Understanding Cancer Recurrence
An overview of advanced cancer and living with metastatic disease
No matter your diagnosis or treatment status, every person who has been diagnosed with cancer has a common concern: what if my cancer comes back? It's a large and complicated topic, due to the wide variety of ways cancer works in the body, as well as the unpredictability of the disease.
We spoke with Anne Schott, M.D., associate professor of medical oncology at the University of Michigan Rogel Cancer Center, who specializes in breast cancer, to cover some of the basic questions patients ask about their cancer, the possibility of its return and what it means when cancer is metastatic.
Q. What do we mean when we say a person’s cancer is recurrent?
A cancer recurrence means that a person who was thought to be cancer free has cancer again. This can be interpreted in several ways.
If the cancer returns to the same primary location, it is called a local recurrence. If the cancer is detected in surrounding lymph nodes to the original location, it is a regional recurrence. If the cancer has spread to distant parts of the body, it is called metastatic recurrence. Metastatic cancer is also called stage 4.
Cancer recurrence is treated differently depending on the specific type of cancer and the location of the recurrence.
Q. What are some of the common misconceptions patients have about the spread of cancer?
One of the biggest sources of confusion for patients comes when their cancer has spread from one location to another. For example, it is possible for breast cancer to spread to the bone. People will assume they now have bone cancer, but this is not the case. They actually have metastatic breast cancer.
Cancer is treated by cell type. Breast cancer cells respond in certain ways to certain treatments. If cancer has spread to the bone, you will still receive treatment for breast cancer.
Q. What does it mean when you have metastatic cancer?
Cancer that has spread outside of the primary site and nearby lymph nodes is metastatic. With a few exceptions, we call it stage 4. Advances in treatment allow us to manage cancer symptoms and shrink cancerous tumors, but metastatic cancer is rarely curable.
The goal for treating a spread cancer is to reduce tumor size and relieve some of the symptoms that patients experience. This allows us to prolong an individual's life and, in many cases, allows a person to live a high-quality life.
Q. How does cancer spread?
Cancer, by its very nature, is designed to spread. Cancer develops when your body's cells go awry and begin reproducing and invading surrounding tissue in a way that nature did not intend. The cancer cells travel to different parts of the body and begin forming new tumors.
How cancer spreads varies depending on the type of cancer you have, but generally it spreads through the bloodstream or the lymph system. A point of confusion for patients is that cancer only spreads if it has already gotten to the lymph nodes. However, we know this isn’t the case. An example is breast cancer that has spread to the brain. The only way this can occur is through the bloodstream.
Why cancer spreads to specific areas of the body is being researched. We believe there are signals that make certain cancers go to certain areas of the body. Perhaps we can disrupt those homing signals with future treatment to prevent metastasis.
Q. How do doctors know where a cancer has spread?
Cancer researchers have learned over time that different cancers have a tendency to spread to certain parts of the body. For example, it is most common for breast cancer to spread to the lymph nodes and bones. It can also spread to the liver, lungs or brain.
Patients will often ask: How do you know my breast cancer has spread to the brain? How do you know I don’t have brain cancer instead? The answer is that primary brain cancer looks very different under a microscope than metastatic breast cancer that is in the brain.
A patient's prior cancer is always taken into account if cancer appears again. It is far more common for a cancer the patient already had to spread than it is for a patient to have a second primary diagnosis. It happens, but much less frequently.
Q. How is treatment evolving when it comes to metastatic cancer?
It is very important to know the origin and specific type of a person's cancer because this information guides treatment options. The first time a cancer spread is detected, we get a biopsy to confirm the type of cancer whenever possible. This is very important because even a single cancer type like breast cancer has many subtypes, and each is managed a little differently.
We’re starting to understand that as stage 4 cancers are treated, cancer may start to behave differently over time. The reason that many metastatic cancers are not cured is because, although the cancers respond to initial therapy, they eventually become resistant. Later biopsies help us understand what is driving the resistance and give us clues on how to treat it.
Q. How long do patients wait before they know if their cancer will return?
I wish there were an easy answer, but the timeframe varies depending on the cancer and the cancer subtype. Some cancers are considered cured if they don’t come back in five years. In small cell lung cancer, if it hasn't recurred in three years it is not likely to recur. But certain hormone-sensitive breast cancers can show up 20 years later as a spread cancer.
It is very specific to the kind of cancer you have, so be sure to ask your doctor.
Continue learning about cancer recurrence
Read Thrive, Summer, 2014