ON THIS PAGE: You will learn about how doctors describe the growth and spread of DIG. This is called the grade. Use the menu to see other pages.
Stage and grade describe where a tumor is located, if it is likely to spread, if or where it has spread, and whether it is affecting other parts of the body. Doctors use diagnostic tests to find this information, so the diagnosis may not be complete until all of the tests are finished. Knowing this information helps the doctor to decide what kind of treatment is best and can help predict a patient's prognosis, which is the chance of recovery.
Usually, there are different stage descriptions for different types of tumors. However, there is no standard staging system for DIG. Instead, DIG is usually described by grade (see below).
The grade describes how much the tumor cells look like healthy cells when viewed under a microscope. The doctor compares the tumor tissue with healthy tissue. Healthy tissue usually contains many different types of cells grouped together. The tumor’s grade may help the doctor predict how quickly it will grow and spread. In general, the lower the tumor’s grade, the better the prognosis.
If the tumor looks similar to healthy tissue and has different cell groupings, it is called "differentiated" or a "low-grade tumor."
If the tumor looks very different from healthy tissue, it is called "poorly differentiated" or a "high-grade tumor."
In its classification system for central nervous system tumors, the World Health Organization (WHO) classifies DIG as a grade I tumor. This grade I tumor classification group includes distinct, unconnected tumors that are less likely to spread. In addition, a grade I tumor classification means it can often be successfully treated with surgery to remove the tumor. (Surgery and other treatment types are discussed more in the next section.)
A recurrent tumor is a tumor that has come back after treatment. If the tumor does return, there will be another round of tests to learn about the extent of the recurrence. These tests and scans are often similar to those done at the time of the original diagnosis.
Information about the tumor will help the doctor recommend a specific treatment plan. The next section in this guide is Types of Treatment. Use the menu to choose a different section to read in this guide.