
Landmark surgery restores normal urination to cancer survivor after seven years; UCLA-led team plans more procedures in clinical trial
In a monumental leap forward for transplant medicine, a team of American surgeons has successfully performed the world’s first human bladder transplant, restoring normal urinary function to a cancer survivor who had lived without it for seven years. The groundbreaking procedure, conducted at Ronald Reagan UCLA Medical Center on May 4, 2025, could offer a transformative new path for millions suffering from bladder impairment.
A first-of-its-kind operation
The recipient, 41-year-old Oscar Larrainzar — a father of four — had lost both kidneys and most of his bladder to cancer and had been dependent on dialysis ever since. In a complex eight-hour surgery, Larrainzar received a kidney and bladder from a single deceased donor. The surgical team was led by Dr. Nima Nassiri of UCLA and Dr. Inderbir Gill of USC, combining expertise in urology and transplant science.
Almost immediately after the procedure, the new kidney began producing urine, and Larrainzar was able to urinate naturally — something he hadn’t done in nearly a decade. The kidney function stabilized quickly, ending his need for dialysis.
“This first attempt at bladder transplantation has been over four years in the making,” said Dr. Nassiri. “For the appropriately selected patient, it is exciting to be able to offer a new potential option.”
A culmination of years of research
The transplant marks a major milestone not only for the patient but also for UCLA’s medical research. “Bladder transplantation has been Dr. Nassiri’s principal academic focus since we recruited him to the UCLA faculty several years ago,” said Dr. Mark Litwin, chair of UCLA Urology. “It is incredibly gratifying to see him take this work from the laboratory to human patients at UCLA, which operates the busiest and most successful solid-organ transplant program in the western United States.”
The surgical team trained extensively for the operation, practicing on cadavers with the aid of robotic systems. This meticulous preparation culminated in Larrainzar’s historic surgery, the first of five planned for a clinical trial that could reshape the standard of care for patients with severe bladder damage.
A game-changing alternative to risky reconstruction
Until now, treatment options for bladder impairment have been severely limited. Surgeons have often resorted to reconstructing bladders using sections of a patient’s intestine — a technique associated with significant complications. The advent of bladder transplantation opens up a path toward restoring normal function with fewer associated risks.
Patients who undergo this transplant, however, will require lifelong immunosuppressive therapy to prevent organ rejection. The success of the upcoming trial surgeries will determine whether larger-scale trials can proceed — and whether this procedure will become part of routine medical practice.
A new frontier in transplant medicine
Oscar Larrainzar’s recovery is being closely watched by the global medical community. If his progress holds, the surgery may represent a revolutionary shift in the treatment of urological disorders and cancer-related organ loss.
From dialysis-dependent to fully functional, Larrainzar’s journey is nothing short of historic — and a beacon of hope for patients around the world.



