Thanks in large part to an early detection, a full recovery is expected, and he should be ready to work again in six weeks if anyone "is looking for a great coach."
"I appreciate the concern and prayers of the Seminole Nation," Amato said in a statement released by the school. "The prognosis is optimistic, which is very encouraging, and with the grace of God and the support of my family and friends, I will get through this."
The issue was originally discovered in December.
"I wanted to wait and tell people until after I had a chance to tell my dear friend, coach [Bobby] Bowden, face to face," Amato said. "However, now that the word has spread, I want to assure everyone that I will tackle this challenge just like I've tackled coaching throughout my career -- full speed ahead."
Amato spent 18 years as an assistant to Bowden before taking over in Raleigh, where he spent seven seasons before being replaced by Tom O'Brien. Amato returned to Bowden's staff, though he was not retained by new Florida State coach Jimbo Fisher.
Heather Dinich covers the ACC for ESPN.com. Information from The Associated Press was used in this report.