The tests were carried out on patients already diagnosed with breast cancer to decide what treatment would be most effective. It is not yet known what effect this error will have on the patients.

An urgent investigation is now to be carried out by The Care Quality Commission into the treatment of breast cancer patients by Sherwood Forest Hospitals NHS Trust which runs King’s Mill Hospital in Sutton-in-Ashfield and Newark Hospital.

Linda Millband, a clinical negligence solicitor at Thompsons Solicitors said “Receiving the right treatment at the right time is paramount to each and every cancer patient. It is not yet known if the errors with these tests have had a negative effect on the patients concerned but if it transpires that they have then clinical negligence claims for compensation may be possible.”