17 percent of D.C.I.S. cases identified by a commonly used needle biopsy may be misdiagnosed.
Far too many women know the horror of discovering a breast lump and then waiting for the verdict. Do I have cancer, they wonder? Will I live? Unfortunately, getting a diagnosis may not end the anxiety. According to a recent article in the New York Times, doctors regularly misdiagnose a type of breast cancer called ductal carcinoma in situ, or D.C.I.S., particularly in its earliest stages. The article claims, “17 percent of D.C.I.S. cases identified by a commonly used needle biopsy may be misdiagnosed.”
The article quotes Dr. Shahla Massood, the head of pathology at the University of Florida College of Medicine in Jacksonville as saying that the diagnosis of D.C.I.S. “is a 30-year history of confusion, differences of opinion and under- and over-treatment. There are studies that show that diagnosing these borderline breast lesions occasionally comes down to the flip of a coin.”
Even the definition of D.C.I.S. is controversial. According to the Medicinenet.com website, D.C.I.S. is a precancerous condition in which “malignant cells” are found in the lining of a breast duct without any evidence of having spread beyond. Medicinenet also claims that, “DCIS is clearly the precursor (forerunner) of invasive breast cancer.”
The Mayo Clinic has a slightly different viewpoint. “Ductal carcinoma in situ (DCIS) is considered the earliest form of breast cancer,” says its literature. “In DCIS, abnormal cells multiply and form a growth within a milk duct of your breast. DCIS is noninvasive, meaning it hasn’t spread out of the milk duct to invade other parts of the breast.”
The National Cancer Institute offers yet another take. According to their website, “In some cases, DCIS may become invasive cancer and spread to other tissues, although it is not known at this time how to predict which lesions will become invasive.” In other words, although D.C.I.S. is characterized by the appearance of “abnormal” cells in the lining of breast duct, what happens from there is unpredictable.
So just which opinion hits the mark? Is DCIS the “precursor of invasive breast cancer,” or “invasive “in some cases,” or “noninvasive”? The problem with DCI S clearly extends beyond misdiagnosis to questions about just what is being diagnosed. All this adds up to a lot of anguish and confusion for women who do get a positive DCIS diagnosis that leaves them wondering how scared they should be and how they should proceed.
And why is diagnosis so inaccurate? CBS news correspondent Dr. Jennifer Ashton says that the difficulty diagnosing D.C.I.S. has several causes. First, as I’ve written before, mammography is far from perfect. “It can see things there that are not cancer and it can miss cancers that are there.” Diagnosis has gotten increasingly difficult over the past three decades as mammograms continue to turn up lesions that are smaller and smaller.
Next, the biopsy process is prone to error. In biopsy, a sample of tissue from the affected area is removed and studied microscopically by a pathologist. The level of the pathologist’s skill and experience, the quality of the sample, and other factors contribute to the accuracy of the diagnosis. In fact, the New York Times article highlights the case of a woman who was misdiagnosed as positive for D.C.I.S. and later found out that, in all likelihood, she never had the disease — and this after undergoing partial mastectomy, radiation, chemo, and tremendous emotional and psychological stress. Let that stand as evidence of the importance of getting second, third, and maybe even fourth opinions!
Finally, the controversy around defining D.C.I. S. makes diagnosing it that much more difficult. Even worse, it makes prescribing a medical treatment plan nearly impossible. Some experts believe that the disease does not require early treatment because it doesn’t necessarily become invasive. Others claim that D.C.I.S. is definitely invasive and should be treated immediately.
Interestingly, the Doctors Company, a malpractice insurance company for doctors, states in its loss prevention guidelines on breast biopsy and fine needle aspiration, that a large percentage of their misdiagnosed cases relate back to biopsy. According to its review of 218 cases, “Fifty-four percent of breast biopsy claims involved the false-negative diagnosis of breast carcinoma, while 35 percent were for the false-positive diagnosis of carcinoma.” Translated, that means a lot of women either didn’t get appropriate treatment, or were treated needlessly. Even more problematic, of all the malpractice claims handled by the company, a full 22 percent involved “breast specimens” — samples taken from a variety of procedures for diagnosing breast conditions.
I’ve written previously about how mammograms miss up to 30 percent of all tumors, and may deliver a false positive diagnosis as much as 90 percent of the time. On top of that, there’s the radiation exposure to worry about. Biopsy, the backup procedure used to verify the findings of a mammogram, clearly isn’t foolproof either, particularly in early D.C.I.S. cases.
So what should women do to ensure they get an accurate diagnosis? First, remember that there are alternatives to mammography that don’t involve radiation exposure. Thermography is relatively cheap, safe, and effective. Breast sonograms also provide a safer, relatively inexpensive alternative, and according to the American Journal of Radiology, sonography detects twice as many cancers as mammography. Plus, there’s a new imaging technology called elastography, which when used in conjunction with sonography not only finds tumors, but also reveals if they’re cancerous…without biopsy. Next, inquire about the experience of your pathologist. The doctor accused of misdiagnosing the woman in the New York Times article said he read only about 50 breast biopsies a year. That’s not very much experience to base a sound diagnosis on. So make sure that your pathologist has considerable experience reading breast biopsies. Also, as mentioned earlier, collect several opinions before acting on a diagnosis. And finally, remember there are alternative treatments available — and prevention through diet and lifestyle choices is always an option.