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Nasal cavity and paranasal sinus cancer

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Grading nasal cavity and paranasal sinus cancer

To find out the grade of cancer, the pathologist looks at a tissue sample from the nasal cavity or a paranasal sinus under a microscope. The pathologist gives the cancer a grade from 1 to 3 or 1 to 4. The lower the number, the lower the grade.

The grade is a description of the differentiation of the cancer cells. Differentiation is how the cancer cells look and behave compared to normal cells.

Low grade means that the cancers 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.

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 how you might respond to treatment.


Brock Taraba Brock has been cancer free for over a decade, thanks to the support we received from the Canadian Cancer Society.

Read Brock's story

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