St. Francis Hospital and Medical Center has agreed to pay the federal government $516,527 to resolve a complaint that it overbilled Medicare for the costs of administering a prostate cancer treatment. The U.S. Department of Health and Human Services charged that the hospital was aware that its billing errors had resulted in overpayment by Medicare, but failed to immediately report the errors or repay the excess Medicare reimbursements. A hospital spokeswoman said the overbilling was the result of "a misinterpretation of billing requirements" and was unintentional. She said the hospital settled to avoid litigation costs. The Connecticut U.S. Attorney's Office, which announced the settlement, said it involved the treatment of hospital patients with Lupron, which is administered by injection to treat prostate cancer in men and endometriosis and fibroids in women.