Surgeons at Massachusetts General Hospital in Boston performed the first penis transplant in the US earlier this month, The New York Times reports. The groundbreaking procedure, underwent by a 64-year-old patient whose penis was removed because of cancer, could be used to help injured veterans, cancer patients, and accident victims.

If everything goes well, the recipient, a bank courier named Thomas Manning, will be able to urinate normally within a few weeks and regain sexual functions within weeks to months. The penis for the transplant came from a deceased donor.

"We’re cautiously optimistic," Curtis L. Cetrulo, a plastic and reconstructive surgeon who led the operation told The New York Times. "It’s uncharted waters for us."

The 15-hour surgery, which cost between $50,000 to $75,000 and was paid for by the hospital, wasn't the first penis transplant in the world. In 2006, doctors in China successfully performed the procedure on a 44-year-old patient who had lost his organ in an accident. But two weeks after the surgery, the patient requested the penis to be removed, saying he and his wife were suffering from psychological problems.

In 2014, a transplant was performed in South Africa on a 21-year-old who had lost his penis after a circumcision procedure gone wrong. Six months after the surgery, the recipient's partner was pregnant. Surgeons at Johns Hopkins University School of Medicine are also planning on performing a penis transplant on a veteran who was injured in a bomb blast in Afghanistan.

In the US, the procedure is being considered especially for military veterans, who often suffer pelvic injuries, with damages to genitals and urinary tracts. Between 2001 and 2013, more than 1,300 men in the US military have suffered injuries to their genitals in Iraq or Afghanistan, according to the Department of Defense Trauma Registry.

The Massachusetts General Hospital surgeons operated on five or six deceased patients to prepare for the penis transplant, dissecting the organs and analyzing the anatomy. For now, they say they will consider new patients on a case-by-case basis, reserving the operation for cancer and trauma patients, not transgender people.

Manning, the patient in this month's transplant, was left with a one-inch stump after his own penis was removed because of an aggressive and sometimes fatal type of penile cancer. Penile cancer is rare, with about 2,000 new cases a year in the US, according to the American Cancer Society.

Manning decided to go public about the surgery to fight against the stigma associated with that type of cancer. He says he hopes to go back to having a love life again after the operation. "If I’m lucky, I get 75 percent of what I used to be," he told The New York Times. "Before the surgery I was 10 percent. But they made no promises. That was part of the deal."