Ovarian Cancer

Overview

Cancer is a disease in which certain body cells divide quickly, producing tissue that forms a tumor. When the tumor begins to form in the cells that line the ovary or in the egg cells, it is known as ovarian cancer.

Tumors found in the ovaries may be non-cancerous tissue growths (cysts) or cancerous growths that could spread to other parts of the body. Most cases of ovarian cancer occur in women over the age of 50, but this disease can also hit younger women.

Ovarian cancer causes more deaths than any other cancer of the female reproductive system. The sooner ovarian cancer is found and treated, the better a woman's chance for recovery. However, there is no high quality screening test for ovarian cancer. With early detection and treatment, the survival rate for ovarian cancer is over 90 per cent.

Symptoms

Many times, women with ovarian cancer have no symptoms or just mild symptoms until the disease is in an advanced stage. Scientists are searching for new ways to detect ovarian cancer earlier. When symptoms do appear, they may include:

  • changes in bowel habits
  • fatigue
  • frequent need to urinate
  • gastrointestinal problems, such as gas, bloating, or constipation
  • menstrual irregularities
  • pain or swelling of the abdomen
  • pelvic pain
  • unexplained weight gain or weight loss

If you have one or more of these symptoms and they last longer than 3 weeks, see your doctor. These symptoms can also be caused by other conditions. Only your doctor can diagnose the problem.

Cause

The exact cause of cancer is unknown although inherited gene mutations are to blame for some ovarian cancers. The genes in cells carry the hereditary information that is received from the parents. Hereditary ovarian cancer makes up approximately 5% to 10% of all cases. In addition to having a family history of ovarian cancer, you are at higher risk if you:

  • are over the age of 50
  • have never had children
  • have ever used birth control pills

Diagnosis

There are different ways to diagnose ovarian cancer:

  • Pelvic exam and pap smear: A pap smear does not detect ovarian cancer but rather problems with the cervix
  • Ultrasound exam: A procedure in which high-energy sound waves (ultrasound) are bounced off internal tissues or organs to make echoes. The echoes form a picture of body tissues called a sonogram.
  • CA 125 assay: A test that measures the level of CA 125 in the blood. An increased CA 125 level is sometimes a sign of cancer or another condition.
  • Barium enema: A barium enema is inserted into the rectum and x-rays are taken of the lower gastrointestinal tract.
  • Intravenous pyelogram (IVP): A series of x-rays of the kidneys, ureters, and bladder to find out if cancer has spread to these organs. A contrast dye is injected into a vein. As the contrast dye moves through the kidneys, ureters, and bladder, x-rays are taken to see if there are any blockages.
  • CT scan (CAT scan): A procedure that takes a series of detailed pictures of areas inside the body, from different angles. The pictures are made by a computer linked to an x-ray machine. A dye may also be injected into a vein or swallowed to help the organs or tissues show up more clearly.
  • Biopsy: a tissue sample is taken from a tumor and the cells are examined under a microscope by a pathologist to check for signs of cancer.

Stages

There are different stages of cancer. Each stage reflects how much the cancer has advanced or spread:

Stage I

In stage I, cancer is found in one or both of the ovaries and has not spread. Stage I is further divided into stage IA, stage IB, and stage IC:

  • Stage IA: Cancer is found in a single ovary.
  • Stage IB: Cancer is found in both ovaries.
  • Stage IC: Cancer is found in one or both ovaries and either on the outside surface of one or both ovaries; or the outer covering of the tumor has ruptured broken open; or cancer cells are found in the fluid of the peritoneal cavity or in washings of the peritoneum (tissue lining the peritoneal cavity).

