A new report from the American Cancer Society provides an overview of ovarian cancer occurrence and mortality data.

Ovarian Cancer Statistics, 2018 is published early online in CA: A Cancer Journal for Clinicians.

In 2018, there will be approximately 22,240 new cases of ovarian cancer diagnosed and 14,070 ovarian cancer deaths in the United States.

In the U.S., overall ovarian cancer incidence declined by 29% from 1985 (16.6 per 100,000) to 2014 (11.8 per 100,000), while mortality declined 33% from 1976 (10.0 per 100,000) to 2015 (6.7 per 100,000).

Decreases in ovarian cancer incidence has been driven largely by declines in whites that accelerated during the past decade.

Racial/ethnic differences in ovarian cancer risk are partially explained by known risk factors.

Multiple births, use of oral contraceptives, tubal ligation, and oophorectomy reduce risk, while menopausal hormone use increases risk. However, the source of most of the variation remains unknown.

Declines in ovarian cancer mortality are due to reductions in incidence as well as improvements in treatment.

The strongest risk factor for ovarian cancer is a family history of breast or ovarian cancer.

Mutations in BRCA1 and BRCA2 account for almost 40% of ovarian cancer cases in women with a family history of the disease.

Due to a relatively high prevalence of identified genetic mutations, genetic testing is recommended for all women diagnosed with ovarian cancer to inform their medical and reproductive decisions and those of their relatives.

Incidence of ovarian cancer among women over 65 has generally declined at a continuous rate since at least 1975, likely due to uptake of oral contraceptives, which confer a substantial risk reduction and also likely contributed to the recent declines in older women.

Among women who use oral contraceptives for five to nine years total, risk is reduced by about 35%.

Currently, there is no recommended screening test for ovarian cancer, although large scale randomized clinical studies to identify effective screening modalities are ongoing.

The efficacy of screening for ovarian cancer has not been demonstrated in prospective randomized controlled trials.

Studies indicate that some women experience persistent nonspecific symptoms in the months prior to diagnosis, including back pain, abdominal distension, pelvic or abdominal pain, difficulty eating or feeling full quickly, vomiting, indigestion, altered bowel habits, or urinary urgency or frequency.

Women who experience such symptoms daily for more than a few weeks should seek prompt medical evaluation.

"Although ovarian cancer is not one of the most common cancers, it causes 5 percent of cancer deaths among US women," said Lindsey Torre, MSPH, lead author of the report. "Understanding of the disease has evolved rapidly in recent years; however, much remains to be gained in ovarian cancer research."

Source: American Cancer Society