A mutated gene. A rare hereditary disease. A Philly-area teen battles three cancers at once

Rylee Monahan has golf in her DNA — a passion she got from her father, who went to college on a golf scholarship. The 14-year-old easily made the junior varsity team at Pope John Paul II High School in Royersford, where she’s a freshman.

But along with her athletic prowess, Rylee also inherited a rare and deadly disease that predisposes her to cancer at an early age. Her father, Ryan Monahan, has battled four types of cancer since boyhood. He passed the genetic mutation on to both Rylee and her 17-year-old sister, Madison.

Rylee was 9 when doctors diagnosed her with brain cancer. Since then, she’s developed two other types of cancer and endured three brain surgeries, two skull surgeries to treat bone cancer, and dozens of rounds of radiation and chemotherapy.

In August, just before Rylee’s 14th birthday, doctors found what they suspect is cancer in her right ovary and right lung.

So far, Madison is in the clear, though her chances of getting cancer by age 40 are near 100%.

“It kind of feels like you’re a time bomb,” said Madison, who turns 18 next month.

It can feel scary, she said, but watching her sister — and also her father — confront multiple cancers over the years has honed yet another family trait: an indomitable spirit.

On Sept. 24, the Monahans, who live in Gilbertsville, Montgomery County, will participate in the 2023 Parkway Run & Walk, organized annually by the Children’s Hospital of Philadelphia on the Benjamin Franklin Parkway, to raise money for pediatric cancer research. CHOP named Rylee an “ambassador.” Her team, “Rock Star Rylee: One Step Closer,” already has raised more than $22,000 in donations.

» READ MORE: A medical mystery: Why two Philly-area cousins, just miles apart, got rare brain cancers

Madison, Rylee and their father all have Li-Fraumeni syndrome, which is caused by a mutation in a gene that normally works to prevent cancer. There is no cure.

But Ryan Monahan likens childhood cancer research to “shots on goal.” The more shots you take at a hockey or soccer net, the more likely you’ll score a goal.

Just as his mother did for him as a boy, Ryan Monahan is pushing doctors to use experimental treatment to save Rylee’s life. He urges them to treat his daughter like the case study for their next big medical advance.

“Rylee’s probability of surviving is very, very low,” he said. “Our objective is to keep her alive and healthy until there is a breakthrough.”

At 45, Ryan Monahan is living proof that playing long odds can pay off. He was an 11-year-old sixth grader who loved soccer when doctors diagnosed him with bone cancer, or osteosarcoma, on his right femur.

Doctors told his mother that there was a 75% chance he would die within two years.

The only option doctors could offer was to amputate his leg. They told his mother to enjoy what little time she had left with him.

Kathleen Monahan refused to accept his grim prognosis.

She found a Philadelphia surgeon, Richard Lackman, at Thomas Jefferson University Hospital, who was one of the few doctors in the nation performing limb-salvage surgery. He used cadaver bone, screws and metal plates. It was a pioneering approach back then.

“It won’t be as good as the leg God gave you. But you’ll still have a leg,” his mother recalled Lackman telling him.

It would mean no more running and jumping. No soccer. So Lackman suggested swimming — or golf.

After recovering from 10 hours of surgery and 22 treatments of six chemo drugs over 18 months, Ryan was taken to a golf course for the first time by an orthopedic doctor. He was a natural.

“It ended up being a lifeline for Ryan,” said Kathleen Monahan, 69, who repeatedly told him: “Never let cancer define you.”

Ryan Monahan fell in love with his now-wife Crystal at the University of Mount Olive in North Carolina, where she had a volleyball scholarship and he got a full ride for golf.

The Monahans married in 2002. Ryan Monahan had no idea that he carried a mutated tumor-suppressor gene, and that there was a 50% chance that their children would inherit it.

“I always give her a hard time, like she didn’t read the fine print,” he joked.

Six years after they married, a dermatologist caught a melanoma behind his right ear during a routine cancer screening.

Then, in 2012, he was diagnosed with an aggressive, soft-tissue leiomyosarcoma on his left forearm.

“I’m either the unluckiest person in the world, or something is going on,” he remembered telling his childhood surgeon, Lackman, then at MD Anderson Cancer Center at Cooper in Camden.

By then, Lackman had replaced Monahan’s cadaver bone with a metal prosthesis, fitted from hip to knee. The doctor suggested that Monahan and his girls go for cancer predisposition testing. At the time, genetic screening was not widely adopted.

