If invasive breast cancer cells are present, the diagnosis is no longer DCIS, and your doctor will order more tests to find out whether your cancer has spread and to help determine your treatment. Some of these will probably include: chest X-ray, blood tests, and tumor marker tests (estrogen-receptor and progesterone-receptor status, Her-2-neu). Sometimes, additional studies such as a bone scan or computer tomography (CT), or PET (Positive Emission Tomography) will be ordered. Unfortunately there is no test that can completely reassure a woman that her cancer has not spread. These additional studies are done based on risk for metastatic disease, large tumor size, high grade and multiple involved lymph nodes.
The HER-2-neu (pronounced "her-to-new") test is not necessary for routine evaluation of noninvasive breast carcinomas. However, there are reports that DCIS that has high levels of HER-2-neu, like high-grade DCIS, may be more likely to recur and invade the breast.
With removal of all the DCIS and a thorough investigation of the tissue by a pathologist, very few women diagnosed with DCIS die of breast cancer. Neither radiation treatment nor tamoxifen has been found to increase a woman's already excellent survival rate after a diagnosis of DCIS. The major benefits of proper treatment of DCIS are a reduction in the odds of DCIS recurring in the breast and a reduction in the odds of developing an invasive breast cancer from DCIS. Because either of these events could result in the loss of the entire breast, breast preservation is also a goal of DCIS treatment.
You are less likely to have a recurrence in the same breast after a diagnosis of DCIS if your treatment includes: