The diagnosis was skin cancer, and the grapefruit-sized tumor on the back of the head had to come off. But when the patient is 13 feet tall, perhaps half of that being neck, the surgery is complicated.

So it was yesterday morning at the National Zoo, where a crew of 28 -- keepers, veterinarians, a surgeon from Children's Hospital and the animal park's director -- pitched in for the elaborately choreographed operation on Jafari the giraffe. The surgery took less than an hour, and the animal was walking by noon.

Unfortunately, said chief veterinarian Suzan Murray, "we were only able to remove 90 percent of the tumor" because it had invaded the animal's bone. Chemotherapy may be an option, but she is not optimistic. Still, she said, this is the first time such a procedure has been performed on a giraffe, and scientists can learn from it.

"Even though the prognosis is poor," she said, "he's paving the way for management of giraffes in zoos."

Jafari, who weighs more than 1,300 pounds and will be 3 years old in December, came to the zoo last year. A month ago, keepers noticed a lump behind his left ear. He is trained to stand still for minor medical tests, so they drew some fluid. Monday's biopsy results confirmed that he had a tumor.

The young giraffe had basal cell carcinoma, which is the most common skin cancer in humans but which has never been reported in a giraffe. Many people get it from sun exposure, but zoo staff members think that is unlikely in this case. On Tuesday, they decided to operate.

Zoo officials announced a briefing, a change from the past, when announcements were made after the fact. "We're going to do everything we can to keep people informed and operate the zoo in as transparent a fashion as we can," said the zoo's new director, John Berry, a former Interior Department official and conservation foundation executive who began work full time this month.

Keepers removed Jafari's food so his stomach would be empty while he was under anesthesia. He had not been eating much anyway.

The surgical team assembled at 7 a.m. in the Elephant House, which was closed to the public. They spent three hours rehearsing. Berry described what followed as "nothing less than a ballet."

The riskiest part of giraffe surgery is the anesthesia: It is hard to control such a big animal. If its long neck is in the wrong position during surgery, it can't breathe. The animal could have a deadly fall while going under or coming out of the anesthesia. Giraffes sometimes vomit under anesthesia, which can be fatal. A giraffe died at the zoo of anesthesia complications in 1998.

Veterinarians Mitchell Bush, of the zoo's Conservation and Research Center in Front Royal, Va., and Scott Citino, from the White Oak Conservation Center in Florida, gave Jafari the injection and held his head so he could breathe.

As the giraffe went under, the surgical crew positioned him on the padded floor of the Elephant House, with his head and neck on a padded ladder set atop hay bales. Two keepers massaged his neck muscles to prevent dangerous kinking. An oxygen tube was put down his throat.

Murray and Children's Hospital surgeon Kurt Newman used a scalpel and electric current to remove the tissue and cauterize the wound. The animal was resting on a tarp, and it took 10 or 15 people -- nobody could recall how many -- to drag him to his outdoor yard for recovery. "Many hands make light work," Berry joked.

After the anesthesia reversal drug was administered, Jafari quickly got up on his knees. After 15 minutes -- "the longest 15 minutes I've had, holding my breath," Berry said -- he stood up to his full height. He is receiving anti-inflammatory drugs for pain and an antibiotic to prevent infection. He had a limited meal yesterday, but Tony Barthel, an assistant curator, said he should be back on full rations today.

In about a week, he and the zoo's other male Rothschild's giraffe, Randall, will be back together. Yesterday, they sniffed at each other a few times across the fence that separated them in the yard.

"He's looking pretty bright," Barthel said, "like his normal self."

Jafari, right, a giraffe at the National Zoo, is reunited with Randall after undergoing surgery. Veterinarians were able to remove 90 percent of a tumor from Jafari's head in a procedure that required 28 people to perform. Stitches from the surgery can be seen around Jafari's ear.