Apple is due to release their quarterly sales report and is expected to announce a huge 50% hike due to holiday shoppers interest in the Apple iPad and iPhone; however there are concerns over the health of Apple chief Steve Jobs.

According to an article over on Reuters, the announcement that Steve Jobs was taking an unspecified length of medical leave without an inkling of any return date has left investors in an info void and that the announcement has caused Apple shares to tumble over 6% in European trading.

Global technology specialist at Nomura, Richard Windsor has said, “Steve Jobs is seen by the market to be a major force in Apple’s strategic direction. If his pancreatic cancer has returned, one could be quite worried.”

However; Apple hasn’t dwelt on the health of their CEO and Jobs has asked people to respect his privacy in the matter. Tim Cook, COO of Apple is to take over the helm and is to inform investors what Apple intends to do with its $50 billion+ lump of investments and cash.

Benchmarks for Apple’s fiscal 1st quarter by Wall Street are sales of about 4 million Mac computers, 5.5 million Apple iPad units and 15.5 million iPhone units, these figures include the holiday shopping season.

According to Thomson Reuters I/B/E/S, on Tuesday after the close of regular trading hours it is expected that Apple will announce earnings of $5.40 per share on revenue of $24.4 billion.