How can cancer spread through the body

But some may survive and grow to form tumours in one or more lymph nodes. This is called lymph node spread. The lymphatic drainage system! Content not working due to cookie settings.

Read a transcript of the video. Micrometastases are areas of cancer spread metastases that are too small to see. They are too small to show up on any type of scan. For a few types of cancer, blood tests can detect certain proteins that the cancer cells release.

These are sometimes called tumour markers. These may show that there are metastases in the body that are too small to show up on a scan. But for most cancers, there is no blood test that can say whether a cancer has spread or not. For most cancers, doctors can only say whether it is likely or not that a cancer has spread.

Doctors base this on a number of factors:. This information is important in treating cancer. You might have extra treatment if doctors suspect there are micrometastases. This treatment might include:. Cancer, the blood and circulation. Sometimes the metastatic tumors have already begun to grow when the cancer is first found. And sometimes, a metastasis may be found before the original primary tumor is found.

Where a cancer starts is linked to where it will spread. This video shows how a type of skin cancer called melanoma can metastasize. Although the appearance of cancer cells and the way they spread varies depending on the type of cancer, the general concepts shown here are useful in understanding how any cancer can spread. Keep in mind that not all cancers metastasize. Melanoma begins in the melanocytes — cells that produce skin color, or pigment. Melanoma typically begins as a mole.

If you catch the melanoma early and it hasn't spread, it can be surgically treated. Here you see a superficial melanoma being removed, along with the surrounding skin. The extra skin is taken to ensure that no cancer cells are left behind. Melanoma is dangerous because it can spread beyond what you can see, moving deep into your skin where it can gain access to your lymphatic vessels.

This allows cancer cells to travel to distant locations in your body. Cancer cells can also travel to different parts of your body by way of your blood vessels. In many cases, treatment will consist of more than one therapy. Depending on the type of cancer you have, surgery may be the first-line treatment. When surgery is used to remove a tumor, the surgeon also removes a small margin of tissue around the tumor to lower the chances of leaving cancer cells behind.

Surgery can also help stage the cancer. For example, checking the lymph nodes near the primary tumor can determine if cancer has spread locally. You may also need chemotherapy or radiation therapy following surgery. This may be an added precaution in case any cancer cells were left behind or have reached the blood or lymph system.

This can be helpful if the tumor was causing pressure on an organ or causing pain. Radiation uses high-energy rays to kill cancer cells or slow their growth. The rays target a specific area of the body where cancer has been found. Radiation can be used to destroy a tumor or to relieve pain. It can also be used after surgery to target any cancer cells that may have been left behind. Chemotherapy is a systemic treatment.

Chemo drugs enter your bloodstream and travel throughout your body to find and destroy rapidly dividing cells. Chemotherapy is used to kill cancer, slow its growth, and reduce the chance that new tumors will form. Targeted therapies depend on the specific type of cancer, but not all cancers have targeted therapies. These drugs attack specific proteins that allow tumors to grow and spread. Angiogenesis inhibitors interfere with the signals that allow tumors to form new blood vessels and continue growing.

These medicines can also cause already existing blood vessels to die, which can shrink the tumor. Some types of cancer, like prostate and most breast cancers , need hormones to grow.

Hormone therapy can stop your body from producing the hormones that feed the cancer. Others stop those hormones from interacting with cancer cells.