Stage II

In stage II, cancer is found in one or both ovaries and has spread into other areas of the pelvis. Stage II is divided into stage IIA, stage IIB, and stage IIC:

  • Stage IIA: Cancer has spread to the uterus and/or the fallopian tubes.
  • Stage IIB: Cancer has spread to other tissue within the pelvis.
  • Stage IIC: Cancer has spread to the uterus and/or fallopian tubes and/or other tissue within the pelvis and cancer cells are found in the fluid of the peritoneal cavity or in the tissue lining the peritoneal cavity.

Stage III

In stage III, cancer is found in one or both ovaries and has spread to other parts of the abdomen. Stage III is divided into stage IIIA, stage IIIB, and stage IIIC:

  • Stage IIIA: The tumor is found only in the pelvis, but cancer cells have spread to the surface of the peritoneum- the tissue that lines the abdominal wall and covers most of the organs in the abdomen.
  • Stage IIIB: Cancer has spread to the peritoneum but is 2 centimeters or smaller in diameter.
  • Stage IIIC: Cancer has spread to the peritoneum and is larger than 2 centimeters in diameter and/or has spread to lymph nodes in the abdomen.

*Cancer that has spread to the surface of the liver is also considered stage III disease.

Stage IV

In stage IV, cancer is found in one or both ovaries and has spread beyond the abdomen to other parts of the body.

Treatment

The type of treatment depends on the following factors:

  • the stage of the cancer
  • the type of cancer and size of the tumor
  • the patient's age and general health
  • whether the cancer has just been diagnosed or has returned

There are three types of standard treatment:

  • surgery
  • chemotherapy
  • radiation therapy

Surgery

Surgery is the most common treatment for an ovarian tumor. A doctor may take out the cancer using one of the following types of surgery:

  • Unilateral salpingo-oophorectomy: A surgical procedure to remove one ovary and one fallopian tube.

  • Total hysterectomy: A surgical procedure to remove the uterus, including the cervix. If the uterus and cervix are taken out through the vagina, the operation is called a vaginal hysterectomy. If the uterus and cervix are taken out through a large incision in the abdomen, the operation is called a total abdominal hysterectomy. If the uterus and cervix are taken out through a small incision in the abdomen using a laparoscope, the operation is called a total laparoscopic hysterectomy.

  • Bilateral salpingo-oophorectomy: A surgical procedure to remove both ovaries and both fallopian tubes.

  • Tumor debulking: A surgical procedure in which as much of the tumor as possible is removed. Some tumors may not be able to be completely removed.

Chemotherapy

Chemotherapy uses drugs to stop the growth of cancer cells, either by killing the cells or by stopping them from dividing. How chemotherapy is administered depends on the type and stage of the cancer being treated. When chemotherapy is taken by mouth or injected into a vein or muscle, the drugs enter the bloodstream and can reach cancer cells throughout the body. When chemotherapy is placed directly in the spinal column, an organ, or a body cavity such as the abdomen, the drugs mainly affect cancer cells in those areas.

Radiation therapy

Radiation therapy uses high-energy x-rays or other types of radiation to kill cancer cells. There are two types of radiation therapy.

1) External radiation therapy uses a machine outside the body to send radiation toward the cancer.

2) Internal radiation therapy uses a radioactive substance sealed in needles, seeds, wires, or catheters that are placed directly into or near the cancer.

Even if the doctor removes all the cancer that can be seen at the time of the operation, some patients may be offered chemotherapy or radiation after surgery to kill any cancer cells that are left. Treatment given after the surgery to increase the chances of a cure is called adjuvant therapy.

Following radiation or chemotherapy, an operation called a second look laparotomy is sometimes done. This is similar to the laparotomy that determines the stage of the cancer. During the second look operation, the doctor will take samples of lymph nodes and other tissues in the abdomen to see if any cancer is left.

Prevention

You are less likely to develop ovarian cancer if you:

  • use or have used oral contraceptives
  • have given birth during a normal term pregnancy
  • breast feed your children
  • have had a tubal ligation (tying the fallopian tubes)

The National Ovarian Cancer Association recommends that women have a vaginal/rectal pelvic examination every year.