Apple CEO Steve Jobs' cancer scare illustrates another risk for the companies he leads - what would they do without him?

Apple CEO Steve Jobs maybe the most approved-of US CEO, carries a reputation as a visionary leader, and is seen as integral to Apple and Pixar; however, his cancer operation has led investors to consider what would happen if he passed away.

This charming man

Industry analyst Rob Enderle told Associated Press (AP): "What makes him very hard to replace is his charisma."

Analyst Michelle Gutierrez of Schwab Soundview Capital Markets said: "He's iconic. He's very much tied to the Apple name and the driving force behind Apple's re-emergence. If anything happens to him, it'll be a big blow to the company."

While analysts say they are confident that Apple's existing management team can lead Apple while Jobs recovers, the company's plans for a successor are unclear.

Succession planning?

Apple vice president of worldwide corporate communications Katie Cotton told AP that Apple does have such plans.

A report on CNN/Money last month suggested Apple may be forced to recruit a co-CEO to handle operational; matters at the company.

That report said: "I wrote a while back that Jobs needed to bring on a co-CEO to help him with the operational side of Apple so he could stick to the vision thing, but he hasn't done that."

Recent rumours from within the music industry have suggested Apple is engaged in identifying such help, with some insiders suggesting the company may be speaking with former chariman and CEO of the Warner Music Group, Roger Ames. This rumour remains unconfirmed.