Region Midtjylland has admitted being responsible for an IT system failure that caused 27,000 women to be involuntarily unregistered to a screening program for cervical cancer, leaving hundreds in risk of developing early stages of the disease.

The Jutland regional council is in charge of calling in women all over the nation for the screenings.

Ole Thomsen, the head of the region's health department, said the errors occurred between 1981 and 2007, when an IT system was updated to coincide with the nation's structural reform.

"I can explain what happened, but not why it happened," Thomsen told DR Nyheder. "The system generated codes and unregistered the women. Now we are going to find out what went wrong to make sure that it won't happen again."

Only 8,000 of the women went to the screenings on their own, while the remaining 19,000 have been called in to get an exam as soon as possible.

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Also checking on breast cancer register
After the system fail was revealed yesterday, the regions are now looking into the breast cancer screening register to make sure that the same errors have not happened there. 

"We have no real reason to believe that there has also been an error in the breast cancer screenings. It is a different and much more modern system," Thomsen said. "But we need to be certain because there are legitimate doubts concerning the systems we use." 

400 women may need surgery
According to statistics from cancer fighting association Kræftens Bekæmpelse, around 400 women may have evolved precancerous lesions without knowing it and will need to have a cone biopsy of the cervix.

“Such an error must never occur,” Leif Vestergaard Petersen of Kræftens Bekæmpelse wrote in a press release. "Nineteen thousand women haven't received the security this screening offers. In the worst cases, that could lead to cancer that would have been observed otherwise.”

The screening programme is offered for women aged 23-49 every third year while women aged 50-64 are called in every fifth year. Since the introduction of the screenings, cervical cancer rates have been reduced by about 60 percent.

It has not yet been confirmed if there is a connection between any cases of cancer and the system failure, but Thomsen said that if that is the case, the affected women or their relatives should complain to the patients' insurance association, Patientforsikringen.

"We know it is very unpleasant for the women to receive this news. But it is also unpleasant to deliver. We have made all efforts to avoid it happening again," he said.

The head of Patientforsikringen, Karen-Inger Bast, said that any woman who has gotten cancer because they were not called in for a screening would have a good chance of receiving compensation.