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When cancer spreads

If only cancer would stay put. Unfortunately, cancer cells grow rapidly and erratically and can travel to distant body areas. When cancer takes hold in a new location, this spread of disease is called metastasis. Fatal cancers usually involve metastatic tumors that affect a critical organ or spread to several locations. But metastatic cancer isn’t necessarily untreatable. Here are answers to some frequently asked questions about metastatic cancer:

How does cancer spread?

When cells break away from a cancerous tumor, they can move through the bloodstream or lymph vessels to other parts of the body. While most of these traveling cells die, the most malignant ones can settle in other organs or body areas.

What’s the difference between primary and metastatic tumors?

The original cancer site is referred to as the primary tumor. Tumors that form elsewhere are called metastatic. For example, when breast cancer cells spread to a lung, the cancer is called metastatic breast cancer, not lung cancer. When cancer is found anywhere in the body, doctors will conduct blood tests, X-rays, MRI scans and other exams to determine whether the cancer appears elsewhere.

Can all cancers metastasize?

Cancer can begin in any body organ or tissue and these cells can travel and spread to almost any other part. Cancer that travels only a short distance, such as when breast cancer cells spread to nearby underarm lymph nodes, is called regional disease. But breast cancer cells found in the groin area’s lymph nodes are considered metastatic.

Where do metastatic tumors occur?

When cancer spreads, it most commonly settles in the lungs, bones, liver and brain. Many cancers spread to the lungs because blood containing the cancerous cells is pumped through the lungs before circulating elsewhere. Likewise, stomach and colon cancers often travel to the liver via normal blood flow from the intestines. Prostate cancer tends to spread to bones.

In other cases, experts believe genetic cell changes allow some cancers to spread. And some cancer cells are believed to have a surface substance that helps them “stick” to certain organs.

Are there treatments for metastatic cancer?

Yes. Treatments are available for all stages of cancer. Treatments for metastatic cancer typically involve chemotherapy or biological therapies that circulate throughout the body and attack tumor cells wherever they are located. Other therapies, including surgery or radiation, can also be used in specific circumstances. Contrary to what many people might expect, because of improvements in current cancer therapies and in new medications to help relieve side effects, a variety of recent studies carried out in patients with metastatic cancer have shown that not only survival, but also quality of life, are significantly better when patients with metastatic cancer choose chemotherapy, in addition to medications to relieve pain and other symptoms.