In an e-mail message on Sunday to employees released by Apple, he said he will be off to recuperate during August and expects to return to work in September. The message did not specify where he underwent the surgery.

He identified his cancer as an islet cell neuroendocrine tumour, which he described as rare and said could be cured by surgical removal if diagnosed early. He said his was caught early and would require no chemotherapy or radiation treatment.

A far more deadly - and common form - of pancreatic cancer is adenocarcinoma, he said.

'I mention this because when one hears 'pancreatic cancer' , one immediately encounters this far more common and deadly form, which, thank God, is not what I had,' he said in the message.

During his absence, Apple will be run by Mr Timothy Cook, the company's executive vice-president of worldwide sales and operations. Mr Cook said the current management team has worked with Mr Jobs for many years, and that experience will guide them through the next month.

'Steve is an extremely hands-on CEO,' he said. 'We have some very clear priorities for the company for months to come.'