By D'Vera Cohn
Washington Post Staff Writer
Friday, April 4 1997; Page C01
The Washington Post
Hsing-Hsing, the National Zoo's giant panda, has cancer in his right testicle and will undergo surgery to remove it, zoo officials said yesterday.
There are no signs the disease has spread, but that cannot be confirmed until the April 23, 1997 operation, according to the zoo's chief veterinarian, Richard Cambre.
The 26-year-old panda and his mate, Ling-Ling, were given to the National Zoo by the Chinese government in 1972 and quickly became its most popular attraction. Giant pandas are an endangered species; there are fewer than two dozen outside China, including only three in the United States.
Despite multiple matings and five births, the National Zoo's pair never produced a cub that lived longer than a few days. Ling-Ling died in 1992.
The zoo has scheduled a celebration April 16 to mark the 25th anniversary of the pandas' arrival. A symposium on panda research is also planned.
Hsing-Hsing's cancer was discovered Wednesday during a physical examination, under anesthesia, that was scheduled because his keepers had noticed several problems. The panda's testicle appeared swollen, he had lost weight and he limped on his left leg. Laboratory tests confirmed the cancer yesterday.
The black and white bear weighs 240 pounds, down from 280 in his prime. He has arthritis, which accounts for the lameness. But aside from that and the cancer, he generally is a healthy old animal, said Cambre, who added that the panda does not appear to be in pain.
The surgery, again under a general anesthetic, will take "a couple of hours," Cambre said. The operation will be done by Cambre and Lucy Spelman, the zoo's associate veterinarian. While Hsing-Hsing is on the table, they will take tissue samples from the left testicle and adjoining lymph nodes to test for cancer. If it has spread, Cambre said, the only option would be to remove both testicles. Radiation or drug therapy is not practical for a panda.
"If [the lymph nodes] tell us it has spread, there is not a whole lot we can do in an animal 26 years old and technically at the end of his life span," Cambre said.
But there are some hopeful signs the disease can be contained, he said. X-rays taken Wednesday did not show nodules on the bear's internal organs that could indicate cancer. The testicle has been swollen only since February, so "it does not appear that [the cancer] is really aggressive," he said.
Hsing-Hsing was not examined sooner because veterinarians were not sure at first that the swollen testicle was a problem, Cambre said. Male panda testicles often enlarge during breeding season in response to rising hormone levels.
The surgery will not be performed right away because of the risk of putting the animal under general anesthesia again and because "pathologists do not believe there is any need to rush right back in and get it immediately," Cambre said.
Hsing-Hsing is "beyond prime breeding age," Cambre said, so the operation won't have a major impact on his reproductive ability. There will not be a long recovery period after surgery, and Hsing-Hsing may not be out of public view for more than a few hours. "These animals are amazing," he said. "They don't lie around. I don't foresee any long recovery where he is off exhibit at all."