For breast cancer survivors, factors that increase the risk of a recurrence include:

  • Lymph node involvement. Finding cancer in nearby lymph nodes at the time of your original diagnosis increases your risk of the cancer coming back. Women with many affected lymph nodes have a higher risk.
  • Larger tumor size. Women with a large tumor have a higher risk of recurrent cancer. Women who have very large tumors (more than 5 centimeters, or about 2 inches) — especially if lymph nodes are involved — have a very high risk of the cancer recurring in the same area. These women should talk with their doctors about the role of radiation therapy, even if they undergo a mastectomy.
  • Positive or close tumor margins. When you have an operation to remove a breast lump, the surgeon tries to remove the cancerous lump along with a healthy margin of normal tissue. If the borders of the removed tumor are free of cancer when examined under a microscope, that's considered a negative margin. If any part of the tumor's border has cancer cells (positive margin), or the margin between the tumor and normal tissue is close, the risk of breast cancer recurrence is increased.
  • Lack of radiation treatment following lumpectomy. Women who choose to preserve the breast by undergoing a lumpectomy (also known as "wide local excision") should undergo radiation treatments to the remaining breast to decrease the chance of a local recurrence.
  • Younger age. Younger women, particularly those under age 35 at the time of their original breast cancer diagnosis, face a higher risk of recurrent breast cancer.
  • Inflammatory breast cancer. Women with inflammatory breast cancer face a higher risk of local recurrence, so their treatment typically involves chemotherapy followed by a mastectomy and then radiation to the chest wall.

In recent years, genetic tests designed to predict the risk of breast cancer recurrence have become available. These tests (MammaPrint, Oncotype DX) measure activity in up to 70 genes associated with breast cancer, a process known as gene expression profiling. The results are used to estimate the chance that a woman's cancer will come back. But so far these tests have a very limited role and are applicable only for women with estrogen receptor positive tumors that don't show any sign of spread to the lymph nodes. The tests have been used to plan treatment for primary breast cancer in a very small minority of women. More research is needed to determine whether these genetic tests might prove useful in predicting risk of recurrence on a broader scale.

May. 24, 2011