An American man is suing his doctor after waking up from an operation that he had expected to be a simple circumcision to discover that part of his penis had been amputated.

Phillip Seaton, 64, of Waddy, Kentucky, is suing Dr John Patterson, who performed the 2007 surgery.

The doctor said he saved the truck driver's life when he cut off part of the man's penis after discovering a rare and deadly cancer. But Mr Seaton told a jury he wanted to escape from the hospital when he learnt it was removed without his knowledge.

"What I saw was not a penis. What I saw was cancer," Dr Patterson, a urologist, told the Shelby County Circuit Court. The doctor said he removed less than an inch of Mr Seaton's penis. The rest was amputated by another doctor later, said Dr Patterson's lawyer, Clay Robinson.

Mr Seaton's wife, Deborah, is also a plaintiff in the suit, which seeks unspecified damages for "loss of service, love and affection".

In an earlier testimony, Mr Seaton described the moments after being told part of his penis had been removed. "I pulled the dressing down, and I didn't see nothing," he said. "Then I came out of the restroom and I said, 'I'm getting the hell out of this damn hospital.'"

Mrs Seaton testified that if the doctor had consulted her after finding the cancer, she would have advised him to halt the surgery. "It's his body," she said. "He should have a say in it."