Breast Cancer Specimens Misdiagnosed: How Accurate Are Your Test Results?

Recent studies have exposed inconsistent and inaccurate results of breast tissues tested for cancer, which has led to the misdiagnosis of cancer. The most troubling aspect is that thousands of women may have failed to receive the proper treatment because of errors in two laboratory tests.

One of these laboratory tests is Her-2, which is used to help determine how aggressive a breast cancer tumor is. The test is done not to diagnose cancer, but to help decide on the proper treatment course once breast cancer has already been diagnosed. If the test is positive then the patient likely has an aggressive tumor that will not only respond poorly to hormone treatment, but to chemotherapy as well.

So these patient will then be treated with Herceptin therapy. Herceptin is an FDA-approved drug that works at slowing the growth of aggressive tumors and at destroying cancerous cells. However, in order to be a candidate for this type of treatment one must first test Her-2 positive because the drug only focuses on Her-2 genes.

The introduction of this drug was a breakthrough- by focusing on a subset of cancer patients the drug was more specific and thereby more effective for its subset. However, because one must first be diagnosed as Her-2 positive before receiving the drug it is crucial that Her-2 testing is accurate. And right now that isn’t the case.

In fact, a 2006 study by researchers at Genentech found that 14% to 16% of patients thought to be positive for Her-2 were actually negative. And 18% to 23% who were diagnosed as negative were actually positive.

Part of the reason for the high incidence of false results is that the test itself is complicated. It depends on the pathologist making judgment calls on the degree of cancer and to subjectively diagnose it. For many pathologists who haven’t been trained or who don’t have a lot of exposure to this particular test it may be difficult to accurately determine the result.

One suggestion to help eliminate these false results is to get a second opinion. Even major insurers will now pay for second-opinion breast-cancer tests. However, oftentimes doctors don’t request second-opinions and the patient is treated based on her initial results.

Alternatively, others have suggested that stricter standards be applied. Because the test result itself can be affected by a wide range of factors, including but not limited to time to fixation, processing, heating, and staining procedures. A more universal standard would help insure that the test is processed in a uniform manner and that there is less variability in the results themselves.

Others have suggested that the sample be sent to labs that are more specialized in performing the Her-2 test. The test is so reliant on the pathologist’s individual interpretation so the more experienced a pathologist is with the specific test then the more uniform and accurate the results.

Either way it is clear that changes need to be made. Otherwise women with breast cancer will continue to be given incorrect treatment which will reduce their chances of beating the cancer. One woman in Boca Raton, Florida, was diagnosed with cancer in 2002 and underwent surgery to remove a tumor from her breast. Pathologists reviewed the tissues from the tumor and found it negative for Her-2. So instead of receiving Herceptin she received chemotherapy and radiation. Several years later she developed pain in her ribs and was told that her cancer had spread to her spine. Not only that, but tests taken of the new cells tested positive on the hormone test. But so did re-testing of her old tumor from 2002. So instead of undergoing chemotherapy and radiation she should have received one of the new medication therapy.

And this is just one example of many where women have received improper treatment based on lab results. The legal implications of these cases involves the misdiagnosis by the pathologist, which the physicians rely on for treatment. But given the variability in test results physicians, such as the oncologist, should also obtain a second opinion before deciding on a treatment plan. There should be safeguards that prevent this from happening in the future because otherwise it is the patient who is made to suffer.

Because far more important than the legal implications of these cases is the effect it has on the lives of these women and their families. Any delay in diagnosing and treating breast cancer can drastically decrease one’s odds of beating it. And that it all could boil down to improper interpretation of test results is inexcusable. Steps need to be taken to insure this stops.

Kreisman Law Offices is experienced in Illinois medical negligence lawsuits and services the entire Cook County area, including Oak Lawn, Wilmette, Evanston, Arlington Heights, Palatine, Vernon Hills, Northbrook, Joliet, Elgin, Mt. Prospect, Downers Grove. Country Club Hills and Alsip.