Chemotherapy is often part of the treatment of ovarian cancer, either as an adjuvant treatment, for some earlier stages of the cancer, or in more advanced disease, when the cancer has come back or has spread. Many people are worried about the prospect of chemotherapy, particularly because of all the publicity that has been given to possible side effects. Modern chemotherapy and modern ways to avoid or reduce side effects have made chemotherapy much better tolerated than ever before and most people don’t find it as bad as they expected. Nevertheless chemotherapy is still a strong treatment that people would prefer to avoid if they could and when their doctor suggests chemotherapy many people ask what would happen if they didn't have it.

Adjuvant chemotherapy for ovarian cancer is given when surgery appears to have removed all the disease but it is felt that there is a risk of microscopic ceils remaining. In this situation chemotherapy is given after surgery to reduce the chances of the disease coming back. It works by killing off any tiny traces of cancer that might have been left behind after an operation and that were too small to be seen or to be picked up on scans or other tests. By looking under the microscope at the cancer that has been removed (the primary cancer), other organs that were also removed (usually both ovaries, the womb and the fallopian tubes are all taken away at the same time as the tumour) and any lymph glands that were taken away, it is possible for doctors to get an idea of the risk of the cancer coming back. In addition measuring the level of a chemical in your blood, called CA125, can be useful. The chances of an ovarian cancer coming back will vary from person to person but using all this information your doctor should be able to give you a good idea of how likely this is to occur.

If you had a tumour with a very good outlook then the risk of the cancer coming back would be very small. Adjuvant chemotherapy might reduce this risk further, but still not completely guarantee a cure. There would be a benefit from chemotherapy in this situation but it would be small because the chance of doing well without any further treatment is still be very good. On the other hand, if the risk of the cancer coming back was quite high then the chance that adjuvant treatment could reduce that risk and improve the chance of cure would be much greater. A recent research trial of nearly 1000 women with early ovarian cancer confirms this. The trial showed that giving adjuvant chemotherapy, using the chemotherapy drugs cisplatin or carboplatin, improves the survival of women with early stage cancer of the ovary.  

Because it is impossible to know for sure whether or not microscopic traces of cancer may have been left behind, when adjuvant therapy is used there is always a possibility that a woman will already have been cured by the surgery alone and the adjuvant therapy is unnecessary. The problem is that doctors are not able to tell for sure with any individual woman whether or not she needs the treatment.

So it is important that you work out with your doctor what your own particular risk is likely to be, what your chances are of a cure without any adjuvant chemotherapy, and how much the adjuvant treatment is likely to improve things. Once you have that information you can then come to a decision about balancing the possible benefits for you personally against the side-effects of treatment and decide whether or not to have treatment.