Grading bone cancer

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:

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.
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

Grade 1
well or moderately well differentiated or low grade
Grade 2
poorly differentiated or high grade
Grade 3
undifferentiated or high grade
4-grade system

Grade

Description

1

well differentiated or low grade

2

moderately well differentiated or low grade

3

poorly differentiated or high grade

4

undifferentiated or high grade

Expert review and references

  • Gerrand C, Athanasou N, BrennanB, et al . UK guidelines for the management of bone sarcomas. Clinical Sarcoma Research. 2016: 6:7.
  • O'Donnell RJ, Dubois SC, Hass-Kogan DA . Sarcomas of bone. DeVita VT Jr, Lawrence TS, Rosenberg SA. Cancer: Principles and Practice of Oncology. 10th ed. Philadelphia: Wolters Kluwer Health/Lippincott Williams & Wilkins; 2015: 91:1292–1313.
  • Samuel LC . Bone and soft-tissue sarcoma. Yarbro CH, Wujcik D, Holmes Gobel B (eds.). Cancer Nursing: Principles and Practice. 8th ed. Burlington, MA: Jones and Bartlett Learning; 2018: 46:1243-1277.