Dr. Susan Love Research Foundation | My pathology report shows that I have "atypia." What does that mean?

In order for the cells removed during a biopsy to be examined, they are put on a slide, stained, and then looked at under a microscope. Cells are judged based on a number of criteria, including the size and color of the nucleus (the center of the cell that contains DNA), the appearance of the other structures in the cytoplasm (the area between the nucleus and the outer wall of the cell), and the overall size of the cell itself.

For centuries, pathologists (physicians who identify diseases by studying cells and tissues under a microscope) have been trying to predict how cells will behave based on how they appear. We know that cancer occurs when a cell becomes damaged. But this damage does not occur in one step. Instead, it takes a series of "mistakes" for a cell to be transformed from a normal cell into a cancer cell, which has the ability to grow uncontrollably and to live outside the organ where it started.

Because our bodies make hundreds of millions of new cells every second, there are billions of opportunities each day for mistakes to occur in the genetic code inside a cell's DNA. Most of the time our bodies are able to find and repair or destroy these mistakes, but not always. Some mistakes slip by. And when the cells that carry a genetic mistake reproduce, they are more prone to make more genetic mistakes. These mistakes in the genetic code inside the DNA can be reflected in the appearance of the cell, making it look abnormal.

What the precise problem is, though, is impossible to say. Sometimes cells that look bizarre do behave in a bizarre fashion. But other times cells that look very bizarre still behave fairly normally. It all depends on which genes are damaged when the cell reproduces and the microenvironment that the cells live in. Further, when looking at a cell on a slide a pathologist has no way of knowing if that cell was about to be repaired or if it was going to go undetected. The pathologist also can't determine how many mistakes have occurred within the genes and thus how close the cell might be to becoming cancerous. All the pathologist can say for sure is that the cell looks abnormal and that some damage has taken place.

The problem with the current method pathologists use to examine cells is that it is very subjective. The pathologist must determine how far from normal a cell looks, yet there is a wide variation in what is considered to be normal. This is why the experience of the pathologist reading the slides is so important and why it can be helpful to get a second opinion from another pathologist. It is hoped that in the near future pathologists will be able to analyze the genetic composition of the nucleus directly to determine how damaged a cell is. This will provide better information than that obtained by judging a cell's damage by how it looks.

In sum, as pathologists have learned more about cells and how they change, it has become clear that what matters most is how far from normal a cell looks because the less normal the cell is in appearance, the greater the chance that genetic damage has occurred. And when genetic damage has occurred, a cell has the potential to become cancerous. This does not mean that a damaged cell will turn into a cancerous cell; it means it might. This drawing illustrates the potential progression from hyperplasia and/or atypia to invasive cancer.

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Hyperplasia is the first type of abnormality in appearance. If you receive a diagnosis of hyperplasia it means that there are more cells than you would expect to see in the walls of the ducts and lobules, but that all of these cells appear normal. A diagnosis of hyperplasia does not put you at any increased risk for developing breast cancer.

Atypia means that the cells look different from normal cells. You can have atypia with hyperplasia, which means that the cells look different from normal and that there are more cells than you would expect to see. You can also have atypia without having hyperplasia. Atypia does not always progress to precancer (ductal carcinoma in situ [DCIS]) or cancer. In fact, it is not uncommon for a repeat biopsy in the same area of the breast to show entirely normal-appearing cells. Atypia can be described in a number of ways.

For example: Marked nuclear atypia: This is another way of saying that the center or the nucleus of the cells looks atypical. Focal atypia: This indicates that only a very small area of the total slides inspected was involved. Sometimes pathologists use this term as a way of hedging what is in fact a fairly subjective judgment, especially if the pathologist is not a specialist in breast pathology. It almost always means that the pathologist believes that this area is not very important overall. It's also important to keep in mind that since the pathologist is looking at these cells under the microscope they are, by definition, outside of your body and can no longer pass on any damage or become more damaged themselves. Atypical ductal hyperplasia: This means that there are extra cells present in the walls of the breast duct and that these cells look somewhat abnormal.

Atypical lobular hyperplasia: This means that there are extra cells present in the lobules (the parts of the breast that are capable of making milk) and that these cells look somewhat abnormal. A diagnosis of atypia DOES NOT mean that you have cancer or even precancer. It means that you might have a pre-precancer. In fact, most women with atypia never get breast cancer. Rather, a diagnosis of atypia means that you have a "marker" of being at increased risk for developing cancer. The increased risk for a group of women with atypia is 1 percent higher than it is for a group of women who do not have atypia. If a woman does not develop breast cancer in 10 years after being diagnosed with atypia, then her risk drops off significantly.

If the atypia was found after you underwent a core biopsy, your doctor will recommend that you have an excisional biopsy. This is done to evaluate the surrounding tissue to make sure that the core did not miss an area that could be cancer. This test will not cause any cancer that might be present to spread further into the bloodstream. Just as you would get a second opinion from another oncologist, you should get a second opinion from another pathologist. Invasive cancer and benign tissue are both relatively easy to diagnose, but when you are in the atypical hyperplasia to DCIS range there are often very fine distinctions in the degree of hyperplasia and/or degree of atypia, which makes a second opinion a very good idea.