A breast surgeon who carried out unapproved mastectomies was a “nightmare” to work with, a colleague has told an inquest into the death of one of his cancer patients.

Ian Paterson, who was educated in Bangor, is currently serving a 20-year jail sentence after being convicted of 17 counts of wounding with intent and three counts of unlawful wounding in 2017.

He performed unauthorised “cleavage-sparing” mastectomies, which left behind breast tissue for cosmetic reasons but increased the risk of cancer returning.

Former breast cancer patients 43-year-old Chloe Nikitas, whose judge-led inquest last week was the first of 62 to be heard at Birmingham and Solihull Coroners Court over the next eight months, and Elaine Turbill, 63, whose inquest is being held this week, were subjected to cleavage-sparing mastectomies by Paterson and both later died of metastatic cancer.

Giving evidence on Wednesday at Mrs Turbill’s inquest, Paterson’s former colleague and consultant radiologist at Solihull Hospital Dr Chris Fletcher, said the pair had a “frosty” relationship at times.

He told the inquest they had worked together between 1998 and 2011 and that reviewing mammograms from Paterson’s patients made up at least “90%” of his workload at both the NHS and privately at Spire hospitals.

Dr Fletcher said their relationship was “complex” and “difficult” because of the way Paterson worked and he ended up making a complaint about him.

He said: “He was a nightmare. He was quite aggressive and quite demanding in a way I had never come across before.

“At a time where he was ingratiating himself with me, you almost felt he was using flattery to get you to do things. Then it became rocky again.”

He said multidisciplinary meetings between NHS colleagues to discuss the treatment of their patients were “always difficult”.

He said: “[Paterson] always tried to run the show. We had a period where he was flooding me with work and I was struggling to cope.

“He was being very demanding and I had to make a complaint to management to try and calm the situation because he was sending so much stuff we couldn’t cope.”

Dr Fletcher said their relationship deteriorated further after he signed a letter, alongside other colleagues, raising concerns about Paterson.

He said: “After 2007, when I ‘sided with the enemy’ as he saw it, we had a very frosty relationship after that and he only spoke to me when he had to.

“He was very difficult to work with.”

Dr Fletcher said he initially believed Paterson was just an “efficient and competent surgeon” but started to become concerned with the way he was carrying out mastectomies when he discovered a tumour on a patient’s mammogram that Paterson had missed when operating on them.

He told the inquest: “There was a tumour very high up and he had obviously missed it. He had been arrogant and just done what he wanted to do and hadn’t looked at the mammogram.

“We were all a bit shellshocked and embarrassed by that. Nobody ever flagged it as perhaps it should have been flagged.”

Paterson has agreed to give evidence remotely from prison at Mrs Turbill’s inquest on Thursday.

Coroner Richard Foster said Paterson has requested he only give oral evidence one day a week so as to “minimise disruption to his prison regime”.

Judge Foster said: “All witnesses have had to sacrifice aspects of their daily lives in order to give evidence, no doubt to considerable inconvenience to themselves and their families. Many witnesses are long since retired.

“In the same way, it is not unreasonable to expect Mr Paterson to sacrifice aspects of his settled prison regime in order to provide evidence.”

The inquest continues.