Generally, ovarian cancer does not exhibit many early signs until the cancer grows. Women should consult their physician if they experience pressure or fullness in the pelvis, abdominal bloating, or changes in bowel and bladder patterns that continue and/or worsen.
Early detection and diagnosis remain a woman's best opportunity to treat gynecologic cancers. Routine annual gynecologic examinations are the first line of defense.
Unfortunately, few advances have occurred in the early detection of ovarian cancer, the most virulent gynecologic malignancy. Physicians still rely on physical examination, a blood test measuring levels of CA 125 and radiologic studies.
The cause of ovarian cancer is unknown, but several risk factors are associated with the disease.
- Age -- The incidence of ovarian cancer rises with age. Half of all cases are detected in women older than 65, and most are diagnosed after age 60. The American Cancer Society recommends annual pelvic exams for all women over age 40 to increase the chances of early detection.
- Genetics -- Women with a family history of ovarian cancer face an increased risk. Having one close relative with the disease increases the risk threefold, and the more relatives with the disease, the greater the risk.
Part of the increased familial risk can be explained by genetic mutations in the BRCA1 and BRCA2 genes that normally help protect against both breast and ovarian cancer. Women who inherit mutations in BRCA1 have a 50 percent risk of developing the disease, while a mutation in the BRCA2 genes results in a 20 percent risk. A mutation in another gene that normally protects against a type of colon cancer called hereditary non-polyposis colon cancer also raises the risk of ovarian cancer, but to a lesser degree than mutations in BRCA1 and BRCA2.
Families that carry mutations in these genes can come from any background, but a National Cancer Institute study found that the mutations are highest among Asheknazi Jews (whose ancestors came from Eastern and Central Europe); about 2 percent of all Asheknazi Jews carry mutations in BRCA1 or BRCA2.
Treatment begins with surgery to remove as much of the ovarian cancer as possible and to determine where it has spread. Afterward, chemotherapy will most likely be recommended to destroy any malignant cells that have escaped the surgeon's knife. Radiation therapy is not routinely used for ovarian cancer. After chemotherapy, many patients have a "second-look" operation to see if the cancer has been eradicated. If not, more chemotherapy is administered at the time of diagnosis.
The extent of surgery depends on how advanced the disease is, but it almost always involves removing the ovaries, uterus and fallopian tubes. The only exceptions apply to some rare, less aggressive types of early ovarian cancer that develop in young women who haven't had children.
In addition to the reproductive organs, surgeons may also remove the appendix and a portion of an abdominal tissue called the "omentum," where cancer cells may cluster. The liver and intestines will also be checked for signs of cancer, and biopsies of normal-looking tissue may be taken to see if cancer cells are present. The abdominal cavity is also "washed" with a saline solution to check for cancer cells. These procedures contribute to determining the extent or "stage" of the cancer. After surgery, treatment is based on the stage of the cancer.
The following staging system was established by the International Federation of Gynecology and Obstetrics to describe the progression of ovarian cancer from its earliest to most advanced stages:
- Stage I -- Cancer is limited to the ovaries. Treatment: Surgery.
- Stage IA -- Cancer is inside one ovary but hasn't reached the surface; no fluid accumulation in the abdomen; no tumor on the ovary's external surface; the capsule surrounding the ovary is intact. Treatment: Surgery.
- Stage IB -- Cancer is in both ovaries; no fluid in the abdomen; no cancer on the outer surfaces of the ovaries; the ovarian capsules are intact. Treatment: Surgery.
- Stage IC -- Cancer is on the outer surface of one or both ovaries; the ovarian capsule is ruptured; or abdominal fluid is present or cancer cells were found in the fluid used to wash the abdomen during surgery. Treatment: Surgery, chemotherapy and perhaps radiation.
- Stage II (A, B, C) -- Cancer has spread to the uterus, fallopian tubes or other parts of the pelvis; at stage IIC cancer has spread to the pelvis and the cancer is on the outer surface of one or both ovaries; the capsule has ruptured; or abdominal fluid is present or malignant cells appear in abdominal washings. Treatment: Surgery and chemotherapy.
- Stage III (A, B, C) -- Cancer is in both ovaries with spread to abdominal lymph nodes or to the outer surface of the liver, intestine or other abdominal organs; at stage IIIA microscopic deposits of cancer cells are found on the outer surfaces of abdominal organs; at stage III B cancer is limited to the pelvis, the lymph nodes are negative but cancer no larger than two centimeters is found on abdominal organs; at stage IIIC cancer affecting the abdomen is larger than two centimeters and/or some lymph nodes are positive for cancer. Treatment: Surgery, including removal of the omentum, followed by chemotherapy.
- Stage IV -- One or both ovaries are affected; cancer has spread to the inside of the liver, to other abdominal organs or to organs outside the abdomen. Treatment: The same type of surgery as for stages IIIABC, followed by chemotherapy.
Chemotherapy for ovarian cancer is typically given intravenously every three to four weeks for six to 12 months. A combination of drugs, often platinum (Cisplatin) plus paclitaxel (Taxol), is recommended because they are more effective than a single agent. These drugs work by interfering with the ability of cancer cells to reproduce. While disrupting cancer cells, they also damage healthy cells and cause a number of unpleasant side effects. Possible side effects include:
- Nausea and vomiting (these can now be controlled with Zofran (ondansetron), Kytril (granisteron) and Anzemet (dolasetron), given at the same time as the chemotherapy drugs)
- Temporary hair loss
- Increase or decrease in appetite
- Premature menopause
- Changes in the menstrual cycle
- Increased susceptibility to infection and sores in the mouth or vagina
The most serious side effect is the possibility of developing acute myeloid leukemia, a life-threatening disorder of white blood cells. This complication occurs in only a very small number of all cancer patients treated.
A variety of experimental chemotherapy regimens are being employed to increase survival in patients with advanced ovarian cancer.
Intraperitoneal chemotherapy may be recommended for women who responded well to the initial chemotherapy but who either are later found to have residual cancer cells in the abdomen or have more advanced tumors. This form of chemotherapy involves delivering the drugs directly into the abdominal cavity.
Radiation therapy is rarely used to treat ovarian cancer in the United States. When used, X-rays are aimed at the abdomen or an implant of radioactive material is inserted at the tumor site. When radiation is delivered externally, the skin over the treated area may redden as if it were sunburned, but this fades over time. Apart from this small risk, the side effects include fatigue, nausea and diarrhea.
After surgery and during chemotherapy, ovarian cancer patients may be monitored with CA125 tests. Rising levels of this protein indicate a recurrence and the need for more therapy. In addition, many doctors routinely perform "second-look" surgery after a six- or 12-month course of chemotherapy. This procedure involves opening the abdomen and taking tissue samples in a search for cancer cells. If additional cancer cells are found, chemotherapy is repeated.
"Second-look" surgery is somewhat controversial because additional cancer is often found or the cancer recurs. Opponents of a "second look" advocate continuing chemotherapy instead of subjecting patients to more surgery.