Women With CIN3 Need Continued Follow-Up Throughout Old Age

Women in whom cervical intraepithelial neoplasia grade III (CIN3) was previously diagnosed and treated were at substantially increased risk for developing cervical or vaginal cancer when they reached age 60 years, researchers reported in the British Medical Journal.

While the researchers reaffirm that only a small minority of women treated for CIN3 will develop and die from cancer, they say the risk is 2 to 3 times higher than the general female population, and age appears to be a significant contributing factor.

“The main implication of this study is that women previously treated for CIN3 also need surveillance in old age, perhaps as long as it is practical to visit a physician or a nurse to take a smear,” the authors, from Sahlgrenska University Hospital and Karolinska Institute in Sweden, concluded. “Emphasis should be placed on continued surveillance in old age, rather than on follow-up for a specified number of years after treatment, the strategy suggested, for instance, in the new US guidelines.”

When compared with the general female population, women with a previous CIN3 diagnosis had a standardized mortality ratio of 2.34 (95% confidence interval, 2.11 to 2.61), the researchers reported. After age 60 years, and again after age 70 years, there was a steep increase in mortality risk.

Using data from the Swedish Cancer Registry-which contained information on 150,883 women with CIN3, of whom 1,089 had a diagnosis of invasive cervical cancer and 147 had a diagnosis of vaginal cancer-the researchers reported that after age 75 years, the incidence rates exceeded 100 per 100,000. The background risk for cervical or vaginal cancer was 8.9 per 100,000 women in the population at large and 10.2 per 100,000 in women aged 70 years, they reported.

There was also a steep increase in risk of death with increased age after a previous diagnosis of CIN3, with the risk more than doubling after 30 years following treatment, compared with the general population. In women aged 72 years, death rates accelerated to 50 per 100,000 women. Death rates also increased with age at treatment, they found.

Still, the authors sought to reassure patients that treatment for CIN3 is effective in protecting them from cervical cancer. The point of the findings, they said, was to ensure close follow-up care and continued attention as these women age.

Pertinent Points:
- Women previously diagnosed with and treated for CIN3 were at substantially increased risk for the development of cervical or vaginal cancer when they reached aged 60 years.
- The risk continues to accelerate as the women age.

References:

Strander B, Hallgren J, Sparen P. Effect of ageing on cervical or vaginal cancer in Swedish women previously treated for cervical intraepithelial neoplasia grade 3: population based cohort study of long term incidence and mortality. BMJ. 2014;348:f7361. Available here.