Thailand star swimmer who won Asian medal with bone cancer withdraws from SEA Games for surgery

By Trung Thu December 10, 2025 | 02:56 pm PT

Thai star swimmer Kamonluck Tungnapakorn, also known as Kaopoon, has been forced to withdraw from the 33rd SEA Games just days before her scheduled events, following the need for surgery due to her worsened bone cancer.

The Thailand Swimming Association confirmed that the 20-year-old requires immediate surgery. Despite her withdrawal, the association announced that Kaopoon will retain her status as a national team athlete at this SEA Games, meaning she will receive full benefits and financial support for her medical treatment, according to Thairath.

A quiet battle

Kaopoon’s ordeal began in late July when she experienced swelling and pain in her jaw, which she initially mistook for a wisdom tooth issue. However, a biopsy following an X-ray revealed a malignant bone tumor, a rare form of cancer.

Facing a diagnosis that required intensive weekly hospital visits, Kaopoon attempted to balance her treatment with her final semester of university and her athletic career. Determined not to give up, she asked her doctors if she could continue training for the SEA Games and the Asian Championships in India.

Thai swimmer Kamonluck Tungnapakorn (L) is pictured with her father shortly after being hospitalized for bone cancer treatment in August 2025. Photo by Facebook/MrMooke Mooke

Kaopoon's doctors, prioritizing her health but acknowledging her determination, allowed her to compete conditionally based on her response to the first round of chemotherapy in September. Kaopoon responded well enough to compete at the Asian Championships in October, where she helped Thailand win a bronze medal in the women's 4x100 m freestyle relay.

She competed under strict medical instructions from the doctor, administering her own white blood cell-stimulating injections for six days and wearing a wig as her hair began to fall out.

Kaopoon underwent endoscopic surgery to remove the tumor in late October. However, her condition deteriorated rapidly in late November. Her cheekbone swelled, she experienced eye irritation, and she lost the ability to chew solid food or fully open her mouth.

MRI results revealed the tumor was spreading aggressively under her left eye. Doctors ordered an immediate halt to all training and scheduled urgent surgery, just five days before the SEA Games swimming event was set to begin.

Kamonluck Tungnapakorn after chemotherapy and surgery in late November 2025. Photo by Facebook/MrMooke Mooke

The decision to withdraw from SEA Games 33 was made in consultation with her club, doctors and Thailand Swimming Association.

"We sincerely apologize to the Swimming Association of Thailand, Bangkok Elite Swim Team, and all of Khaopun’s fans," her father wrote on Facebook. "We never intended to conceal anything but have been coordinating closely with the hospital doctors and the team’s medical staff throughout. Only in the past 2-3 days did her hospital doctor inform us that Khaopun must stop training and undergo immediate surgery to treat her condition before it worsens."

Kaopoon had been set to compete in the 4x100 m freestyle relay and the 50 m butterfly.

The swimming event at the SEA Games 33 runs from Dec. 10 to 15 at the Aquatic Palace in the Huamark Sports Complex, Bangkok. Thailand fields the largest team with 26 athletes, followed by Malaysia (23), Indonesia (22), Singapore (21), Vietnam (16), Philippines (11), Laos (10), Myanmar (9), Brunei (4) and Timor Leste (2).