Just last month, the Beastie Boys became the third rap group ever to be inducted into the Rock and Roll Hall of Fame -- but Yauch wasn't able to attend the induction ceremony.
"Hello My Friends -- while I'm grateful for all the positive energy people are sending my way, reports of my being totally cancer free are exaggerated," he wrote on the group's official website in April. "I'm continuing treatment, staying optimistic, and hoping to be cancer free in the near future."
Yauch founded the Beastie Boys alongside his friends Mike "Mike D" Diamond and Adam "Ad-Rock" Horowitz in 1979. The legendary rap group's most recent album, Hot Sauce Committee, Pt. 2, was released last May.
The hip hop icon is survived by his wife, Dechen Wangdu and their daughter, Tenzin Losel Yauch.