Langerhans Cell Sarcoma in Two Young Children: Imaging Findings on Initial Presentation and Recurrence
A 17-month-old girl visited our hospital with a chief complaint of intermittent fever that had persisted for the past month, abdominal pain and poor appetite. She was born via normal vaginal delivery with a birth weight of 3.0 kg and had an unremarkable past medical and family histories. Physical examination revealed hepatosplenomegaly and multiple petechiae of the scalp and the lower abdomen. Anemia and thrombocytopenia were noted on blood testing. Upon bone marrow examination, invasion of histiocytic neoplasm was observed.\nContrast-enhanced abdominal CT showed hepatosplenomegaly, periportal low density and multiple small, hypodense-lesions in the liver. Conglomerated lymph node enlargement was found in the porta hepatis, and a huge and heterogeneously enhancing soft tissue mass was observed in the anterior mediastinum (). A biopsy of the mass was conducted extending up to the right supraclavicular region, the scalp, and the abdominal skin lesion. LCS was diagnosed by the malignant cytological features in the lesions, and immunohistochemistry tests that were positive for CD1a, S-100, and CD68. On a follow-up whole-body MRI conducted one year after chemotherapy based on HLH 2004 protocol, the mediastinal mass and lymphadenopathy around the porta hepatis had decreased in size. After 5 months, recurrence on the scalp was suspected, and contrast-enhanced brain MRI and skull base CT showed multifocal osteolytic lesions and enhancing soft tissue lesions in both temporal regions (). A biopsy of the scalp lesion was conducted, and based on positive findings for CD1a and S-100, recurrence of LCS was confirmed before resuming chemotherapy. The patient was treated with 2-CdA and Ara-C combination therapy based on LCH-S-2005 protocol. On follow-up brain MRI obtained one year after treatment, the skull lesion showed improvement. However, on serial ultrasounds of the liver and contrast-enhanced abdominal CT, the volume of the right hepatic lobe gradually decreased, and the caudate lobe and the left hepatic lobe showed hypertrophic cirrhotic morphology. In addition, scattered nodular calcifications were newly formed in the liver parenchyma, and gradually increased in number, spreading along the intrahepatic biliary trees (). The patient is now being followed-up after bone marrow transplantation.