番茄社区

A year and a half after his surgery, a penis and scrotum transplant recipient has nearly full functionality, his Johns Hopkins transplant team reported in a .

"He can urinate, gets erections, and has recovered sensation," lead surgeon Richard Redett, MD, director of the genitourinary transplant program and interim director of plastic and reconstructive surgery at Johns Hopkins in Baltimore, told 番茄社区. "I think this is a game changer" for functional penis transplant.

Although it's the fifth penis transplant in the world, it's the most extensive because the others didn't include the scrotum or abdominal wall tissue, Redett said.

The patient, a veteran who was injured by a roadside bomb in the Middle East, was first referred to Hopkins to discuss conventional reconstruction, which involves taking a flap from another part of the body and "fashioning it into something that looks like a penis."

The team at Hopkins has been doing complex penile reconstruction in wounded soldiers and in children with birth defects for many years, but conventional reconstruction doesn't usually restore full function.

"We get something that looks pretty realistic" and patients frequently report a return of sensation, Redett said, but it's challenging to reconstruct a urethra, for instance, because they tend to get strictures or fistulas and patients may have problems urinating. And the flap, usually taken from the forearm, isn't made from inherently erectile tissue so patients have to get an implant that doesn't always stay in place.

The transplant patient wasn't a candidate for reconstruction because injuries to his extremities left him without enough tissue to make a flap, Redett said. Both legs had been amputated above the knee, and there was substantial tissue loss in the lower abdominal wall.

So Redett and his team enlisted the help of an organ procurement organization, the Living Legacy Foundation, to identify a potential donor -- a search that took about 15 months.

In the meantime, the team practiced on cadavers. They learned precisely how much tissue they'd need for a successful transplant, but they faced questions about how to perfuse it properly. Since the patient was missing the dorsal penile and cavernosal arteries, the surgical team had to use deep inferior epigastric arteries to revascularize the graft.

Generously, the donating family -- whose terminally ill son was on life support -- had allowed the team to inject tracers and see blood flow in real time prior to attempting the transplant.

"We'd figured it out on a cadaver, but it's a big leap to do it in a patient," Redett said. "We injected the dyes, imaged it, and the entire graft lit up, so we knew we could do this safely."

The procedure took a total of 14 hours, about 5 of which involved procuring the graft. Much of the rest of the time was spent connecting small blood vessels and nerves and attaching the urethra. The transplant recipient had about 1.5 cm of remnant penile tissue with the urethra, and when the graft was harvested, extra lengths of urethra, blood vessels, and nerves were also taken.

After the surgery, getting the immunosuppression right is critical, Redett said. He and his team developed a novel bone marrow infusion protocol that they delivered two weeks after the transplant. Essentially, they take bone marrow from the donor, process it, and give it to the graft recipient.

This approach has allowed the Hopkins transplant team to get many transplants, including hand transplants, down to a single low-dose immunosuppression regimen, Redett said. The veteran had alemtuzumab and glucocorticoid induction therapy, followed by the bone marrow infusion and tacrolimus maintenance monotherapy.

Now, , the patient has mostly normal function, Redett said. He won't be able to father children since the testicles weren't transplanted. But he's returned to school full time, lives independently using leg prostheses, and reports improved self-image and high satisfaction with the transplant, the team wrote in NEJM.

Those outcomes are an improvement over at least two of the earlier penis transplants. The first, , failed, and the second, , became infected and some of the tissue had to be removed.

Massachusetts General Hospital did , in an older patient with better but still suboptimal outcomes. "He's voiding well but may have limitations with the ability to get and sustain an erection," Redett said.

Details of haven't yet been reported in the literature.

Redett noted that the Hopkins transplant involved some 30 people, from the organ procurement organization to the other doctors, nurses, surgical techs, and engineers who each played a key role in the transplant. (The NEJM letter listed 24 authors.)

Paying for the procedure was "complicated," Redett said, with the hospital picking up the cost, though "that's not sustainable long-term." Since it's a "life-enhancing" but not a "life-saving" procedure, payers haven't been convinced that they should cover the transplant. But Redett said teams are working to show that this is "a superior reconstruction over conventional techniques."

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