Langerhans cell sarcoma arising from chronic lymphocytic lymphoma/small lymphocytic leukemia: Lineage analysis and BRAF V600E mutation study

• Authors: Weiwei Chen, State University of New York at Buffalo; Ronald Jaffe, University of Pittsburgh Medical Center; Linsheng Zhang, Emory University; Charles Hill, Emory University; Anne Marie Block, Roswell Park Cancer Institute; Sheila Sait, Roswell Park Cancer Institute; Boer Song, State University of New York at Buffalo; Yunguang Liu, State University of New York at Buffalo; Donhong Cai, State University of New York at Buffalo
• Journal Title: North American Journal of Medical Sciences
• Volume: Volume 5, Number 6
• Publisher: Medknow Publications | 2013-06-01, Pages 386-391
• Type of Work: Article | Final Publisher PDF
• Publisher DOI: http://doi.org/10.4103/1947-2714.114172
• Subjects: Health Sciences, Oncology; Health Sciences, Medicine and Surgery

Abstract

Background: the phenomenon that histiocytic/dendritic cell sarcomas may be transformed from lymphoproliferative diseases is dubbed 'transdifferentiation'. Langerhans cell sarcoma (LCS) transdifferentiated from chronic lymphocytic leukemia/small cell lymphoma (CLL/ SLL) is extremely rare. The underlying mechanisms of LCS tumorogenesis and its transdifferentiation from CLL/SLL are largely unknown. Aims: the authors strive to further characterize LCS, to understand the potential molecular changes in LCS and the underlying mechanisms of CLL/SLL transformation to LCS. Materials and Methods: a progressively enlarging right inguinal lymph node from a 68-year-old female patient with a history of CLL was biopsied and submitted for flow cytometry analysis, routine hematoxylin, and eosin (H and E) stain and immunohistochemical study. Furthermore, clonality study (fluorescent in situ hybridization (FISH) analysis with a CLL panel probes) and BRAF V600E mutation study (pyrosequencing and immunostain) were performed. Results: two different neoplasms, LCS and CLL/SLL, were discovered to occur simultaneously in the same lymph node. These two entities were shown to be clonally related. More importantly, for the first time, BRAF V600E mutation was detected in LCS. Conclusions: LCS can be transdifferentiated from CLL/SLL and BRAF V600E mutation may provide the foundation for alternative therapy of LCS.