Moss performed the 13 1/2-hour operation on March 8 along with Oscar Salvatierra, MD, professor of surgery and pediatrics and the hospital's director of pediatric kidney transplantation.

Brandon Pride, shown with parents Keira and David, is ready to go home after a week of recovery from a nearly 14-hour surgery. Without the rare operation, he would have needed dialysis and a new kidney.

The patient, Brandon Pride, was well enough to run the halls of the hospital after just a week, and returned to his home in Gilroy with his parents, Keira and David Pride. They credit their doctors with Brandon's amazing recovery. "The best thing about this unfortunate stuff is that this is a really good hospital. We couldn't ask for better doctors. I'm just glad we live so close," said David Pride.

The Prides and physicians also give credit to Brandon. "He's been great. He hasn't lost a single pound or his hair through the chemo," said Keira Pride. She added that throughout his treatment Brandon has remained energetic, playing with his favorite trains, trucks and the family dog. "He's a strong kid," she said.

The successful surgery and treatment means Brandon should continue to live a normal life and is unlikely to undergo dialysis or organ transplantation. The Prides are both being tested as potential organ donors for Brandon, just in case. But "there's an excellent chance he's been cured of his cancer," Moss said.

Last November, David Pride noticed a small lump below Brandon's rib cage while changing his diaper. Within weeks, Brandon was diagnosed with Wilms' tumor, the most common type of solid tumor found in children. About 350 cases of Wilms' tumor occur in the United States annually.

In only 3 percent of cases (including Brandon's) both kidneys are affected. Tumors found in the second kidney are usually small and located in either the upper or lower lobe and easily removed, leaving enough of the organ to function normally. The kidneys act as filters for the body, removing toxic waste that is concentrated and excreted in the urine. Without at least one kidney or artificial cleansing through dialysis, a person cannot survive.

In Brandon's case, not only were both kidneys diseased, but the tumor in the less-affected kidney was located in critical areas: where the kidney is attached to the heart via an artery and a vein, and to the bladder via the ureter. The standard of care for a child in Brandon's condition at any other hospital most likely would have been to remove both kidneys.

By the time of Brandon's most recent surgery, he had already undergone two operations. In December, biopsies of both kidneys were taken. In February, his doctors removed the right kidney. But the latest procedure was the longest and most complicated. It involved a 12-person team, including surgeons, radiologists, pathologists, anesthesiologists and others.

During surgery, Brandon's remaining kidney, which is about the size of a teabag, was removed. Over a six-hour period, the cancerous tissue on the tiny organ was cut out, and the partial kidney was then treated with radiation while it lay in a preservative ice bath. Finally, it was re-implanted and reconnected inside Brandon's body.

Having the kidney outside the body allowed the surgeons to more precisely remove cancerous tissue. The radiation oncologist could also target only the edges of tissue that had been in contact with the tumor, avoiding potential radiation damage to healthy tissue.

Salvatierra performed a similar operation a dozen years ago. He said the earlier patient continues to thrive, and there's every reason to predict a similar optimistic outcome for Brandon. "We removed 60 percent of the kidney. The portion of the kidney we were able to save is providing Brandon almost the same level of function as he had before the procedure," Salvatierra explained.

Salvatierra also said this treatment would not have been possible without the expertise and coordinated collaboration of Packard Children's Hospital's specialists.