Primary malignant neoplasms can be divided into those that arise from cartilage, those that arise from bone and those that arise from soft tissues. They also include secondary neoplasms.
Cartilage
Malignant cartilage tumours become chondrosarcomata.
Bone cortex
Those that arise from bone cortex become osteosarcoma.
In a young patient they arise from the metaphysis of the bone.
In middle age they are less common, and less malignant, and are periosteal and parosteal osteosarcoma.
In old age and in patients with Paget's disease they are highly malignant and may arise from any part of the Paget involved bone.
Bone medulla
These may become malignant giant cell tumours, Ewing's sarcoma or multiple myeloma
Soft Tissue
A tumour arising from fibrous tissue outside of bone and is called a fibrosarcoma. This type of tumour is usually slow growing, and is resistant to both chemotherapy and radiotherapy.
Malignant fibrohistiocytomata is a much more malignant than fibrosarcoma and faster growing, and arise in the bone itself. The five year survival rate of a malignant histiocytoma is only reported as 40%.
A rhabdomyosarcoma arising from striated muscle is a highly malignant tumour, and is sensitive to both radiotherapy and chemotherapy.
A synoviosarcoma arise from synovial of joints, and is usually fast growing and highly malignant.
A basal cell carcinoma of the skin is precipitated by sunlight, and is locally invasive and slow growing.
A malignant melanoma on the other hand may arise from a preexisting mole or de novo after exposure to sunlight. It is highly malignant and metastasises early.
Although a lipoma is a common benign tumour, a liposarcoma like an angiosarcoma is an uncommon malignant tumour.
Secondary neoplasms spread to bone from carcinoma elsewhere
