Diagnosis and treatment of adult Langerhans cell histiocytosis in the rib: a case report and literature review.

Background: Langerhans cell histiocytosis (LCH) is a rare proliferative disease caused by the proliferation of Langerhan's cells and aggregation in multiple organs. Rib involvement is extremely rare and easily misdiagnosed. The biologic behavior of LCH is largely unknown, and it is of utmost importance to differentiate it from tuberculosis and tumors. Herein, we present a male adult diagnosed with Langerhans cell histiocytosis of the rib which was successfully treated with surgery. Case Description: This study retrospectively reports a rare case of rib-only LCH in a 34-year-old male patient who complained of persistent stabbing pain in the left chest and back for 45 days. The pain increased after bending, and was accompanied by chest tightness, shortness of breath, and night sweats. The patient denied any family history of LCH. CT showed an isolated mass on the left chest wall invading the seventh posterior rib. The diagnosis was confirmed by immunohistochemical staining and pathological analysis. The immunohistochemistry showed VIM (+), Ki-67 (+30%), CD1a (+), CD 68 (+) and S-100 (+). After surgical resection, the patient was followed up for more than 5 years without recurrence or complication. In addition, we reviewed and summarized 11 reported LCH cases with rib involvement, in which patients were either asymptomatic, or reported chest or back pain. Surgical resection was the main therapy in each case, and after 4-63 months of follow up, all patients were disease-free. Conclusions: This case presents a rare instance of adult LCH in the rib. Pathological typical Langerhans cells and positive protein S100, CD1a, and CD207 are the key evidences for LCH, and surgical resection is currently an effective therapy with satisfactory outcomes. 2022 Annals of Translational Medicine. All rights reserved.