Supertramp have canceled their upcoming European tour because of leader Rick Davies' health issues. According to the band's website, "Davies was recently diagnosed with multiple myeloma and has begun aggressive treatment to combat the disease." WebMD defines multiple myeloma as "a cancer that affects plasma cells, a kind of white blood cell found in the soft insides of your bones, called marrow."

The band hasn't played live in five years, and was planning on hitting the road on Nov. 3 for a 25-city tour scheduled to wrap up with a sold-out show in Amsterdam on Dec. 11. The Supertramp Forever tour would have been hits-filled sets that spanned the group's career.

Following the news of the cancellation, Davies issued a statement. “I was really looking forward to returning to Europe and playing with the band again, and I’m sorry to disappoint everyone who has overwhelmingly supported the upcoming tour," he said. "Unfortunately, my current health issues have derailed me, and right now I need to focus all of my energy on getting well.”

All of the shows on the tour -- including stops in Madrid, Paris and London -- have been canceled, and there are no plans at this time to reschedule any of them.

Davies formed Supertramp in 1969 in London with Roger Hodgson, who quit the group in 1983. Five years later, Davies broke up the band. But in 1996, he revived Supertramp while working on a solo album. They broke up again in 2002, but reunited in 2010 for the 70-10 tour in support of their 40th anniversary.

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