Bone cancer

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Grading bone cancer

The grade is a description of how the cancer cells look compared to normal cells. To find out the grade of bone cancer, the pathologist looks at a tissue sample from the bone under a microscope. The pathologist gives bone cancer a grade of low or high, 1 to 3 or 1 to 4, depending on the grading system being used. A lower number means the cancer is a lower grade.

Knowing the grade gives your healthcare team an idea of how quickly the cancer may be growing and how likely it is to spread. This helps them plan your treatment. The grade can also help the healthcare team predict future outcomes (your prognosis) and how the cancer might respond to treatment.

How different the cancer cells are is described as differentiation. A 2-grade system uses the following grades:

Low grade means that the cancer cells are well differentiated. They look almost like normal cells. Lower grade cancer cells tend to be slow growing and are less likely to spread.

High grade means that the cancer cells are poorly differentiated or undifferentiated. They look less normal, or more abnormal. Higher grade cancer cells tend to grow more quickly and are more likely to spread than low-grade cancer cells.

There are 2 other grading systems used for bone cancer.

3-grade system
GradeDescription

1

well or moderately well differentiated or low grade

2

poorly differentiated or high grade

3

undifferentiated or high grade

4-grade system
GradeDescription

1

well differentiated or low grade

2

moderately well differentiated or low grade

3

poorly differentiated or high grade

4

undifferentiated or high grade

Stories

Dr Shawn Li I’m extremely grateful to the Canadian Cancer Society for funding my research with an Innovation Grant.

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