June 17 (UPI) -- Megadeth is cancelling a number of shows following Dave Mustaine's diagnosis with cancer.
The heavy metal band canceled the majority of its summer tour Monday as the 57-year-old singer and musician undergoes treatment for throat cancer.
Mustaine, who co-founded Megadeth with bassist David Ellefson in 1983, shared the news in an Instagram post Monday.
"I've been diagnosed with throat cancer. It's clearly something to be respected and faced head on - but I've faced obstacles before. I'm working closely with my doctors, and we've mapped out a treatment plan which they feel has a 90% success rate. Treatment has already begun."
"Unfortunately, this requires that we cancel most shows this year. The 2019 Megacruise will happen, and the band will be a part of it in some form. All up to date information will be megadeth.com as we get it. Megadeth will be back on the road ASAP."
Mustaine said he and his bandmates, Ellefson, Kiko Loureiro and Kirk Verbeuren, are working on a new album, the followup to 2016's Dystopia. He promised to "keep everyone posted" about his health.
"I'm so thankful for my whole team -- family, doctors, band members, trainers, and more," the star said.
Megadeth had several shows scheduled for the summer, including an Aug. 9 performance at the Illinois State Fair.
"While we are obviously disappointed that Megadeath [sic] won't be playing the Illinois State Fair, our main concern is for Dave Mustaine," fair manager Kevin Gordon said in a statement to NBC 5. "We wish him a fully recovery and look forward to having Megadeath back to the Illinois State Fair in the future."
The MegaCruise, a cruise with stops in San Diego, Calif., and Ensenada, Mexico, is scheduled to take place Oct. 13-18.