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Ovarian cancer

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Grades of ovarian cancer

Grading is a way of classifying ovarian cancer cells based on their appearance and behaviour. To find out the grade of a tumour, a biopsy sample is examined under a microscope. A grade is given based on how the cancer cells look and behave compared with normal cells (differentiation). This can give the healthcare team an idea of how quickly the cancer may be growing and how likely it is to spread.

The grade of ovarian cancer is based on the degree of differentiation of cells and their rate of growth.



grade of differentiation cannot be assessed


well differentiated or low grade – slow growing, less likely to spread


moderately well differentiated or moderate grade


poorly differentiated, undifferentiated or high grade – tend to grow quickly, more likely to spread

Grading plays an important part in planning ovarian cancer treatment and can also be used to help estimate the prognosis (future outcome).


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