Risk Factors & Symptoms
Generally, ovarian cancer does not cause 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.
Although aggressive new therapies are being evaluated by Gynecologic cancer specialists at the Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, early detection and diagnosis remain a woman’s best opportunity to treat gynecologic cancers. Routine annual gynecologic examinations are the first line of defense.
Our physicians offer valuable advantages in the diagnosis of gynecologic cancers. Because it is difficult to distinguish between some types of cancerous and benign cells on biopsies, our gynecologists created a special division headed by a gynecologist who is board certified in both obstetrics/gynecology and pathology (the study of tissue and cells). The field of gynecologic pathology was pioneered at Hopkins, where specialized pathologists examine all gynecologic cancer tissue samples.
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. Cancer Center gynecologic pathologists were some of the first to discover that some ovarian tumors are not cancerous or precursors of cancer. These tumors, known as “low malignancy potential,” can often be removed by skilled Gynecologic cancer surgeons without destroying a patient’s fertility. This finding has been particularly significant for women who have not completed their childbearing.
Ovarian cancer is NOT a silent disease
Goff and coworkers from the University of Washington reported results in JAMA of a prospective case-control study of 128 women undergoing surgery for a pelvic mass and 1,709 women who visited 2 primary care clinics and completed an anonymous survey on the severity of their symptoms between July 2001 and January 2002 (Journal citation: Frequency of symptoms of ovarian cancer in women presenting to primary care clinics. Goff BA, Mandel LS, Melancon CH, Muntz HG. JAMA. 2004 Jun; 291: 2705-2712 [Abstract]). The objective of the study was to compare the frequency, severity, and duration of symptoms between women with ovarian cancer and women presenting to primary care clinics. The primary outcome measure was differences in self-reported symptoms between these groups of women. Compared to control patients (those women attending primary care clinics), ovarian cancer patients were 7.4 times more likely to report increased abdominal size, 3.6 times more likely to complain of bloating, 2.5 times more likely to have urinary urgency, and 2.2 times more likely to have pelvic pain. All of these differences were statistically significant. In addition, these investigators found that the combination of bloating, increased abdominal size, and urinary symptoms was found in 43% of women with ovarian cancer but only 8% of women presenting to primary care clinics.
This is an important study in several respects. The investigators have expanded on their previous work demonstrating that 95% of women with ovarian cancer experience some symptoms prior to diagnosis (Goff et al Cancer 2000; 898: 2068-2075), dispelling the myth that ovarian cancer is a silent disease. The results of the current study indicate that women with ovarian pathology are more likely to experience a specific constellation of symptoms that are more severe and frequent than their counterparts presenting to primary care clinics. Women presenting with non-specific symptoms, particularly if severe intensity or rapid onset, should be thoroughly evaluated for the possibility that the symptoms are due to an ovarian mass.
Ovarian Cancer Risk Factors
The cause of ovarian cancer is unknown, but several risk factors are associated with the disease.
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.
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, which 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 nonpolyposis 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.
Read more about Genetic Testing and Risk Assessment.
The incidence of ovarian cancer is highest among white women in Europe and North America and lowest among black women regardless of their location. Incidence is also low among Asian women, but this is probably due in part to environmental factors because their rate rises when they move to Western countries and adopt the lifestyles and diets of their new location.
Population studies show that ovarian cancer rates are highest in affluent societies where diets tend to be high in fat. Animal fats (the kind found in red meats, whole milk or cheese) appear to be most closely linked to ovarian cancer.
Risks are greater for women who have no or few children or have delayed childbearing until after age 35. Ovarian cancer is also more common in women who begin menstruating before age 12 or reach menopause after age 50.
It is hypothesized that the longer a woman is exposed to estrogen, the higher her risk of ovarian cancer. Since high levels of estrogen are present only during the childbearing years, the longer the woman menstruates, the higher her risk.
Childbearing may reduce risk by providing nine-month “rests” from ovulation during pregnancy, thereby reducing a woman’s overall exposure to estrogen.
The drugs clomiphene citrate and pergonal, which are commonly used to treat infertility, also appear to increase the risk of ovarian cancer when used for more than three cycles.
Birth control pills
Women who take birth control pills are at lower risk for ovarian cancer, perhaps because the pill suppresses ovulation and reduces exposure to estrogen. The longer a woman is on the pill, the lower the risk.
Talcum powder and asbestos
Habitual use of talcum powder on the genital area may increase the risk for ovarian cancer, but the evidence is not strong. A study at Harvard Medical School found that using talc this way doubled the risk, but other studies found no increased risk. Some researchers believe that talc may be carcinogenic because it contains particles of asbestos, a known carcinogen. It’s been shown that rates of ovarian cancer are higher than normal in women whose jobs expose them to asbestos.
Women with a history of breast or endometrial cancer have an increased risk of developing ovarian cancer. This association may be due to genetic mutations or to such factors as diet and estrogen exposure, which also increase the risks for these other types of cancer.