A radiologist who failed to diagnose breast cancer in 28 women was allowed to continue working for more than a year after concerns were first raised about his work, it emerged last night.

The consultant radiologist, who has not been named, was suspended from duty at Trafford General and the North Manchester General last April after concerns were raised about his X-ray work.

A massive investigation, involving the rechecking of 2,500 mammograms, revealed that he had given the all-clear to 17 women with breast cancer whose chances of surviving the disease had been "significantly" hit by his misdiagnosis.

Doctors who examined his work also found that one woman's breast cancer was noticed only two years after the radiologist told her she did not have the disease.

Last night, hospital chiefs admitted that he had been questioned over his work six months into his new post but allowed to carry on for a further 17 months. They refused to say if further monitoring was ordered after the initial concerns were raised.

No mention of the earlier fears was made at a press conference on the matter on Tuesday.

David Cain, chief executive of the trust, said that concerns were raised after a few months, but that they were investigated throughly and dealt with.

He added: "No instances were raised of missing any serious breast diagnoses until April 2005, and the trust took immediate action."

It also emerged yesterday that one of the women who was wrongly told she did not have breast cancer by the radiologist is seeking compensation from Trafford healthcare NHS trust in an attempt to find out how the mistake happened.

Stephen Jones, the unnamed woman's solicitor, said she was not seeking retribution against any individual. She wants a proper inquiry about whether there were systematic failings in training and supervision which allowed the mistakes to happen, he said.