Doctors and state officials who tried to get chemotherapy for a Utah boy diagnosed with cancer five years ago were trying to save his life, their lawyers told a federal judge.

The defendants are asking U.S. District Judge Ted Stewart in Salt Lake City to throw out the lawsuit filed by the boy's parents, who insist he never had a rare form of cancer and is doing fine.

The state eventually abandoned the fight for chemotherapy, but charged Daren and Barbara Jensen with kidnapping and medical neglect when they took their son Parker in 2003 to Idaho in defiance of a custody order. The parents settled the Utah charges by pleading guilty to misdemeanor custodial interference. Those convictions were later expunged from the record.

The Jensens are suing two physicians, formerly at the University of Utah; a former chief of the Utah Division of Child and Family Services; a DCFS social worker and an assistant Utah attorney general for instigating the custody order in Juvenile Court.

The state officials are being sued in their personal, but not official, capacity; another federal judge excused the state as a defendant in 2006.

"Time is of the essence with this disease," Andrew Morse, an attorney for physicians Lars Wagner and Karen Albritton, told Stewart on Thursday.

The family's attorney, Karra Porter, said genetic testing would have shown Parker, of Sandy, did not have Ewing's sarcoma, a rare and aggressive cancer, when a pea-sized growth was removed from under his tongue. Experts say if it was cancer, the disease could reappear.

Porter alleged the doctors refused to commission a genetic test because it would have diverted Parker Jensen from a clinical study.

The parents filed the lawsuit in 2005, claiming the defendants violated their parental and constitutional rights.

The 17-year-old boy will be a senior at Jordan High School this fall.

Stewart didn't immediately rule on the defendants' request to quash the lawsuit.