Kansas City, Mo. ? Federal prosecutors want Robert Courtney, the Kansas City pharmacist convicted of diluting chemotherapy medications, resentenced because they claim he broke a promise not to appeal his sentence.

Courtney was sentenced to 30 years in prison in 2002 after pleading guilty to diluting pharmaceutical drugs for seriously ill patients and keeping the profits. Prosecutors have said his dilutions could have affected 4,200 patients and about 98,000 prescriptions.

Courtney is serving his term at the federal prison in Greenville, Ill., and prosecutors have asked the 8th U.S. Circuit Court of Appeals to return him to Kansas City for a new sentence. Prosecutors argue Courtney’s plea bargain included a promise not to appeal his sentence.

“The remedy for breach spelled out in the plea agreement is that the United States is released from its obligations … but Courtney is bound by his guilty pleas,” federal prosecutor Gene Porter wrote in a motion filed with the court. “Thus, the district court could resentence Courtney without being bound by the 30-year sentencing cap agreed to by the parties.”

Last month, the Supreme Court sent Courtney’s case back to the St. Louis-based 8th Circuit for reconsideration of his sentence. It was part of a larger ruling that invalidated sentences for 450 defendants who claimed the federal guidelines under which they were sentenced are unconstitutional.

Courtney attorney J.R. Hobbs declined to comment Friday on the prosecution’s request. But Courtney’s attorneys have said they looked forward to an appeals court reconsidering Courtney’s sentence based on the new standard of review required by the Supreme Court.