Last week, a Chinese Foreign Ministry spokesman denied making any deal for Wang's release, but he did not rule out the possibility of parole.
Chinese law has clear rules on the release or medical parole of criminals.
In a letter to the U.N. Human Rights Commission, the parents said they asked authorities to arrange a brain scan for Wang because he suffers from headaches and his eyesight is failing, according to the group Human Rights in China. His parents fear Wang may have a brain tumor. Wang's parents also have written to China's Justice Ministry, Wang's prison in northeast China and even Chinese President Jiang Zemin, but their son has not been examined and treated, the New York-based group said. Human Rights in China said it translated Wang's parents' letter into English and sent it to the U.N. commission. Copies also were being sent to U.S. President Bill Clinton and British Prime Minister Tony Blair, who both plan to visit China this year.