The disturbing physical symptoms cropped up a few weeks before Mike Shelly's freshman year at Marple Newtown.
"I was experiencing ankle pain, stomach aches, and throwing up," he said. "And finally, one night, the stomach pain was unbearable and I had to go to the hospital."
Shelly was first examined at Bryn Mawr Hospital and then steered to Nemours/Alfred I. duPont Hospital for Children in Wilmington.
The 14-year-old was diagnosed with stage IV Burkitt lymphoma, a high-grade B-cell non-Hodgkin's lymphoma. The rare and aggressive form of cancer causes the cells in a person's lymphatic system to abnormally reproduce.
"I was kind of in shock," said Shelly, a junior offensive lineman for Marple Newtown's successful football squad. "You hear about other kids getting cancer, but you never think it's going to happen to you."
Doctors at duPont performed surgery to remove the tumor that was pushing up against Shelly's colon. That was followed by 10 grueling rounds of chemotherapy.
Strong support, naturally, came from his parents, Mike and Melissa, sister Amanda, 24, and brother Andrew, 20.
It also came from Marple Newtown's tight-knit student body and community. About a month after the surgery, Smith, in a wheelchair, attended a home game and led his teammates onto the field.
"There was a sea of orange-colored "#ShellyStrong" T-shirts," Mike Shelly, 17, recalled. "It was a pretty emotional night."
Shelly, of Newtown Square, underwent physical therapy after his final round of chemotherapy. He became stronger each day with light running, cycling, and squats.
The 5-foot-10, 250-pounder was back playing football, mostly with the JV team, as a sophomore. "He practiced and played sparingly," Marple Newtown coach Chris Gicking said. "He had to gradually work his way back from cancer and the follow-up treatment."
Now, Shelly is the starting center for a squad that is one of the top contenders in the PIAA District 1 Class 5A playoffs. The No. 3-seeded Tigers (10-1) easily downed No. 14 Upper Moreland, 35-7, in first-round action Friday night.
Shelly is one of two Marple Newtown players to overcome cancer. Cameron Mathes, a senior wide receiver and cornerback, was diagnosed with leukemia when he was only 11/2 years old.
"Just being a cancer survivor, you have a certain bond with someone who has experienced the same thing," Mathes said. "So when this happened to Mike, I, like everyone else, wanted to do all I could to help."
The Tigers have thrived under the direction of quarterback Anthony Paoletti. The junior has passed for a single-season school record of 2,356 yards and 23 touchdowns. "He's one of the hardest working kids I know," Shelly said.
Marple Newtown hosts No. 11 seed West Chester East (5-6) in a district quarterfinal at 7 p.m. Friday.