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Sometimes a new cancer can develop, either in the originally affected breast or in the opposite breast. When doctors perform tests on the cancer, they are usually able to tell if this cancer is a new cancer or a recurrence of the original cancer.
A new primary diagnosis means that the cancer is unrelated to your first cancer and so may not behave in the same way. An example of this could be your first cancer being oestrogen receptor positive but your second cancer being oestrogen receptor negative.
When you have a new primary cancer your treatment will depend on which breast the cancer has been diagnosed in. If it is in the same breast as your first cancer, and you previously had a wide local excision and radiotherapy, then a mastectomy may be recommended.
This is because it is not usually possible to give radiotherapy to the same area twice. If the new primary cancer is diagnosed in the other breast then the type of surgery recommended will depend on the size and location of the cancer.
As with your first cancer, your treatment for the new breast cancer will be tailored to your individual situation. This will involve doctors looking at features such as:
You can find our more about how breast cancer is treated here.
Having a second, new diagnosis of primary breast cancer is not in itself thought to affect the overall prognosis (outlook). The individual features of the new cancer (such as the grade and stage) are what will affect this.
Having a new primary diagnosis of breast cancer can come as a shock. Having already had a diagnosis of breast cancer in the past, it might be hard to accept that you have to go through treatment all over again when you thought you had put that part of your life behind you. However, it may feel a little less frightening this time around as you know more about what to expect.
It is important that you have a chance to ask any questions. Your cancer specialist is often the best person to ask as they will be able to give you information that is tailored to your individual situation. Your breast care nurse can also be a great source of information and support.
You might also find it helpful to be in contact with other people who are experiencing something similar.
Our online discussion forums have a separate thread for women who have experienced a new primary diagnosis where you can post and receive messages - click here to visit the forums.