Ovarian Cancer Mortality Declining in United States, Europe

Ovarian cancer mortality rates declined significantly in several parts of the world from 2002 to 2012, according to a new study. Among the main reasons for the decline is the use of oral contraceptives, particular in the United States and European Union.

Previous work has shown a leveling off and subsequent decrease of ovarian cancer mortality rates in high-income countries such as the United States and parts of the European Union, where rates were highest. “These are countries where oral contraceptives-which have a long-term protective effect on ovarian cancer risk-were introduced earlier and used more frequently,” wrote study authors led by Eva Negri, PhD, of the Istituto di Ricerche Farmacologiche Mario Negri in Milan. “However, persisting marked differences in ovarian cancer patterns and trends across various areas of the world remain.”

The new study examined death certification data for ovarian cancer from the World Health Organization database, from 1970 to 2012 (or nearest available year). The results were published online ahead of print on September 5 in Annals of Oncology.

In the European Union, the age-standardized mortality rate dropped by 9.9% from 2002 to 2012, from 5.76 per 100,000 women to 5.19 per 100,000 women. The biggest decline was seen in the youngest group, aged 20 to 49 years. In the United States, there was an even larger decline in mortality, from 5.76 per 100,000 women to 4.85 per 100,000 women (15.8% decline).

Japan saw a more modest decline of 2.1% from 2002 to 2012, while Australia (11.8% decline) and New Zealand (12.1% decline) were more similar to the European Union and United States.

There were some countries that saw increases in ovarian cancer mortality; for example, the Republic of Korea’s rate rose by 6.1%, though its baseline was low, at 2.13 per 100,000 women up to 2.26 per 100,000 women. Other countries in Latin America, such as Colombia (9.7% increase), Cuba (8.9% increase), and Venezuela (5.6% increase) also saw low rates rise slightly. In the European Union, only Bulgaria had an increase, of 27.7%.

The study also conducted an analysis to predict ovarian cancer mortality rates out to 2020 in eight countries. All countries modeled except for Spain (which began with the lowest rate) showed a favorable trend, with an approximately 15% decline expected in the United States. In the Japan, the decline is expected to be 10%, similar to that across the European Union.

Along with long-term oral contraceptive use, the authors wrote that a recent decrease in menopause hormone use likely also contributes to the decline in ovarian cancer mortality particularly in elderly women. “Delays in the adoption of recent advancements in diagnosis and management may have unfavorably affected mortality in central and eastern European countries,” they noted, adding that obesity, diet, and other environmental factors have also been linked to ovarian cancer risk. “The quantification of their effect on national mortality rates remains undefined.”