Cervical Cancer Screening In Older Age Lowered Cancer Risk

Cervical cancer screening through age 69 found to lower odds of diagnosis later in life

(RxWiki News) Adult women are recommended to get regular screenings for cervical cancer, but there is not much agreement about the age at which cervical screening should stop. Evidence about the impact of screening on cervical cancer incidence in older women is lacking.

A recent study found that continuous screening for cervical cancer at regular intervals in women's 50s and 60s significantly lowered the risk of being diagnosed with cervical cancer during their senior years compared to not getting screened.

The researchers suggested that continuing screening into old age may be necessary and beneficial as the population ages overall.

"Discuss cervical cancer screening with your doctor."

The lead author of this study was Peter Sasieni, PhD, MS, from the Centre for Cancer Prevention in the Wolfson Institute of Preventive Medicine of the Barts and The London School of Medicine and Dentistry at Queen Mary University of London in London, United Kingdom.

This study included 1,341 women with invasive cervical cancer from England and Wales in the United Kingdom.

All participants were diagnosed between January 1, 2007 and March 31, 2012, and were between the ages of 65 and 83 years old at diagnosis.

There were also 2,646 controls who were matched by age and place of residence.

Every cervical cancer case was matched with two controls except in the case of 36 women.

The researchers looked at the cervical screening histories of all the women and divided the women into four categories:

  • Adequate negative screening — a woman had at least three tests between the ages of 50 and 64 years old, with at least one test occurring from ages 60 to 64, and the last three tests were negative.
  • Sub-optimal but negative screening — a woman did not have any tests after the age of 60 but had a) at least one negative test and no abnormal tests or b) three consecutive negative tests.
  • Abnormal screening — a woman tested positive for high-grade squamous intraepithelial lesions (abnormal growth on the outer part of the cervix) between ages 50 and 64 years old regardless if the positive test was followed by three negative tests.
  • No screening — a woman did not have any tests between ages 50 and 64 years old.

The findings showed that women with adequate negative screening were at the lowest risk for cervical cancer at the age of 65 years old or older, and were 84 percent less likely to be diagnosed with cervical cancer at the age of 65 years old or older compared to the no screening group.

The participants in the abnormal screening group were found to be at the highest risk, and were 83 percent more likely to be diagnosed with cervical cancer at the age of 65 years old or older compared to the no screening group.

The researchers also found that 40 percent of the cervical cancer patients had not received screening, compared to only 16 percent of the control group. Only 21 percent of the cervical cancer patients had adequate negative screening versus 53 percent of the control group.

The findings also revealed that the risk of developing cervical cancer among the adequate negative screening group increased with age.

The researchers found that, compared to participants of the same age in the no screening group, the participants in the adequate negative screening group who were

  • Between the ages of 65 and 69 years old were 93 percent less likely to have been diagnosed with cervical cancer.
  • Between the ages of 75 and 79 years old were 72 percent less likely to have been diagnosed with cervical cancer.
  • Between the ages of 80 and 83 years old were 63 percent less likely to have been diagnosed with cervical cancer.

The researchers concluded that having adequate screening between the ages of 50 and 64 years old significantly reduced the chances of being diagnosed with cervical cancer after the age of 65 years old.

"Screening up to age 65 years greatly reduces the risk of cervical cancer in the following decade, but the protection weakens with time and is substantially less 15 years after the last screen," these researchers wrote. "In the light of increasing life expectancy, it would seem inappropriate for countries that currently stop screening between the ages 60 and 69 years to consider reducing the age at which screening ceases."

According to Dr. Subhakar "Sub" Mutyala, Associate Director of the Baylor Scott & White Cancer Institute and Associate Professor at Texas A&M College of Medicine in Temple, Texas, "This study shows the importance of pap smears for women. When women had routine and negative pap smears from ages 50-64, they had less cancer later in life."

Dr. Mutyala added, "It is important to note that although the risk of cancer is reduced, until more data comes out, pap smears should continue for women late into life."

The authors mentioned a couple limitations of their study. First, the data used did not include information on any health or lifestyle risk factors. Second, these findings may not be applicable to the general population because the study only considered one type of cervical cancer lesion.

This study was published on January 14 in PLoS Medicine.

Cancer Research UK provided funding.

Review Date: 
January 14, 2014