What Is the Difference Between a Cancer Diagnosis and Prognosis?

A cancer diagnosis comes before a prognosis. A diagnosis is given by a doctor, after tests have been performed, and will identify what type of cancer a patient may have. Meanwhile, a prognosis is delivered after the diagnosis and predicts the outcome of the disease itself.  

What Is a Cancer Diagnosis? 

Before giving a cancer diagnosis, a doctor will check a patient's medical history, examine them and complete a series of tests to determine what was causing the symptoms. A diagnosis, therefore, concludes that there is cancer present in the body.

The tests will also determine where the cancer is located and what stage it has developed to. Stage 0 means that there is no cancer, stage 1 to 4 however mean there is cancer present. The higher the number, the more the cancer has spread. 

What Is a Prognosis?

A prognosis describes the predicted outcome of the cancer. The prognosis will vary and will depend on the staging of the cancer, family history and the nature of the cancer itself. For example, where it is and what type of cancer it has been determined to be.

Some types of cancers behave differently to others. Some, for example, are more aggressive meaning they tend to be fast growing and may spread to elsewhere in the body. Some cancers, however, may respond well to the available treatments and will therefore have a better prognosis.

In a nutshell, the prognosis gives an idea of how long a patient may live with the diagnosed cancer. In addition, it will encompass the quality of life and symptoms the patient may have in relation to the cancer, as well as if it can be cured or not.

It is important to remember that the prognosis is an informed opinion. It is usually based on a healthcare team's experience and research that has been conducted on a large number of patients over several years. Based on these, health professionals can estimate how different types of cancer behave in most people.

Nonetheless, a prognosis is a tend. Your specific cancer may beat the odds or may have a less favourable outcome than the research shows. When given a prognosis, your health provider may discuss with you the "survival rate" associated with your cancer.

What Does "Survival Rate" Mean?

People often refer to a particular cancer's "5-year survival rate", "10-year" or even "15-year survival rate". This is the percentage of people who will survive their cancer for that particular length of time. For instance, if a patient has been given a 5-year survival rate for cancer with a 50% chance of survival that means 50 out of 100 people who have had that cancer will be alive 5 years following diagnosis.

Though cancer can return, the odds are less likely once the 5-year period has passed. Evidently, the longer a patient survives a cancer diagnosis the more unlikely the cancer will return. It is important to remember that the survival rate of cancer will also depend on several factors - such as, the stage of the cancer, when it is diagnosed, how aggressive the type of cancer is and what treatments are available.

The good news is that cancer survival rates have increased over the past decades, especially in developed countries. This is largely due to early screening, greater understanding of the causes of cancer and new cancer treatment options being available. Chemotherapy, radiation therapy and new technologies alongside combinations of new treatment are all contributing to better survival rates. Cutting-edge technology are also expanding diagnosis and treatment options alongside the many clinical trials currently underway.