Women who have been treated for precancerous cervical lesions will see their cancer risk decreased to normal after three "all clear" screening result, Dutch researchers say.
The women are then able to continue screening for cervical cancer on the same schedule with the general public, they added.
"The question is how we have to follow women who have been treated for precancerous cervical lesions," said lead researcher Dr. Chris Meijer, of the pathology department at the Vrije University Medical Center in Amsterdam.
The answer appears related to two years worth of normal test results after treatment.
In the study, Meijer team looked at the effectiveness of follow-up screening among 435 women treated for cervical precancerous lesions between July 1988 and November 2004. The women were given a Pap test for cervical cancer screening and also tested for the virus associated with cancer - human papillomavirus, or HPV - in months 6, 12 and 24 after treatment. If abnormal test results, they return to normal testing, which in the Netherlands is once every five years.
The risk of developing precancerous cervical lesions or new cervical cancer for five years is 16.5 percent.
However, among women who have three normal Pap and HPV tests, the risk dropped to 3 percent in the same period, which is the same risk seen in women who never had precancerous cervical lesions, the researchers noted.
In addition, the Meijer group found that adding HPV testing to make inspection a year is not necessary for women who had negative test at six months.
Women treated for precancerous cervical lesions who developed recurrent disease needs to screening with Pap and human papillomavirus testing, but the best regimen for long-term follow-up is unclear, the researchers said.
This report is published in the 27 April online edition of The Lancet Oncology.
American Congress of Obstetricians and Gynecologists recommends that women aged 21 to 30 be screened for cervical cancer every two years and that women over 30 who have had three negative (normal) Pap and HPV tests in a row are checked every three years.
Meijer think that although the protocol for screening women over 30 in the United States every three years, can safely be extended to five years.
However, women who had abnormal tests after treatment need additional tests, because their risk was high again during the next five years, Meijer noted.
Commenting on this study, Dr. Elizabeth A. Poynor, a gynecological oncologist and surgeon at Lenox Hill Hospital pelvis in New York City said that "it provides a framework for how to follow people after they have been treated for precancerous cervical lesions."
To Poynor, important message is that if a woman does not have a relapse after two years, her risk of developing precancerous lesions of the cervix go back to the same risk as women who had never had pre-cancerous cervical lesions - that is, they have the same risk as other women in the population general.
"These women could return to acceptable screening in the United States, which is slightly more stringent [than that in the Netherlands]," he said. "Women's exactly two years after being treated for precancerous cervical lesions can be assured that they return to the population at risk."