Updated June 18, 2014.

Definition:

Median Survival is a term used to denote how long patients survive with a disease in general or after a certain treatment. It is the time (expressed in months or years) when half the patients are expected to be alive. It means that the chance of surviving beyond that time is 50%. It gives an approximate indication of the survival as well as the prognosis of a group of patients with a cancer.

Median survival is a very commonly used term reported in all cancer treatment studies.

Examples:

'The median survival of patients with stage I follicular lymphoma treated with radiation therapy is 10 years.'

This means that for a particular patient, the chances of living beyond 10 years are 50%.