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Prognosis and survival for parathyroid cancer
If you have parathyroid cancer, 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 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 your blood calcium level) 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 parathyroid cancer.
Diagnosing parathyroid cancer early is an important prognostic and predictive factor. An early diagnosis of parathyroid cancer, especially before surgery, has a better prognosis. When doctors suspect a parathyroid tumour is cancerous, they can plan for surgery with an en bloc resection. An en bloc resection is the best treatment for most parathyroid cancers.
Complete removal of the cancer
Completely removing all of the parathyroid cancer (called a complete resection) during the first surgery is an important prognostic factor. There is a high risk of the cancer coming back and spreading if the cancer is not completely removed.
The surgeon takes care not to break the covering (capsule) around the parathyroid tumour because if it is broken, cancer cells could spread throughout the neck. This could prevent the surgeon from completely removing all of the parathyroid cancer and increase the risk of the cancer coming back.
Parathyroid cancer often comes back (recurs). Once parathyroid cancer comes back, complete treatment is unlikely and the prognosis is poorer.
Also, treatment of recurrent parathyroid cancer often includes more than one operation. This is associated with a greater chance of complications from surgery and a poorer prognosis.
Cancer cells in blood vessels
Cancer cells can move into nearby blood vessels. This is called vascular invasion. Tumours that don’t have vascular invasion have less chance of coming back and a better prognosis than tumours that do have vascular invasion.
Calcium level in the blood
People with parathyroid cancer and uncontrolled high levels of calcium in the blood (hypercalcemia) have a poor prognosis. People with parathyroid cancer who die from it will probably die from uncontrolled hypercalcemia and its complications.
Abnormal number of chromosomes
Chromosomes are the parts of cells that contain genetic information (DNA). People with parathyroid cancer cells that have an abnormal number of chromosomes (aneuploidy) seem to have a poor prognosis.
The molecules inside the cell that program genetic information. DNA determines the structure, function and behaviour of a cell.