Gov. Phil Murphy will undergo surgery Wednesday morning to remove a likely cancerous tumor from his kidney, his office said.

Murphy, 62, revealed last month he was diagnosed with a 3-centimeter tumor on his left kidney that is 92 percent likely to be malignant. He said doctors wouldn’t know until if it’s cancerous after his surgery.

The governor’s office disclosed the date of the surgery Tuesday afternoon.

Lt. Gov. Sheila Oliver will serve as acting governor ”until further notice,” Murphy’s office said.

Murphy has said doctors believe his prognosis is good.

“We caught it early,” he told NJ Advance Media in an interview at his Middletown home last month. “We consider ourselves incredibly lucky.”

The governor will undergo a procedure called a partial nephrectomy, which means doctors will remove part of the kidney but not the whole organ. The invasive surgery, which involves doctors freezing the kidney to extract the tumor, will take a few hours, Murphy said.

Murphy said he expected to be in the hospital for a few days and then spend a few weeks after that recovering at home.

Patients with kidney cancer that has not spread beyond the organ have a 93 percent chance of surviving at the five-year mark.

Murphy’s surgery will take place at an undisclosed New York City hospital. The governor said that’s not a slight on New Jersey’s hospitals — his longtime doctor and the doctor’s associated are based in the city.

Murphy, a progressive Democrat, has used his illness to draw attention to the fight to improve health care in America.

“I am lucky to have a small piece of plastic in my wallet that provides me real peace of mind — a health care policy membership card that provides benefits which are actually worth more than the card my name is printed on,” the governor said during a speech in Washington, D.C., last week.

“And I am lucky that I am not one of the countless thousands upon thousands of New Jerseyans who cannot say the same," he added. “And that angers me.”

Brent Johnson may be reached at bjohnson@njadvancemedia.com. Follow him on Twitter @johnsb01.

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