Apple Inc chief executive Steve Jobs underwent a liver transplant at a Tennessee hospital and has an excellent prognosis, the hospital that performed the operation confirmed on Tuesday.

Jobs, 54, received the transplant because he was the sickest patient on the waiting list at the time a donor organ became available, the Methodist University Hospital Transplant Institute said in a statement on its Website.

Mr. Jobs is now recovering well and has an excellent prognosis, the statement said. James Eason, program director at the institute and the hospital's chief of transplantation, added that the confirmation had come with Jobs's permission.

The hospital did not release details of Job's condition or when the operation was performed, but the Wall Street Journal reported over the weekend that the transplant took place about two months ago.

Hospital spokeswoman Ruth Ann Hale did not immediately respond to a request for comment on Jobs' condition. A prognosis refers to a doctor's prediction regarding the probable course of a disease, disorder or injury.

Apple shares have often fluctuated on speculation about Jobs' health. The executive, considered by many investors to be the driving force behind Apple's reputation for innovation, was treated in 2004 for a rare form of pancreatic cancer called an islet-cell, or neuroendocrine, tumor.

But he appeared gaunt at an Apple event in the summer of 2008, setting off a storm of speculation about his health that failed to abate in the ensuing months.

In January, after initially blaming his weight loss on a hormone imbalance, he announced his medical leave, saying his health issues were more complex than originally thought.

He has not been heard from since, though a Reuters witness spotted Jobs at Apple's campus in Cupertino, California, on Monday and Jobs was quoted in a company press release.

The company would not say whether Jobs is off medical leave and back at work. Apple has said repeatedly that it looks forward to his return at the end of June.

A FULL LIFE

Jobs is viewed as the key visionary driving the company's product development and the mastermind behind iconic products such as the iPod and the iPhone.

But analysts say Wall Street has become much more comfortable with other key executives in Jobs's absence.

Apple shares have surged around 60 percent this year, despite falling 10 percent following Jobs announcement of medical leave.

Methodist's confirmation comes as some newspaper and Internet reports speculated on whether Jobs waited his turn for a transplant.

In the United States, 15,771 people are waiting for a liver transplant, according to the Organ Procurement and Transplantation Network of the U.S. Department of Health and Human Services.

The hospital said Jobs underwent a complete transplant evaluation and was listed for transplantation in accordance with policies laid down by the Transplant Institute and the United Network for Organ Sharing (UNOS) policies.

We provide transplants to patients regardless of race, sex, age, financial status, or place of residence, the hospital said in its statement.

Pancreatic cancer often spreads to the liver, but it is not clear if Jobs received a transplant for that reason.

Doctors without knowledge of Jobs's specific condition have said if the tumor migrated to the liver from the pancreas, a liver transplant may be an effective treatment and he could lead a normal life.

About 70 percent of liver transplant patients are still alive three years later, UNOS estimates.

(Additional reporting by Patrick Rucker in Washington; Editing by Edwin Chan, Peter Cooney and Muralikumar Anantharaman)