Histiocytic Sarcoma: A Case Series of Extranodal and Nodal Presentations

Abstract

Introduction: Histiocytic sarcoma is an aggressive malignancy of mature histocytes which often carries a poor prognosis. Histiocytic sarcoma is defined in the World Health Organisation (WHO) classification of histiocytic and dendritic cell neoplasms. Case Presentation: Case 1 depicts a 42 year old Malay gentleman with no premorbids presented to the haematology unit with a three month history of fever, night sweats, unintentional weight loss, left axillary and bilateral inguinal swellings which were progressively enlarging.  Physical examination revealed a medium built gentleman with left axilla, bilateral inguinal lymphadenopathies and hepatosplenomegaly. Excision biopsies of the left axillary and inguinal lymph nodes were compatible with histiocytic sarcoma. He did not have any bone marrow infiltration. He was treated with 6 cycles of CHOP (Cyclophosphamide, doxorubicin, vincristine, prednisolone) polychemotherapy but he subsequently succumbed to severe hemophagocytic syndrome shortly after his 6th CHOP chemotherapy. Case 2 describes a 55-year-old previously healthy Malay gentleman who presented with perianal swelling and weight loss for two months. Physical examination revealed a large perianal swelling measuring 10 cm with bilateral inguinal lymphadenopathies. Anorectal tissue histology was compatible with the diagnosis of histiocytic sarcoma. He underwent a transverse colostomy which was subsequently reversed post-chemotherapy. He completed 6 cycles of CHOP chemotherapy followed by upfront consolidation autologous stem cell transplant. He is currently 9 months in complete remission. Conclusion: Histiocytic sarcoma remains a disease with poor treatment outcomes and high mortality. Understanding the pathogenesis and pathobiology of the disease will provide a future to the development of novel therapies.