Prognosis and survival for soft tissue sarcoma
If you have soft tissue sarcoma, you may have questions about your prognosis. A prognosis is the doctor’s best estimate of how cancer will affect someone and how it will respond to treatment. Prognosis and survival depend on many factors. Only a doctor familiar with your medical history, the type and stage and other features of the cancer, the treatments chosen and the response to treatment can put all of this information together with survival statistics to arrive at a prognosis.
A prognostic factor is an aspect of the cancer or a characteristic of the person (such as age) that the doctor will consider when making a prognosis. A predictive factor influences how a cancer will respond to a certain treatment. Prognostic and predictive factors are often discussed together. They both play a part in deciding on a treatment plan and a prognosis.
The following are prognostic and predictive factors for soft tissue sarcoma.
Size of the tumour
The size of a soft tissue tumour is an important prognostic factor. Tumours that are 5 cm or smaller have a better prognosis than tumours larger than 5 cm.
The grade gives information about how quickly the cancer is growing and how likely it is to spread. The grade is also helpful in determining a prognosis. Low-grade soft tissue sarcomas are linked with a better prognosis because they are less likely to spread (metastasize) or come back (recur) than high-grade sarcomas.
How deep the tumour is
Soft tissue tumours close to the surface of the body (superficial tumours) have a better prognosis than tumours that are growing deep within the body. Tumours that are deep within the connective tissue that wraps around muscles, nerves, blood vessels and organs (called fascia) tend to have a poor prognosis.
Where the cancer started
Soft tissue sarcomas of the arms, legs or surface of the trunk of the body usually have a better prognosis than soft tissue sarcomas that start in other parts of the body.
Type of tumour
Some types of soft tissue sarcoma tend to have a worse prognosis, including malignant peripheral nerve sheath tumours (MPNSTs), leiomyosarcoma, desmoplastic small round cell tumours and epithelioid sarcoma.
The lower the stage of soft tissue sarcoma at diagnosis, the better the prognosis. Stage 4 soft tissue sarcoma (metastatic soft tissue sarcoma) has a poor prognosis. Soft tissue sarcoma that has grown into bone, nerves or vessels usually has a poor prognosis.
Surgery is the main treatment for many soft tissue sarcomas. When a tumour is removed, a margin of heathy tissue around the tumour is also removed. If cancer cells are found in the margin (called a positive surgical margin), there is a poorer prognosis compared to when there are no cancer cells in the margin (called a negative surgical margin).
Surgery to remove the tumour
Surgery is the main treatment for many soft tissue sarcomas. Soft tissue sarcoma that is completely removed by surgery has a much more favourable prognosis than soft tissue sarcoma that is not completely removed or if surgery can’t be done.
People with soft tissue sarcoma who are under the age of 50 tend to have a better prognosis than those over the age of 50.