08/20/2009 05:12 am ET | Updated May 25, 2011

Beastie Boys Cancel Lollapalooza Show Over Adam Yauch's Cancer Surgery

The Beastie Boys' Adam Yauch announced Monday that he has a cancerous tumor in his salivary gland and will undergo surgery next week, forcing the band to cancel its upcoming shows and postpone the release of its new album.

Among the canceled dates are two Chicago shows: August 6th at the Congress Theater and and August 8th gig headlining Lollapalooza.

In a video announcement on the band's web site, Yauch, 43, apologized to fans for having to cancel shows but said the cancer had been caught early and was treatable.

The surgery, Yauch said, will not affect his vocal cords.

"The good news is that they did scans on my hold body and it's only localized in this one area and it's not in a place that affects my voice," Yauch said. "It's a bit of a setback and a pain in the ass, but it's something that's very treatable."

Watch the full announcement: