What do 'grade' and 's-phase' mean?

'Grade' means how similar the cancer cells are to normal cells of the same type. For example, how like normal breast cells your breast cancer cells appear when they are examined under a microscope. Grade can be described as high or low. Or it may be given a number, usually 1 to 4 - the lower the number, the lower the grade. Low grade cancer cells look most like normal cells. High grade cancer cells look least like normal cells.

The grade gives your doctor some idea of how the cancer might behave. High grade cancers may be faster growing, or more likely to spread. For many types of cancer, your treatment may be different depending on whether you have a high or low grade cancer. For example, you are more likely to be offered chemotherapy after surgery for breast cancer if you have a high grade cancer, even if there is no sign that the cancer has spread.

'S-phase' is short for synthesis phase. Cells go through different phases each time they divide and multiply. S-phase is the part of the cycle when the cells make a copy of their DNA so that each new cells has a full set of genes. They 'synthesise' DNA just before the begin to divide.

The doctors look at the proportion of cells in s-phase in cancer tissue when they examine it in the laboratory. This gives them an idea of how active the cancer is. The more cells that are in s-phase, the more are dividing, so the faster the cancer will grow.

There is more about genes and cancer in the about cancer section of CancerHelp UK.