Team owner Jim Irsay made the announcement Monday during a somber and sometimes emotional news conference at the team complex.
“I am optimistic. I feel with every fiber of my body and I know Chuck feels that he can beat this thing,” Irsay said.
Offensive coordinator Bruce Arians will serve as the interim coach in Pagano’s absence. Irsay said that Pagano requested that Arians coach the team while he is undergoing treatment.
Pagano told ESPN senior NFL analyst Chris Mortensen in a text that he “will be back soon.”
Irsay, however, said it was unlikely Pagano would be able to assume full-time coaching duties this year.
“I think it’s unlikely he’ll be all-in as the head coach the rest of this season,” Irsay said. “He may be able to come back and be in the press box or something.”
Dr. Larry Cripe, the physician treating the coach at Indiana University’s Simon Cancer Center, said Pagano has acute myeloid leukemia, where the bone marrow is producing abnormal white blood cells that interfere with healthy blood cells. Symptoms can include weakness, weight loss and easy bruising or bleeding. Treatments can include chemotherapy, drugs and radiation therapy.
Irsay said Pagano’s wife pushed him to see the doctor after noticing unusual bruising on the coach’s body.
“He is ready to take this fight on and he is a fighter,” Irsay said.
Pagano waited until the Colts’ bye week last week to be checked out after experiencing extreme fatigue and bruising, starting in training camp.
Pagano believed he was experiencing football fatigue, but a blood test early last week revealed the diagnosis of leukemia.
The initial phase of treatment usually requires a hospital stay of four to five weeks, though Irsay later acknowledged he expected Pagano to be in the hospital at least six weeks.
Cripe said Pagano began the “arduous” treatment last week and that many adults do recover from the disease. For now, Pagano is being kept in a “protected” hospital environment where air is filtered and hand-washing is essential.
Pagano was admitted last Wednesday evening; the team had a bye this weekend and players and the assistants, other than Arians, were not told Pagano was ill until Monday morning.
Cripe said that Pagano is handling the chemotherapy treatments well so far. The goal of the treatment is to “cure” Pagano, which means the disease remains in remission for 3 to 5 years.
“This is not an easy day for any of us,” Arians said. “It was not the way I ever dreamed about addressing a group like this. But I know he’ll get through it.”
General manager Ryan Grigson said he was not yet certain how the rest of the coaching duties would be split up, though he expected all of the assistants to pitch in.
The 51-year-old Pagano was hired in January after serving as the Baltimore Ravens‘ defensive coordinator.
Pagano earned his first win Sept. 16 against the Vikings. The Colts (1-2) had a bye last weekend.