Abstract:
From the literature results that it can’t be found information, for the canine species, about the
cytomorfological differential diagnosis in the malignant histio-dendritical proliferations. In this paper the authors
want to bring a series of exclusive cytomorphologic arguments for the positive diagnosis and differential diagnosis
of canine malignat proliferations, which have as a proliferative cellular base, the histiocytic cell and the dendritic
cell. In this study we discuss three cytomorphologic forms of malignant proliferations of the histiocytic and dendritic
cell. Two of these forms, the dendritic sarcoma and the histiocytic sarcoma, belong to the malignant lymphoma
category; these are solid tumors localized in the tegument, lymph nodes and spleen. The third histiocytic
proliferation forms is the histiomonocytic leukemia, which belongs to the liquid forms, localized in the hematopoietic
marrow, with permanent cytemic discharge in the peripheral blood. Between the dendritic sarcoma and the
histiocytic sarcoma diagnosis confusions can be created. The differential diagnosis can be made with difficulty on
the histopathological sample, but very easily on the cytomorphological ones. The differences obtained by the
cytomorphological technique, which ensures at the end the differential diagnosis, are generated by two easily
identifiable aspects: the first one consist in the presence of a large cytoplasm with multiple prolongations in
dendritic sarcoma and total absence of this aspect in the histiocytic malignant cellular forms; the second aspect
consists in the presence of a true syncytial cellular pointing out a veritable cytoplasmic mega-anastomosis in the
dendritic sarcoma, and the lack of this aspect in the histiocytic proliferations. Histiomonocytic leukemia differs
fundamentally from any other leukemia cell form by the the existence of a very high cellular polymorphism with cell
gigantism and monstrosities. Finally, we make the assessment that besides the cytomorphological exam, there is no
other methodology of these histiocytic proliferative variants except immunohistochemistry, which is an expensive
and time consuming method. Histopathology can only provide the information that the malignant proliferation have
as a cellular base, the histiocytic cell.
