Langerhans cell sarcoma arising from the root of tongue: a rare case.

Langerhans cell sarcoma (LCS), a rare malignant disease with markedly malignant cytological features and poor outcome, originates from Langerhans cells and most commonly affects the lymph nodes, skin, and bone. This paper presents the case of a 58-year-old female with LCS at the root of her tongue, with neither local recurrence nor distant metastasis observed during 47 months of follow up following radiotherapy for more than one month after complete tumor resection. Histological and immunophenotypic tests revealed that the malignant tumor cells were positive for S-100 protein, CD1a, and LCA, and partially positive for CD3ε. By contrast, the tumor cells were negative for langenin, CD30, HMB45, PCK, CK5/6, and P63. Their Ki-67proliferation index ranged from 30% to 40%. This neoplasm was diagnosed as LCS according to the classification of WHO2008. This work is the first report on LCS arising from the root of tongue. This rare case may serve as a reference for future clinical studies.