76. Malignant mesenchymal tumors

Question 1

Fibrosarcoma

Answer 1

Tumour of collagen connective tissue, malignant fibroblasts
Virus-induced in cats (FeSV) sometimes
* young age
* multicentric
* fast and agressive progression

Question 2

Myxosarcoma

Answer 2

Malignant variant of myxoma
Looks almost the same
Rare, in subcutis
Non-encapsulated, many times lobulated
More cell-rich than myxoma

Question 3

Liposarcoma

Answer 3

Malignant tumour of adipose tissue, composed by lipoblasts
Many times lobulated

Question 4

Chondrosarcoma

Answer 4

Unstructured mesenchymal neoplastic cells, chondroid material in matrix
Malignant chondrocytes
Bony tissue can be in the parenchyma (endochondral ossification)

Question 5

Osteosarcoma

Answer 5

Central (productive or non-productive)
Periferal (periosteal or parosteal)

Question 6

Anaplastic sarcomas

Answer 6

Divergent group
Primitive myofibroblast origin? Most frequent in dogs Golden retriever, rottweiler Giant cell type also exists