It is as a rare
soft tissue sarcoma showing two or more distinct types of malignant mesenchymal differentiation.
It is generally
thought that malignant mesenchymomas are high grade sarcomas
with a poor prognosis.
However, low grade malignant mesenchymomas have
been reported which had a better prognosis.
It is essential
to study all areas of the tumour by means of immuno-histochemistry
for an accurate histological diagnosis of malignant mesenchymoma.
Age: Mainly adults.
Site: These tumours are frequently located in the
trunk (for example, the chest wall and retroperitoneum) and
lower extremities (usually on the thigh).
Consists of 3 most
components in malignant mesenchymoma are not dedifferentiated
and other distinct mesenchymal components such as regions of
liposarcoma , chondrosarcoma, and osteosarcoma are neoplastic,
regardless of their histological grades.
tumours with two or more phenotypes- i) Malignant Triton tumours ; ii)
muscle, cartilaginous, or osseous differentiation; iii)
dedifferentiated liposarcoma and iv) dedifferentiated chondrosarcoma.
Soft tissue tumours of uncertain differentiation