Summerfest's July 4 show at the American Family Insurance Amphitheater with Megadeth has been canceled, leaving the amphitheater dark for an evening.

Megadeth lead singer Dave Mustaine announced Monday that he was recently diagnosed with throat cancer.

“It’s clearly something to be respected and faced head on — but I’ve faced obstacles before," Mustaine said in a statement. "I’m working closely with my doctors, and we’ve mapped out a treatment plan which they feel has a 90 percent success rate. Treatment has already begun."

In a statement, Don Smiley, president and CEO of Milwaukee World Festival Inc., said: "Our hearts and prayers go out to Dave, his family and crew, at this time. All of us at Summerfest, along with our fans, extend our support and well wishes for a speedy recovery."

All of Megadeth's scheduled shows this summer have been canceled.

The Summerfest show was also set to feature Papa Roach, Pop Evil, Badflower and Light The Torch.

It was actually a replacement for a planned Ozzy Osbourne appearance, with Megadeth as an opener.

That show, and all of Osbourne's tour dates for 2019, were canceled back in April, after Osbourne fell and injured himself at home while recovering from pneumonia. Osbourne's Summerfest amphitheater show has been rescheduled for July 1, 2020.

Summerfest will not be scheduling a new show to replace Megadeth July 4 — the first time in the festival's history that there has not been a show in the amphitheater.

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Contact Piet at (414) 223-5162 or plevy@journalsentinel.com. Follow him on Twitter at @pietlevy or Facebook at facebook.com/PietLevyMJS.

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