Monahan and his wife weighed the pros and cons. “Why would you want to know that?” some friends asked them.

But whenever the girls got a headache, sniffle or low-grade fever, Crystal Monahan went into a panic: Was it cancer?

“You can’t live your life like that. You would drive yourself crazy,” she said.

Pediatrician Garrett Brodeur, who runs CHOP’s Cancer Predisposition Program, said the idea is to get out ahead of any cancer. If diagnosed with a genetic predisposition, the girls would be eligible for surveillance testing to catch cancer early.

“Some people describe having a predisposition to sort of a Damocles sword. There’s a sword hanging over your head, held by a thread or a rope, and you never know when, or if, it’s going to fall,” Brodeur said. But the upside, he said, is being able to detect and treat a “grape-sized tumor” before it “becomes a grapefruit.”

Roughly 1 in 10,000 people has Li-Fraumeni syndrome and doctors have seen an increase in cases in recent years, mostly because oncologists are more aware of it and more likely to suggest genetic testing, Brodeur said.

Madison was 7 and Rylee was 4 when their parents took them to CHOP to get blood drawn.

Six agonizing weeks later, Crystal and Ryan Monahan sat across from a doctor and a geneticist at CHOP.

The doctor started the conversation with, “Unfortunately …”

Crystal Monahan’s heart dropped. Later, the couple sat for a long time in their car in CHOP’s parking garage, trying not to cry with Madison and Rylee in the backseat.

“We didn’t want them to live in fear all the time,” Ryan Monahan said.

Most kids go for annual physicals before the start of each school year. Rylee and Madison, along with their father, go for full-body MRIs at least once a year.

Years went by and the girls showed no signs of cancer.

In December 2018, Ryan Monahan was diagnosed with stage 4 lung cancer.

Four months later, in April 2019, Rylee’s MRI scan showed a “barely visible” brain tumor in her left-frontal lobe. She underwent a 13-hour brain surgery, followed by 33 rounds of proton radiation treatment.

Since then, the tumor has twice grown back, requiring two more brain surgeries.

Last October, during Cancer Awareness Month, Madison’s high school volleyball team hosted a “Panthers vs. Cancer” event in which players with loved ones diagnosed with cancer walked them across the court before the game.

» READ MORE: "After a double mastectomy, a Franklin High baseball coach wants everyone to know: Men get breast cancer, too.

Rylee wanted her hair in a ponytail. As her mom brushed her hair up, her hand felt a bump in the back of Rylee’s skull.

The cancer had struck again, this time osteosarcoma, or bone cancer.

“It was like a gut punch,” Crystal Monahan said.

Rylee had the first of two skull surgeries just before Halloween last year.

The following month, in November 2022, Rylee was well enough to watch her sister’s team win a volleyball state championship title. (Like her mom, Madison earned a volleyball scholarship and has committed to play for William and Mary in fall 2024, although she’s just starting her senior year in high school.)

By Christmas, Rylee’s brain tumor resurfaced on the right-frontal lobe. Rylee dreamed of seeing Hawaii. The family quickly organized a trip.

Over the summer, the family visited SeaWorld Orlando, Ocean City, N.J., and Hersheypark.

On Aug. 25, Rylee had a biopsy of her ovary. Doctors believe she now has ovarian cancer.

Two days later, she joined her dad on the golf course.

Ryan Monahan, now cancer-free thanks to a relatively new immunotherapy treatment, said the family is determined to “live life the best you can in between the cancer.”

Some days, Crystal Monahan, a kindergarten teacher’s aide, has to hide the Li-Fraumeni syndrome Facebook group from her feed. Other days, she feels strong enough to scroll through posts and offer encouragement.

“Cancer already takes enough from you,” she said. “You can’t let it take away your joy. You can’t let it steal every piece of happiness.”

Ryan Monahan, who works in marketing in Merck’s oncology division, sometimes feels guilt for having passed on Li-Fraumeni syndrome to his girls.

But his own experience offers perspective. If doctors had not amputated his leg, he wouldn’t have gotten a golf scholarship. He never would have met his wife. He wouldn’t have passed on his “crappy genetic code.”

But he also wouldn’t have two extraordinary kids, he said.

“Madison is a better athlete and a smarter kid than either of us ever were, and Rylee, to me as a parent, is just the nicest human being,” he said. “They’re both off the charts.”

Crystal Monahan said she can’t imagine a life without Ryan and her girls.

“My worst fear is losing them,” she said.