organ diseases with high mortality. LCH usually affects children but very rarely involves adults. The most frequent sites for LCH are the bones, skin, lungs, pituitary gland, and lymph nodes. Gastrointestinal tract involvement by LCH is extremely rare, and only a few cases have been reported. We herein present anIsolated LCH of the stomach in adult. We have reviewed the histologic features and implications of this diagnosis.

Imaging of Histiocytosis in the Era of Genomic Medicine

Histiocytosis describes a group of diseases that have long been considered enigmatic in the history of medicine. Recently, novel genomic analyses have identified somatic oncogenic driver mutations responsible for the pathogenesis of these entities. These discoveries have led to the recharacterization of histiocytoses as neoplastic diseases and have opened a new era of precision medicine approaches for treatment. The histiocytic disorders demonstrate a variety of imaging manifestations involving multiple organ systems, and radiologists play a major role in diagnosis and monitoring. An up-to-date knowledge of the novel genomic discoveries and their implications is essential for radiologists to understand the new approaches to treating histiocytic disorders and to contribute as key members of the multidisciplinary treatment team. This article provides a cutting-edge review of the novel concepts in histiocytosis, with a focus on recent genomic discoveries and precision medicine approaches to treating the disease, and describes imaging manifestations with correlative histologic and genomic findings, with an emphasis on adult-onset cases and uncommon subtypes. ^©RSNA, 2018.