Therapy involves injection as part of liver treatment, not drinking liquid

A test of a cancer therapy by Chinese researchers based on baking soda - or sodium bicarbonate - shows promise but is still in the preliminary stages of research, and much more testing is needed, they said.

The researchers made the statement after heated discussion arose online about the research, with some netizens speculating that drinking sodium bicarbonate dissolved in water can cure cancer.

The study, published in the journal eLife in August, was led by Hu Xun, a cancer researcher at the Second Affiliated Hospital of Zhejiang University's School of Medicine, and Chao Ming, a radiology researcher at the hospital. All 40 liver cancer patients on whom the therapy was tried during the trial responded positively.

An infusion of soda before a procedure to restrict a tumor's blood supply appeared to aid the attack on cancerous cells.

The research aroused public attention over the past few days, with many netizens excited because they believed doctors had found an effective and cheap way - merely a drink of soda water - to cure liver cancer, one of the most common types of cancer among Chinese people.

"The research is valid, but it is preliminary," Chao said in a statement posted on the hospital's website on Monday. "Repeated tests are needed."

The therapy involves injecting sodium bicarbonate into the blood vessels that supply tumors. Patients are not asked to drink it, he said, adding that it is not clear that slightly alkaline water, such as soda water, is beneficial to the treatment of cancer.

In addition, the therapy only proved effective in patients with liver cancer in the research. Further research is needed to see whether it is effective against other cancers, he said.

Zhang Yuewei, a radiologist at Beijing Tsinghua Changgung Hospital who had discussed the research earlier with Chao, said the new therapy is at an early research stage, and the therapy is intended to improve the effectiveness of the usual treatment for liver cancer, not to replace it.