[Durable remission of Langerhans cell sarcoma attained by autologous hematopoietic stem cell transplantation following surgical resection].

Langerhans cell sarcoma (LCS) is a rare neoplastic proliferation of Langerhans cells with a poor prognosis. Owing to its rarity, standard treatment for LCS has not been established to date. Here, we report a case of LCS occurring in multiple lymph nodes in the right cervix in which remission is maintained by autologous hematopoietic stem cell transplantation (auto-HSCT) after surgical resection. A 58-year-old male presented with enlarged right submandibular lymph nodes. Positron-emission tomography/computed tomography (PET/CT) revealed multiple lymphadenopathies in his right cervix. We performed a lymph node biopsy, and he was diagnosed with LCS. We selected the CHOP regimen as the first-line chemotherapy; however, rapid disease progression was observed soon after the first cycle of the therapy. The neck dissection was performed on day 16 of the CHOP therapy. As the residual tumor was suspected, we started the second-line chemotherapy with a combination of etoposide, cisplatin, ifosfamide, and gemcitabine; complete remission was confirmed by PET/CT. Subsequently, the patient was administered high-dose chemotherapy with auto-HSCT. After 2 years of auto-HSCT, complete remission has been maintained. Although there is no report of auto-HSCT for LCS, it could be an effective therapeutic tool for the disease.