[Show abstract][Hide abstract] ABSTRACT: Malignant fibrous histiocytoma was diagnosed in seven cats from biopsy specimens received at the University of Missouri Veterinary Medical Diagnostic Laboratory during a 4-year period from 1987-1991. Tissue blocks from formalin-fixed specimens were resectioned and stained for type I (AE1) and type II (AE3) cytokeratins, desmin, S100 protein, vimentin, and alpha 1-antitrypsin by the avidin biotin peroxidase complex method with diaminobenzidine (DAB) chromogen. None of the tumors stained positively for alpha 1-antitrypsin. Four of seven of the tumors had similar immunohistochemical staining results, with positive staining for type I and type II cytokeratins, desmin, S100 protein, and vimentin. Of the remaining three, one stained positively only for S100 protein and vimentin; one stained positively for vimentin only; and one was negative for all six antigens. Based only on immunohistochemical staining results, three of the tumors could possibly be reclassified: one as a melanoma, one as a probable fibrosarcoma, and one as unknown. These results also indicate that feline malignant fibrous histiocytomas show a diversity of intermediate filament expression, as do human tumors. Our results also do not support the theory that malignant fibrous histiocytomas are of histiocytic origin.
[Show abstract][Hide abstract] ABSTRACT: Forty-four primary feline vaccine-associated fibrosarcomas and 16 recurrences were examined histologically for detailed morphologic characterization with emphasis on tumor grade, presence of neoplastic multinucleated giant cells, presence and proportion of T and B lymphocytes within the tumor, and thin and intermediate filament contents of neoplastic and stromal cells. The microvascularity and proliferation rates of central and peripheral areas of the tumors were also quantified by computerized image analysis. For primary fibrosarcomas, 11 of 44 (25%) were grade I, 21 of 44 (47.7%) were grade II, and 12 of 44 (27.3%) were grade III. The recurrences followed a similar pattern: 4 of 16 (25%) were grade I, 8 of 16 (50%) were grade II, and 4 of 16 (25%) were grade III. A positive correlation was found between the presence of neoplastic multinucleated giant cells and tumor grade. These cells were present in 9 of 12 (75%) of grade III and none of the grade I tumors. Prominent peritumoral lymphoid aggregates or follicles were present in 59% of the tumors, and many contained high proportions of T lymphocytes, varying from 19 to 87%. All fibrosarcomas were immunoreactive for vimentin and 28 of 44 (64%) were reactive for alpha-smooth muscle actin. The actin-positive cells were either part of the tumor or formed a capsule around tumor nodules. The peripheral vascularity was significantly higher than the central vascular density but no difference was found in tumor cell proliferation rates between the two areas. Centrally located, fluid-filled micro- or macrocavitations were frequently observed in the large vaccine sarcomas and probably formed secondary to rapid tumor growth and central necrosis.
[Show abstract][Hide abstract] ABSTRACT: A malignant fibrous histiocytoma (MFH) of the giant cell type was diagnosed in a 10-year-old female Domestic Short-Hair cat. The tumour was surgically removed but recurred after two months and the animal was destroyed. The most prominent histological feature was the presence of numerous multinucleated giant cells scattered among malignant-looking mononuclear tumour cells. In addition, 16 cases of MFH of the giant cell type reported in cats in the English language literature are reviewed. The mean age was 6.5 years. The most often affected breed was the Domestic Short-Hair and no sex preference was found. Ten out of 16 cases were located in the legs; 10 extraskeletal, three were skeletal and in three cases the origin of the tumour was not specified. Proved metastasis occurred in only one case.
Note: Although carefully collected, accuracy of this list of references cannot be guaranteed.
Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.