Apple CEO Steve Jobs had a liver transplant in Tennessee about two months ago, according to an unconfirmed story in the Wall Street Journal.

He has been on medical leave from the company since January to treat the fact that he appeared to be starving to death.

Jobs is expected to return to Apple on schedule at the end of the month, the story says, but may work part-time for a while, and Apple COO Tim Cook, who has been standing in for Jobs, may take on a bigger role.

Cook may get a seat on the Apple board soon.

Five years ago the private Mr. Jobs, now 54, disclosed that he had been operated on for a rare pancreatic cancer, that the islet cell neuroendocrine tumor had been removed in time, and that he needed no chemotherapy or radiation.

There has been a burning debate ever since about just how much medical information a man in Jobs' position, who is seen as the heart and soul of Apple, is required to share with stockholders and the public in general.

The debate intensified when he appeared gaunt and emaciated.

Apple at first put his appearance down to a "common bug." Jobs then ascribed it to a hormone imbalance that was "relatively simple and straightforward" to treat. That was right before he took a five-month medical leave confessing that it was more complicated than he had thought. He left Mr. Cook in charge. According to the Journal some members of Apple's board have been briefed weekly by his doctor.

Bloomberg reported in January that Jobs was considering a liver transplant.

The Journal quotes a specialist in pancreatic and gastrointestinal surgery, who has not treated Jobs, as saying his cancer probably metastasized to the liver.

He also said the transplant was "controversial because livers are scarce and the surgery's efficacy as a cure hasn't been proved," apparently "patients whose tumors have metastasized can live for as many as 10 years without any treatment so it is hard to determine how successful a transplant has been in curing the disease."

The Journal says there are no residency requirements for transplants and that the list of patients waiting for a transplant has been shorter in Tennessee than in many other states.

In 2006 the waiting list there was only 48 days versus a median 306 days nationwide but a variety of criteria have to be met to get an organ and a transplant can also be done from a living person who donates half of his or her liver, which is crucial to digestion and metabolism.