CHICAGO (AP) — A scathing new report by court-approved researchers paints a bleak picture of medical care in Illinois prisons, describing treatment delays, haphazard follow-up care, chaotic record keeping and a litany of other problems that may have cut short the lives of some inmates.

The 405-page report, which the Illinois Department of Corrections immediately disputed, was filed late Tuesday night in U.S. District Court in Chicago in a class-action civil suit against the agency that oversees 49,000 inmates statewide. The report concludes that “Illinois has been unable to meet minimal constitutional standards with regards to the adequacy of its health care program.”

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Within minutes of the filing, the agency issued a statement saying the report “uses a broad brush to paint an incomplete picture of the comprehensive medical system in place.” It said authors were wrong to draw sweeping conclusions after visiting just eight of 25 Illinois prison facilities.

The experts, who had access to thousands of prison records, also scrutinized a sample of 63 Illinois prisoner deaths from illnesses and found “significant lapses” in care in 60 percent of those cases, calling that rate “unacceptably high.”

The report cites many individual cases, including that of Edward Thomas.

Thomas was convicted of first-degree murder for throwing 20-year-old Kevin Tremble head first down a Chicago elevator shaft in an apparent gang-related dispute, according to filings in his criminal case. Even though Thomas pleaded for help as he began coughing up blood, the report says it took six months for doctors at the Hill Correctional Center in Galesburg to locate a softball-size cancerous tumor clinging to his neck area and lung. But it was too late. Thomas, at 48, died four months later on Jan. 30, 2013.

“The blatant disregard for this patient’s obvious symptoms … is stunning,” the report said. “Despite the patient’s repeated earnest cries for help, including several instances wherein he was essentially stating, ‘I think I have cancer,’ his symptoms were brushed off … until … this dying man could no longer be ignored.”

During his sentencing in 1984, a Cook County judge said Thomas had displayed “exceptionally brutal or heinous behavior indicative of wanton cruelty” and handed him an 80-year prison term.

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But inmates, even those imprisoned for murder, are entitled to better care, said Benjamin Wolf, a plaintiffs’ attorney and chief legal counsel of the ACLU of Illinois, which joined the lawsuit in 2013.

“The measure of justice of a society is how it treats its most vulnerable, including prisoners,” Wolf said. “No one sentenced these guys to suffer and die of inadequate health care.”

The report includes Thomas’ prison, age and the date of his death, but not his name. Knox County Coroner Mark Thomas, who performed the autopsy on Thomas, confirmed to The Associated Press that he was the inmate who died of lung cancer on Jan. 30, 2013 at the Galesburg prison. Thomas was the only inmate who died that day.

Inmate Don Lippert, a diabetic, brought the civil suit in 2010. His complaint contends that “deliberate indifference” about inmates’ medical care violates Eighth Amendment prohibitions against cruel and unusual punishment.

Plaintiffs argued that part of the blame lies with Wexford Health Services, Inc., one of the defendants. Illinois in 2011 awarded it a ten-year, $1.3 billion contract to provide health care to Illinois’ inmates, Wexford’s website says.

The complaint says Illinois pays Wexford a per-prisoner fee and “thus has an economic incentive to provide minimal care.” Wexford has denied that in earlier filings. A message left at its Pittsburgh, Pennsylvania, headquarters late Tuesday wasn’t immediately returned.

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