John Wetton, the prog-rock stalwart who's served as singer, songwriter and bassist for a lengthy list of acts that includes Asia, King Crimson and UK, recently underwent major surgery to remove a cancerous growth.

According to Wetton's official site, the procedure took place May 16. The post thanks his surgical team and adds that he's "beyond grateful for the wonderful wishes and prayers" he received from fans in the days leading up to his admittance.

Wetton also shared the news via Twitter, filling in followers with a pair of tweets that he posted before and after surgery:

While Wetton recuperates, Asia is prepping the arrival of Axis XXX Live in San Francisco MMXII, a multi-format concert recording scheduled for release as a DVD/two-CD and Blu-ray title this summer. Presenting a night on the tour for the band's 2012 LP XXX, it captures one of guitarist Steve Howe's final dates with Asia before retiring from the lineup to concentrate on his duties with Yes.

Calling it "a journey through Asia's history, from ‘Alpha to Omega’ and more, in the beautiful setting of the Regency Ballroom, San Francisco, California," Wetton is quoted in the Axis XXX press release as promising "Much newer material is aired, plus the band’s vintage hit songs performed by all four original members of Asia. A stunning recording, an unmissable treat for any Asia fan, new or old."

Asia's most recent studio effort, Gravitas, arrived in March 2014.

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