TUESDAY, Jan. 14, 2014 (HealthDay News) -- Women who have been diagnosed with and treated for precancerous cells on the cervix may be at increased risk for developing and dying from cervical or vaginal cancer, new research suggests.
However, the researchers added that the overall risk of cervical or vaginal cancer is still low for women who have been diagnosed and treated for abnormal cells on the cervix.
The study authors analyzed data from more than 150,000 Swedish women who were treated for abnormal cells on the cervix. Of those, nearly 1,100 were later diagnosed with invasive cervical cancer and about 150 were diagnosed with invasive vaginal cancer. There were more than 300 deaths from cervical cancer and about 50 deaths from vaginal cancer.
As women who had been treated for precancerous cells on the cervix grew older, their risk of cervical or vaginal cancer increased. The risk accelerated after age 60 and again after age 75, according to the study. The researchers found that incidence rates of cervical and vaginal cancer in the oldest group of women exceeded 100 per 100,000 women.
The more recently women had been treated for abnormal cells on the cervix -- and the older they were at the time of treatment -- the greater their risk of cancer. Those who were treated at ages 60 to 69 had a five times higher risk than those treated at ages 30 to 39, according to the study.
The findings were published online Jan. 14 in the journal BMJ.
The risk of death from cervical or vaginal cancer also increased with age among women who had been treated for abnormal cells on the cervix, according to a journal news release. Thirty years after treatment, these women were more than twice as likely to die from cervical or vaginal cancer than those in the general population. At age 72, death rates from these cancers increased to 50 per 100,000 women, the study found.
The older a woman was when she was treated for precancerous cells on the cervix, the greater her risk of death from cervical or vaginal cancer, according to the news release.
The findings show that women who have been treated for abnormal cells on the cervix "should be followed up in old age," said researcher Bjorn Strander, from the University of Gothenburg, and colleagues at the Karolinska Institute, both in Sweden.
It is worrying that the study found that women who received treatment more recently were at greater risk of developing cervical and vaginal cancer, Dr. Marc Arbyn, from the unit of cancer epidemiology of the Scientific Institute of Public Health, in Brussels, Belgium, said in an accompanying editorial.
Arbyn called for research to identify signs that predict a woman's future risk of cervical and vaginal cancer.
"Measures should be taken to assure full compliance with follow-up after treatment of cervical pre-cancer," he said.
The U.S. National Cancer Institute has more about cervical cancer prevention.