In order to understand how your doctor decides which treatment(TREET-MINT) — Techniques to help eliminate or control a disease is best for you, you need to learn several key concepts about how cancer grows and spreads.

Think about the weeds in your garden. If you leave them unattended, they can take over the entire flowerbed and yard.

Interestingly enough, it begins quite simply. It all starts with a single dandelion in a single flowerbed. As soon as you see this first dandelion, you have to decide if it should be removed. It’s important to take action immediately because weeds spread very easily and become a huge problem. Removing the original dandelion will prevent its roots from branching out and invading the soil. If you are lucky enough to only have a single dandelion in your flowerbed that has not spread, the problem can typically be resolved by plucking it.

There is a similar pattern between the growth of dandelions and the growth of cancer in your body.

If only a single spot of cancer is discovered and there is no evidence of spreading from the original location, doctors will describe the cancer as local disease(LOW-COAL DUH-ZEEZ) — Cancer that remains near the original cancer that can usually be removed with one surgical procedure. It is still considered local disease even if it is invasive(IN-VAY-ZIV) — Something that penetrates or enters, like the roots of the dandelion in soil. What makes a cancer local disease is that the cancer can be removed easily with one procedure.

But not all cases are this easy. If the cancer is not detected and removed early, it can spread from its original location. If the cancer is more advanced, then doctors have two big categories to summarize the type of spread: local spread(LOW-COAL SPRED) — Disease that has only spread to areas near the original cancer and systemic spread(SIS-TEM-IK SPRED) — Disease that has spread throughout the body through the bloodstream.

Local spread is when cancer has spread to places close to the original tumor(TOO-MER) — Abnormal growth in the body. This is like finding multiple dandelions in the same flowerbed or flowerbeds nearby. Systemic spread is when cancer has spread to places beyond the original location to other organs in the body. This is like finding dandelions far from the original flowerbed throughout the yard.

Defining how far the cancer has spread (the extent of the diseaseHow far the disease has spread) is a very important factor in determining the best treatment options. Your doctor will use the extent of your disease and other characteristics of the cancer to make treatment recommendations.