He added: “I said, ‘Dad’s got cancer’. She said, ‘Is that bad, Dad?’
“I said, ‘Yes, it’s very serious but I think it should be OK. Modern medicine’s great and if anything changes I’ll let you know’.”
Merlin added his wife Lucile was “incredibly upset” by the news, which he shared over the phone.
The First Dates star began suffering from stomach pain back in June, but put this down to a scar tissue stemmed from a car accident aged 20.