When Vivian Kneller was an infant, her pediatrician told her parents that they needed to take her from their home in Knoxville, Tennessee, to an eye specialist in Nashville. That doctor told them to seek treatment for Vivian at Wills Eye Hospital and the Children's Hospital of Philadelphia, where she was diagnosed with bilateral retinoblastoma, a rare form of childhood cancer.
After Vivian, now 1, was diagnosed, Tim and Alexis Kneller, knowing that retinoblastoma is a genetic disease, worried their son, Thomas, now 2, also might have the disease. Wills specialists diagnosed Thomas with bilateral retinoblastoma, as well.
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"When we got that confirmation, it was just like being punched in the stomach and then being kicked in the stomach," Tim Kneller said. "It's not one, but both of our children now going through this. There were some really dark times."
With two sick children needing care in a city far from home, the Knellers realized they would have to quit their jobs to move to Philadelphia temporarily – to save their children's sight and potentially their lives.
"It became apparent within the first three weeks that we weren't going to be able to work, if we were going to make this work without stressing one or the other one of us out to the breaking point," Kneller said.
Retinoblastoma is a childhood cancer caused by malignant cells in the retina that grow into a tumor or multiple tumors. The disease can lead to blindness if not diagnosed and treated early, and in the worst cases it can lead to death. Of the 200 to 300 children diagnosed with retinoblastoma each year, 1 in 4 have it in both eyes, a condition known as bilateral retinoblastoma.
Retinoblastoma used to be treated by eye removal or external beam radiation, which can cause other forms of cancer. But in 1994, Wills and the Children's Hospital of Philadelphia became one of four centers in the world to help develop and use a specific form of chemotherapy to treat the disease.
"Over the past 30 years, we have made enormous headway in the management of retinoblastoma," said Dr. Carol Shields, director of ocular oncology at Wills Eye Hospital, where both Vivian and Thomas have been receiving treatment. "Fifty percent of eyes used to be removed. Now it's down to 5% of eyes."
Now, systemic chemotherapy involving two or three drugs administered intravenously over a specified period is usually the first step in treating retinoblastoma. If that protocol is not enough to thwart the cancer, a process called intra-arterial chemotherapy, during which chemo is injected directly into the ophthalmic artery, may be used. In an even newer approach, called intravitreal chemotherapy, a tiny needle is used to inject a chemo drug into a specific part of the eye.
The development of advanced chemotherapy treatments "was a complete paradigm shift in how we viewed retinoblastoma," Shields said.
Retinoblastoma can come from DNA changes passed from parents to children, but advances have been made using in vitro fertilization and genetic testing so that parents who have the disease are able to go through medical procedures to help prevent it from spreading to the next generation."Thomas was only 2 years old when we met him," Shields said. "By the time he's 30 years old, thinking of having his family, we have a way that we can engineer the genetic mutation out of his family tree so that when he goes to have his kids, his kids will not likely have this mutation, so his kids will not likely have retinoblastoma."
Six cycles of systemic chemotherapy shrank a tumor blocking the vision in Thomas's right eye enough so that he now can see out of it, and the three small tumors in his left eye also have greatly diminished.
"This young boy is going to live a normal life, and he's going to have normal vision," Shields said, adding that Thomas is likely to get full vision back in both eyes.
Vivian also has responded well to treatment, and both children will continue to be monitored at Wills in the coming months and years.
Tim Kneller said his children are "doing phenomenally. … Children are so resilient. I don't want to make it sound like a rose garden. Obviously, it's been hard, but at the same time, we feel absolutely blessed to be in America and to be in Philadelphia while they're undergoing treatment."
Now, the Knellers are heading back to Knoxville.
A high school English teacher, Alexis Kneller will stay home for now to take care of Thomas and Vivian. Tim Kneller, a third-generation chimney sweep, shut down his small business when the family moved to Philadelphia. He is trying to start that back up.
"We've gotten used to hearing from other parents, 'I can't imagine,'" Kneller said. "But as a father, and I feel like I speak for my wife, as well, as a mother, as a parent, there's nothing you wouldn't do for your children, and that helps you get over the seemingly impossible obstacles."