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What is Cancer - Types, Stages, Cancer Diagnosis

What Is Cancer?

To understand any cancer type, it’s first important to understand what cancer is: basically, the production of abnormal cells.

The body is programmed to routinely replenish cells in different organs. As normal cells age or get damaged, they die off. New cells take their place. This is what’s supposed to happen. Abnormal cell growth refers to a buildup of extra cells. This happens when:

  • new cells form even though the body doesn’t need them or
  • old, damaged cells don’t die off.

These extra cells slowly accumulate to form a tissue mass, lump, or growth called a tumor. These abnormal cells can destroy normal body tissue and spread through the bloodstream and lymphatic system.

There are 4 main types of cancer:

  • Carcinoma: This cancer starts in skin or in tissues that cover your internal organs.
  • Sarcoma: This cancer starts in your muscle, fat, bones, cartilage, blood vessels, connective tissue or supportive tissue.
  • Leukemia: Starts in blood-forming tissue like bone marrow. In this type of cancer, a large number of abnormal blood cells are made and travel into your bloodstream.
  • Lymphoma and multiple myeloma: Starts in cells of your immune system.

Cancer is usually named by the site it began. This site is called the primary. For example, breast cancer is called breast cancer because the cancer cells began in the breast.

A tumor or lump does not automatically mean cancer. Some tumors are benign.

Benign vs. Malignant: What’s the Difference?

Benign means not cancerous. A benign tumor can get larger but does not spread to other tissues or organs.

Malignant means cancerous. A malignant tumor’s cells can invade nearby tissue and lymph nodes and then spread to other organs. These cells are destructive.

  • Benign Tumors:
    • Can be removed
    • Usually don’t grow back
    • Are rarely fatal
    • Don’t spread to other tissues or body parts
  • Malignant tumors:
    • Can often be removed
    • Sometimes grow back
    • Can invade other tissues and organs and cause damage
    • Can spread to other body parts
    • Can be fatal

How is Cancer Diagnosed?

What Are the Stages of Cancer?

Finding an Oncologist