The most important person on your medical team is someone you will probably never meet--your pathologist. The pathologist tells your surgeon and oncologist if you have cancer. The pathology report includes information about the tumor's size, its hormone and HER2 status, and its other characteristics. Your surgeon and oncologist will base many of their treatment decisions on what the pathologist tells them. So your life depends on the accuracy of the pathology report. How do you know if it is correct? Do you need to ask for second opinion on a biopsy?
A group of researchers wanted answers to this question. They wondered how often pathologists in local hospitals are accurate in their reports on breast biopsies. They published their findings in an article in The New England Journal of Medicine. The researchers asked a panel of three experts to read slides from breast biopsies. Then they sent those same slides to 110 pathologists in 8 states to see how often they agreed with the experts.
I always imagined that cancer cells would be easy to see in a biopsy slide, but the truth is that cell abnormalities fall into a range. It's not like telling the difference between bright red, blue and yellow on a color chart. Sometimes it's more a matter of distinguishing between shades. It's easy to say if your friend has black or platinum-blonde hair, but the difference between light brown and dark blonde is trickier.
Cells might be invasive breast cancer that has spread beyond the milk ducts. They might be cancer cells that haven't spread (DCIS) and may never be dangerous. They might be abnormal cells (atypia) that indicate a woman is at risk for developing breast cancer at a later date. Within a single slide, there will also be normal cells of various types. Pathologists often see cells that are difficult to classify.
In this study the local pathologists agreed with the experts 96% of the time when the slide showed invasive breast cancer. Benign tumors were correctly identified with 87% accuracy, but 13% of the time the pathologists identified benign findings as something more serious. For ductal carcinoma in situ (DCIS) the pathologists were correct 84% of the time, but 3% of the slides were incorrectly considered invasive cancer and 13% of the time they were reported as less serious. A group of slides that showed atypia (also called atypical hyperplasia) had the largest divergence between the experts' reading and the local pathologists'. Here the pathologists were only 48% correct. In 17% of the slides they reported the problem as more serious, which could lead to a woman being treated more aggressively than necessary, and 35% of the time they missed the problem, which could lead to a false sense of security.
The study found that the slides were more likely to be incorrectly read if the woman had dense breast tissue or if the pathologists worked in smaller practices where they read fewer breast biopsies per week. Should you be alarmed if you have dense breasts and your hospital doesn't do very many breast biopsies? Not necessarily. This study put up some barriers that your pathologist doesn't have. For each case, the pathologists saw only one slide and knew only the age of the woman and type of biopsy. They weren't allowed to confer with anyone else. In real life, the pathologist would have many more slides to examine and would be talking to the surgeon and other pathologists, especially if the cells were borderline in any way. So should you ask for a second opinion on a biopsy report? Here are some circumstances when it might be a good idea.
The report uses terminology like "borderline" or "inconclusive." These kinds of words in a report indicate that making a correct diagnosis is not straightforward. Having an expert at a comprehensive cancer center or research hospital read your slides might be a good idea.
You are getting a second opinion at any point in your treatment. Often the doctors with whom you consult will ask to view your original slides, but if they don't, request that they take a look. The recommendations of your second-opinion doctor won't mean much if they are based on an inaccurate report.
You are being evaluated for a rare condition. The pathologists in the study who were most accurate had the most practice. Your pathologist will have less practice with rare types of breast cancers like Paget's Disease and inflammatory breast cancer (IBC). I will always be grateful that the pathologists at my local hospital recognized that they weren't sure about my slides and sent them to a pathologist nationally recognized for his expertise in IBC. My IBC was correctly diagnosed because they asked for a second opinion.
You are uncomfortable with the treatment recommendations your doctor makes, especially if the report says you have atypia or atypical hyperplasia. If your doctors want you to have more aggressive treatment than seems warranted, or if you feel that your doctors are downplaying your concerns for frequent monitoring or follow-ups, ask for a second opinion on the pathology report. The slides with the atypical cells were the ones most frequently misread in this study, and it's important to get the diagnosis right. Doctors know a lot, but women also can have accurate gut feelings about their bodies. If something in the report doesn't sound credible to you based on what you are experiencing, ask for a second opinion.
Your treatment isn't working or you have a recurrence. Your pathology report also includes the hormone receptor and HER2 status of the tumor, and these can be even more complicated to get right than the type of cell abnormalities covered in this most recent study. The medications your doctor uses are based on these characteristics. When treatment isn't going well, another look can be a good idea. Maybe you need a hormonal treatment or targeted therapy.
A second opinion on a pathology report doesn't require another biopsy. Your slides will be sent to a different pathologist for review. Then you and your doctor can proceed with treatment plans confident that you are acting on accurate information.
For Further Reading:
Diagnosed with DCIS? Here's What You Need to Know Right Now
Invasive/Infiltrating Ductal Carcinoma (IDC)
Reading The Pathology Report - A Layperson's Guide To Understanding Your Breast Cancer Diagnosis