Yauch was diagnosed with a cancerous tumor in his left parotid (salivary) gland last week.

The good news is that the tumor was caught early and is localized in one area, so it’s very treatable. Yauch’s vocal cords will not be affected by the tumor or surgery.

The bad news is the treatment requires surgery and several weeks of additional treatment, which means all upcoming shows on the Beasties’ schedule have been canceled and the band’s latest album Hot Sauce Committee Part 1 has been delayed.

Yauch issued a message to fans via a video posted on BeastieBoys.com.

“I just need to take a little time to get this in check, and then we’ll release the record and play some shows,” Yauch explained. “It’s a pain in the neck (sorry had to say that) because I was really looking forward to playing these shows, but the doctors have made it clear that this is not the kind of thing that can be put aside to deal with later.”

The cancellations of the Beasties’ tour is especially bad news for the summer festival circuit, leaving organizers of All Points West, Osheaga Music & Arts Festival, Lollapalooza, Outside Lands and Austin City Limits in the market for a new headliner.

See Yauch’s entire statement at BeastieBoys.com.