Ovarian cancer is remains relatively rare in the United States, but it continues to be one of the most deadly cancers.
Although it accounts for only about 3 percent of cancers in women, it causes more deaths than any other cancer of the female reproductive system, the American Cancer Society reports.
This year, more than 22,000 women will be diagnosed with ovarian cancer and more than 14,000 will die from the disease.
Although that number pales in contrast to the 40,000 breast cancer deaths, the mortality rate for ovarian cancer patients is about five times the rate for those diagnosed with breast cancer.
Doctors say early diagnosis of ovarian cancer is difficult because there is no reliable early screening test.
“The problem is it is notoriously hard to detect until it’s in its later stages,” said Dr. Joseph Meyn, an obstetrician/gynecologist at Indiana Regional Medical Center.
Some had hoped a blood test measuring the level of a protein associated with ovarian cancer may be used as a screening tool, but research has not shown that it works. The test, known as CA-125 for measuring cancer antigen 125, can be used to monitor the cancer’s progress.
“CA-125 is not a screening test,” Dr. Lindsay Mastrine, gynecologist, said at Chan Soon-Shiong Medical Center at Windber. “It just hasn’t proven to be reliable.”
Elevated levels of CA-125 can also be associated with lower bowel conditions and Crone’s disease, Meyn said.
Education and an annual gynecological exam provide the best defense, Mastrine said.
“They should keep their appointments with their gynecologists,” Mastrine said. “And they should be aware and look for signs and symptoms – and don’t ignore those things.”
Early signs include pain in the pelvic or abdominal area, back pain, feeling full quickly when eating, bloating and unusual vaginal discharge or bleeding.
The symptoms are so non-specific that women often don’t follow up with their doctor until the malignancy has spread into other organs, Meyn said.
A gynecologist can sometimes find tumors during a pelvic exam, and an ultrasound imaging test can identify suspicious cysts. But a definite diagnosis comes from the lab.
“Ultimately, the way you diagnose ovarian cancer is surgically,” Meyn said. “You have to go in and get the tissue out. In our office, we do a lot of resections of cysts. Thank God the vast majority are benign.”
Meyn said more malignancies are being identified early, when they are labeled as “borderline.”
“For them, treatment is just taking the ovary out, alone,” Meyn said. “Those women are very fortunate.”
Many people are aware that a family history of breast or ovarian cancer may increase a woman’s risk of getting ovarian cancer, but Meyn warns that heredity is not the main indicator. Most cancer occurs spontaneously.
“The biggest risk factor for all cancers, regardless of the location of the cancer, is age,” Meyn said.
He predicts there will be more cancer diagnoses in the coming years.
“We are living longer and longer,” he said. “As you get older you are going to find stuff. We haven’t seen a lot of carcinoma yet, but it’s coming. You can sense that we are going to see more cases in the future.”
Some women mistakenly believe an annual Papanicolaou test, or Pap test, can show ovarian cancer.
“The Pap test is a test for cervical cancer,” Mastrine said.
Scientists continue to look for markers, usually proteins, in the blood that will serve as a reliable early warning for ovarian cancer. Meyn says the success of the Pap test demonstrates the impact of reliable screening.
“Cervical cancer is so rare in this country because we do Pap tests,” he said. “If you go to third world countries, where there are no routine pap tests, cervical cancer is their No. 1 gynecological killer. It way outstrips breast, ovarian and endometrial cancers combined.”
He recommends Pap tests and annual mammograms for all women who meet screening guidelines.
“If you don’t get the screenings you relegate yourself to the medical care of a third world country,” he said.