splenic histiocytic sarcoma
Saturday 18 May 2013
Definition: Histiocytic sarcoma (HS) is a rare hematopoietic neoplasm, representing as less than 0.5% of all non-Hodgkin’s lymphoma. It is a malignant proliferation of cells presenting morphologic and immunophenotypic characteristics of mature tissue histiocytes.
HS is known to often present as localized disease confined to the intestinal tract, skin, lymph node, or soft tissues, however, primary HS of the spleen has been an exceedingly rare.
It is critical to clearly distinguish HS from other histiocytic processes, from benign to malignant, such as hemophagocytic syndrome, malignant histiocytosis, and acute monocytic leukemia.
Despite that, the detailed evaluation of HS depends especially on the verification of histiocytic lineage and the exclusion of other malignancies, including anaplastic large cell lymphoma, diffuse large B-cell lymphoma, poorly differentiated carcinoma, malignant melanoma, follicular dendritic cell sarcoma, or interdigitating dendritic cell sarcoma, by way of thorough immunohistochemical examination.
HS of the spleen can be potentially lethal condition that might remain asymptomatic or closely related with chronic thrombocytopenia for a long time.
The patients of splenic HS have a poor prognosis due to aggressive behavior with liver or bone marrow infiltration, even though a splenectomy might induce temporary remission.
Therefore, early accurate diagnosis and treatment before disseminated proliferation of the HS tumor cells should improve their survival rates.
Primary splenic histiocytic sarcoma complicated with prolonged idiopathic thrombocytopenia and secondary bone marrow involvement: a unique surgical case presenting with splenomegaly but non-nodular lesions. Yamada S, Tasaki T, Satoh N, Nabeshima A, Kitada S, Noguchi H, Yamada K, Takeshita M, Sasaguri Y. Diagn Pathol. 2012 Oct 17;7:143. doi : 10.1186/1746-1596-7-143 PMID: 23075171 http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3488516/