Cancer begins in cells, the building blocks that make up tissues. Tissues make up the organs of the body.
Normally, cells grow and divide to form new cells as the body needs them. When cells grow old, they die, and new cells take their place.
Sometimes, this orderly process goes wrong. New cells form when the body does not need them, and old cells do not die when they should. These extra cells can form a mass of tissue called a growth or tumor.
- Benign tumors are not cancer:
- Benign tumors are rarely life-threatening.
- Generally, benign tumors can be removed. They usually do not grow back.
- Benign tumors do not invade the tissues around them.
- Cells from benign tumors do not spread to other parts of the body.
- Malignant tumors are cancer:
- Malignant tumors are generally more serious than benign tumors. They may be life-threatening.
- Malignant tumors often can be removed. But sometimes they grow back.
- Malignant tumors can invade and damage nearby tissues and organs.
- Cells from malignant tumors can spread to other parts of the body. Cancer cells spread by breaking away from the original (primary) tumor and entering the lymphatic system or bloodstream. The cells invade other organs and form new tumors that damage these organs. The spread of cancer is called metastasis.
Benign and Malignant Cysts
An ovarian cyst may be found on the surface of an ovary or inside it. A cyst contains fluid. Sometimes it contains solid tissue too. Most ovarian cysts are benign (not cancer).
Most ovarian cysts go away with time. Sometimes, a doctor will find a cyst that does not go away or that gets larger. The doctor may order tests to make sure that the cyst is not cancer.
Ovarian cancer can invade, shed, or spread to other organs:
- Invade: A malignant ovarian tumor can grow and invade organs next to the ovaries, such as the fallopian tubes and uterus.
- Shed: Cancer cells can shed (break off) from the main ovarian tumor. Shedding into the abdomen may lead to new tumors forming on the surface of nearby organs and tissues. The doctor may call these seeds or implants.
- Spread: Cancer cells can spread through the lymphatic system to lymph nodes in the pelvis, abdomen, and chest. Cancer cells may also spread through the bloodstream to organs such as the liver and lungs.
When cancer spreads from its original place to another part of the body, the new tumor has the same kind of abnormal cells and the same name as the original tumor. For example, if ovarian cancer spreads to the liver, the cancer cells in the liver are actually ovarian cancer cells. The disease is metastatic ovarian cancer, not liver cancer. For that reason, it is treated as ovarian cancer, not liver cancer. Doctors call the new tumor "distant" or metastatic disease.