Cervical cancer rates in older women may be higher than previously thought

Older women's rates of cervical cancer are significantly higher than previously thought, because past analyses have not adjusted for the prevalence of hysterectomy in this population, a new study found.

Researchers used self-reports of hysterectomy from the Behavioral Risk Factor Surveillance System to correct age-standardized and age-specific incidence rates of cervical cancer from the Surveillance, Epidemiology and End Results 18 registry from 2000 to 2009. Results were published by Cancer on May 12.

Removing women who have had hysterectomies from the denominator of the population at risk for cervical cancer (since removal of the cervix eliminates their risk) revealed that the rate of cervical cancer continues to increase with age after age 35-39, although at a slower rate, the study found. After correction, the highest cancer incidence rate was among 65- to 69-year-old women, with a rate of 27.4 cases per 100,000. By contrast, the highest uncorrected rate was 15.6 cases per 100,000 in women age 40 to 44 years. Correcting for hysterectomy had the greatest impact on risk among older black women, because they reported a high prevalence of hysterectomy.

Including women who have had hysterectomies when calculating cervical cancer rates results in substantial bias, the researchers concluded. Removing them from the calculation “resulted in higher age-standardized and age-specific cervical cancer incidence rates, a shift in the peak incidence to older women, and an increase in the disparity in cervical cancer incidence between black and white women in the United States,” they wrote.

The study results are subject to limitations, including the possibility of recall bias in reports of hysterectomy, but they should lead to reconsideration of current screening recommendations, which call for cessation of routine cervical cancer screening at age 65, the authors said. Screening is more difficult after menopause, they acknowledged, but patients may benefit from it.