Matthew S. Swope Sr., his dad, said doctors said if Matthew survives the disease for five years he has as pretty good chance for a normal life.
Matthew's disease is at a "stage four" level, the most dangerous, his mother said.
His mother gives him Interferon shots three times a week. An active child, he slows down after the shots and sleeps more, she said.
"He gets tired easy," his father said. "If he's up and moving around much, he plays out pretty quick."
Matthew has been into Hot Wheels since he was 2, Brandy said.
"Whenever we went to Wal-Mart, he had to have one," she said. "He could always tell the difference between Hot Wheels and other brands."
Matthew said his favorite is an orange "General Lee" of the "Dukes of Hazard" television show popular in the 1980s.
"It's a collectible. You can't play with it," he said.
The idea of collecting Hot Wheels for Matthew surfaced in December when his aunt, Peggy Swope, asked what he wanted for Christmas. He said 1 million hot wheels.
Members of the Swope's church, Sideling Hill Christian Church, learned of Matthew's request and word went out.
Brandy said Fulton County Commissioner Bonnie Mellott Keefer joined the effort by setting up Hot Wheels collection boxes around the area, mostly in churches.
"On Christmas Eve she went to five different counties, Fulton, Franklin, Bedford, Huntingdon and Washington counties collecting the boxes. She picked up about 10,000 cars," Brandy said.
Keefer could not be reached for comment.
"Other people started to collect them, too," Brandy said. "This thing has really ballooned. I don't know where we're going to store them all." The Swopes grew up in Berkeley Springs, W.Va. They've been married nearly eight years and also have a daughter, Harlie, 7.
The house they live in once belonged to Matthew Swope Sr.'s grandparents. The couple works at his uncle's dairy farm about two miles away.
Hot Wheels, which costs around $1 each when new, can go up in value over the years as they become collectible.
Many of the cars being sent to the Swopes come from members of a Hot Wheels collectors' club who learned of Matthew's wish, his mother said.
Many of the cars from club members come in complete boxes that one day will be collectible if left intact, his father said.
Club members pledged to send Matthew a box of new cars every year until he reaches 18, his father said.
"One box of cars that really touched me was sent by a 6-year-old boy in Waterfall who wanted Matthew to have his Hot Wheels," Brandy said.
Waterfall is in northern Fulton County.