Spontaneous Remission of Severe Systemic Langerhans Cell Histiocytosis with Bladder Involvement: A Case Study

Background: The clinical presentation of Langerhans cell histiocytosis (LCH) is heterogeneous ranging from single-organ involvement to systemic disease causing substantial morbidity and mortality. We describe an unusual course of severe multisystem LCH with spontaneous remission. Case Presentation: We report on a 45-year-old Caucasian woman with cervical cancer, FIGO stage IVB. Five months after the end of combined radiochemotherapy and brachytherapy, the patient was readmitted because of severe dysuria. Sterile leukocyturia was seen, and cystoscopy revealed only 3 unspecific small mucosal lesions compatible with postradiation cystitis. Incidentally, a computed tomography (CT) scan of the body showed diffuse micronodular and cystic lesions in lungs and hypodense lesions in the liver. Biopsies revealed infiltrations of CD1a and Langerin (CD207)-positive histiocytes in the lung, liver, and bladder. Additionally, positron emission tomography-CT (PET-CT) was compatible with bone involvement. Retrospective analysis revealed that the increase in alkaline phosphatase might have been a surrogate of bone marrow infiltration with osseous activity. Repeated pneumothoraces occurred, and only one course of vinblastine-prednisolone could be applied. Despite ongoing tobacco consumption and without further therapy, PET-CT showed considerable remission 2 months later. However, despite stable remission, documented by serial PET and conventional CT scans, persistent infiltration of the bladder by Langerhans histiocytes could still be demonstrated 17 months later. Unfortunately, cervical cancer recurred and progressed. Conclusion: Multisystem LCH may rapidly occur, may be oligosymptomatic and, even in high-risk cases, remission without specific therapy might occur. Whether alkaline phosphatase might be a surrogate to monitor osseous disease activity has to be further explored.