When first-time parents Brianna and Adam Nuñez left their local hospital in New Jersey with their newborn son, Mateo, in August 2021, they prepared for everything. The car seat was secured, the nursery was ready, and they were already well-stocked with diapers.

But nothing prepared them for what would happen just a few weeks later. While Brianna had some complications at the end of her pregnancy, Mateo seemed like a perfectly healthy baby boy when he was born. Soon after coming home, they noticed he was wheezing and looked exhausted. “He could never sleep on his back and when we changed him, he would cry and turn purple,” says Brianna.

Their pediatrician first thought it was RSV, but medications to treat the virus didn’t help. Mateo’s condition continued to worsen and at 11 weeks old, he turned blue in Brianna’s arms. “He stopped breathing, and I called 911,” she says. “I didn’t think he was going to make it. That’s when our whole life turned upside down.”

A Tiny Newborn with a Massive Tumor

In the local emergency department, an X-ray followed by a CT scan revealed that Mateo had a tumor on the left side of his chest measuring 8-by-8 centimeters, about the size of a large orange. Because the tumor was so large, it was compressing his heart, left lung, and airway, and it encased several large blood vessels in his neck and chest.

Doctors later confirmed Mateo had neuroblastoma, a rare childhood cancer that starts in immature nerve cells called neuroblasts. There are about 800 newly diagnosed cases of neuroblastoma every year, but the location of Mateo’s tumor was rare — only about 15% of cases occur in the chest. “When we heard that Mateo had a large tumor, we just broke down and cried,” says Brianna. “We didn’t think it was real. We didn’t think this was our life.”

Mateo was immediately sedated and intubated to help him breathe. After nearly two weeks in the pediatric intensive care unit, he was not improving and had other complications, so the doctors transported him to NewYork-Presbyterian Morgan Stanley Children’s Hospital to see specialists in pediatric oncology.

In the middle of the night on November 16, 2021, Brianna rode in the ambulance with Mateo, with Adam following behind. Dr. Erica Fallon, the director of pediatric surgical oncology at the hospital, saw Mateo soon after he arrived. “He was really sick at that point,” she says. “If his breathing tube came out, the tumor would have compressed his trachea. He was so, so fragile.”

‘One of the Direst Cases We Have Seen’

In small babies like Mateo, the treatment for neuroblastoma can be immediate surgery, but because Mateo’s mass was so large and pushing against his heart and lungs, he first needed chemotherapy to shrink the tumor. “I’ve seen many neuroblastoma cases,” says Dr. Darrell Yamashiro, a pediatric oncologist and hematologist at NewYork-Presbyterian Morgan Stanley. “Mateo’s was one of the direst that we have seen.”

Dr. Yamashiro started Mateo on 12 rounds of chemotherapy, and he responded remarkably well. As the tumor shrunk, it slowly relieved pressure on Mateo’s airway and after almost 80 days of being intubated, the doctors were able to remove his breathing tube. The following week, Mateo was strong enough to go home and continue with outpatient treatment. After several months, the tumor shrunk by 50%, at which point the doctors decided Mateo was ready for surgery.

“They told us it would be a marathon and not a race,” says Brianna. “You have to take it one day at a time. In our situation, it was sometimes one hour at a time, and sometimes one minute at a time. We’re just very thankful for NewYork-Presbyterian. I really truly believe we wouldn’t be here if it wasn’t for Dr. Yamashiro, Dr. Fallon, and the amazing nurses who became our friends.”

A Challenging Operation

Because of the location and size of the tumor, Mateo’s surgery was especially difficult. Dr. Fallon opened the breastbone (or sternum) to access the tumor in the chest cavity. When they opened Mateo’s chest, Dr. Fallon and her team found the mass was stuck to everything around it and encasing several important arteries and nerves. “Through careful and meticulous dissection, we separated the tumor from the chest wall, the lung, the lining of the heart, and blood vessels,” she says.

Part of the tumor also extended into the left neck, so Dr. Fallon had a pediatric radiologist come to the operating room to perform an ultrasound to look for any residual tumor, and none was found. Mateo’s only complication was a treatable condition called Horner Syndrome, which affects the nerves in his left eye and face. “We removed the entire tumor from the chest and neck in one piece,” she says. “We were ecstatic speaking with the family afterwards. This came after months of chemotherapy, time, patience, and hard work.”

The surgery lasted about six hours, and when it was over, Dr. Yamashiro visited the family to celebrate, too. “He was so excited, he was saying, ‘Yes, yes, we did it!’” says Adam. “We had a group hug. To just know the struggle, the battle that it was, it was so awesome to be able to share that moment with Dr. Yamashiro.”

“Mateo is a remarkable little boy,” says Dr. Yamashiro. “It took an entire village at NewYork-Presbyterian to take care of Mateo, and I feel confident that he is actually cured of his neuroblastoma.”

Living a ‘Miracle’ Every Day

Mateo was declared cancer-free on November 8, 2022. On his birthday every year, Brianna and Adam take the day off work and bring Mateo to the family’s favorite beach in Ocean Grove, New Jersey. This year, Mateo jumped in the ocean for the first time.

Now 3 years old, Mateo loves Sesame Street, trucks, basketball, helping with yard work, and baking cookies with Brianna, who works as a professional chef. He’s obsessed with Christmas, and Brianna and Adam are grateful to be home celebrating together as a family. They remember Mateo’s first Christmas at the hospital, when the nurses bought Mateo a tiny Santa outfit.

“Sometimes I catch myself looking at him when he is playing and have flashbacks,” says Adam. “We were in the worst place of our lives when we heard Mateo had cancer. We didn’t think we were going to have these moments with him. So now it’s like we’re all healing from seeing him grow. We still get emotional sometimes, and I think that’ll never end.”

Every day, Brianna wears a beaded bracelet with the words “Miracle Mateo.” The nickname was given to Mateo by Adam’s brother and immediately caught on with family members and friends. “We call him Miracle Mateo because he is truly a miracle, and the bracelet reminds me to have hope,” she says. “If you don’t believe in miracles, I say look at my son.”