The General Medical Council has suspended a leading surgeon who is accused of performing up to 1,150 "unnecessary, inappropriate or unregulated" breast operations.
Ian Stuart Paterson, who worked at various NHS hospitals over a period of 18 years, could face criminal charges over his conduct, with nearly 100 patients pursuing legal claims against him.
It is alleged that Paterson misdiagnosed 450 healthy women with breast cancer, before performing an unnecessary procedure known as a 'lumpectomy' on them.
The surgeon is also accused of carrying out a 'cleavage-sparing' operation on a further 700 women, leaving breast tissue around their cleavage for aesthetic purposes after a mastectomy.
Cleavage-sparing surgery breaches UK medical guidelines, which stipulate that all breast tissue must be removed during the mastectomy.
In addition to Paterson's suspension, the GMC is carrying out an investigation into his conduct during a career which included stints at Solihull Hospital, Good Hope Hospital and Spire Hospital Parkway.
A GMC spokesman said: "Dr Ian Paterson's registration is currently suspended, following an Interim Orders Panel meeting on 29 October 2012. This means the doctor cannot work as we investigate concerns about his fitness to practise."
Paterson claimed he was helping investigators with their inquiries. He said: "I am co-operaing fully with the GMC investigation and cannot comment on any of the issues raised because of my duty of patient confidentiality and the ongoing investigation."