Stages and Grades of Uterine Cancer
Stage refers to the size and spread of the cancer. Your doctor uses any or all of these tests below to determine the stage of the cancer:
The stage is based on factors such as these:
If the tumor remains confined to the area where it started, it’s called in situ or noninvasive. Cancer cells can break away from the main tumor and start growing in other parts of the body. If it spreads from where it started, even if just to nearby tissues, it’s called invasive or infiltrating.
The process of cancer spreading is called metastasis. Although the cancer has spread to another part of the body, it’s not considered a new cancer. For instance, uterine cancer might spread to the lungs. That is not considered lung cancer. It’s called metastatic uterine cancer.
Uterine cancer that has not spread is called early-stage uterine cancer. Uterine cancer that has spread to other parts of the body is often called advanced-stage uterine cancer.
Grade describes what the cancer cells look like. The grade is used to find out how fast the cells may grow or spread. Your doctor uses the biopsy and samples of your uterus if it is removed to determine the grade of cancer.
A pathologist evaluates the biopsy and assigns a specific grade to the sample. The grade represents how similar the tumor is to normal uterine tissue and includes a description of the different type of cells in the sample. This helps your doctor decide how likely it is that the cancer will spread or return.
Doctors use three grades to describe most uterine cancers. The definitions of the grade are the same whether you have endometrial cancer or uterine sarcoma. The higher the grade, the more likely it is that the cancer may spread.
Grade 1 (low). In this case, 5 percent or less of the tissue sample from a tumor contains cancer cells. The remaining 95 percent of the tissue looks like normal uterine tissue.
Grade 2 (intermediate). Between 6 and 50 percent of the tissue sample from a tumor contains cancer cells.
Grade 3 (high). More than 50 percent of the tissue sample from a tumor contains cancer cells.
Uterine cancer in women with lower grade tumors is less likely to come back after treatment than cancer in women with higher grade tumors.