Histiocytic sarcoma in dogs

Abstract

Canine histiocytic sarcoma (CHS), also known as malignant histiocytosis is a very aggressive hematologic malignancy that has a high metastatic rate and mortality rate. CHS originates from white blood cells, namely histiocytes that commonly reside in soft tissue and connective tissue throughout the body. Microscopically, the cell morphology of this tumor sometimes is indistinguishable from other round cell tumors and carcinomas by using routine hematoxylin and eosin staining. Currently, immunohistochemistry is a valuable diagnostic tool for identifying types and cell of origin of the tumor that most CHS cells have dendritic cell immunophenotype (CD18+, CD11c+, MHCII+, CD11d-). The most currently available treatments for CHS are the combination of surgical excision, radiotherapy and chemotherapy, known as multimodal therapy, in order to increase treatment efficacy and survival time of dogs with CHS. Furthermore, the palliative treatment should be considered in CHS cases to improve the quality of life.