In a statement Sunday, the Indians said Carrasco was diagnosed at the Cleveland Clinic "with chronic myeloid leukemia, a treatable form of leukemia and has since been cleared to resume strength and conditioning workouts and throwing activity to tolerance."
The team said that Carrasco is regularly being reevaluated and that there is no timetable for his return to pitching in a game.
Carrasco had revealed on Saturday that he was being treated for leukemia and that it was "under control." He said he expected to be back with the Indians "at the end of July."
The Indians put Carrasco on the injured list on June 5 with an unspecified diagnosed blood disorder, saying he was "stepping away from baseball activities to explore the optimal treatment and recovery options" and that they expected him to return "at some point this season."
The Indians put Carrasco on the injured list on June 5. He was 4-6 with a 4.98 ERA in 12 starts this season before going on the IL.
Carrasco, 32, has developed into one of the AL's steadiest pitchers in recent years. He won 17 games last season and went 18-6 in 2017, when he finished fourth in the AL Cy Young Award voting.
He signed a four-year, $47 million contract in December. In 10 seasons, all with the Indians, he is 83-68 in 219 appearances (183 starts).
The Associated Press contributed to this report.