Langerhans/Dendritic Cell Sarcoma Arising From Hairy Cell Leukemia

• Published in: Clinical lymphoma, myeloma and leukemia Vol. 10; no. 3; p. E39
• Main Authors: Muslimani, Alaa, Boxwala, Iqbal, Nair, Girish B, Blenc, Ann Marie
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 01.06.2010
• Subjects: Hematology, Oncology and Palliative Medicine
• ISSN: 2152-2650; 2152-2669
• DOI: 10.3816/CLML.2010.n.048

Abstract Introduction Langerhans/dendridic cell sarcomas (L/DCS) are rare neoplasms that have rarely been reported to originate from malignant lymphomas. Tumor course can vary from spontaneous regression to aggressive disease. Biphasic progression of hairy cell leukemia to L/DCS has not been previously reported. We describe a case of L/DCS resulting from HCL. Case Report A 66-year-old female, diagnosed in 2000 with HCL (World Health Organization criteria), confirmed by bone marrow biopsy (BMB) and flow cytometry. Flow cytometric evaluation demonstrated a monotypic B-cell population that expressed the classic hairy cell markers CD11c, CD22, CD25, and CD103). The patient was treated with cladribine. After first relapse in 2003, the patient was again treated with cladribine followed by rituximab × 6. After second relapse in 2006, the patient was treated with rituximab × 6. In 2008, splenectomy was performed for massive splenomegaly and showed features of HCL, although the phenotype was not entirely classic at this point. BMB showed a monotypic B-cell population. The patient presented with a left pyriform sinus mass 5 months later that underwent biopsy. Based on histologic and immunophenotypic findings, the tumor was classified as a Langerhans cell sarcoma (expression S100 and CD1a; negative for specific B- and T- cell markers and CD30). Identical clonal immunoglobulin gene rearrangements were identified by polymerase chain reaction (PCR) from the 2003 BMB and pyriform sinus biopsy, which suggests that both the HCL and LCS developed from the same precursor cells. Furthermore, there were similar genetic changes between the 2 tumors, which further supported a clonal relationship between the 2 tumors. The patient was treated with gemcitabine × 3 plus docetaxel. Within 3 months the clinical course was complicated by pancytopenia. In addition, computed tomography showed progression of disease with enlarging mediastinal lymphadenopathy, new pulmonary lesions and retroperitoneal lymphadenopathy. Conclusion This case shows the importance of the biopsy when lesions arise in uncommon areas in patients with HCL. It has been postulated that therapeutic agents might play a role in the development of these tumors. This patient received multiple treatments for HCL. Whether L/DCS in this clinical setting is related to therapy or due to other mechanisms requires further study. While clinical data is limited, our case shows the development of progressive L/DCS in a patient with HCL.