BEIJING – With the world’s largest cancer epidemic, China has been one of the most rapidly expanding markets for oncologic drugs for years. Now, an alternative approach is growing about twice as fast: traditional Chinese medicines.

Sales of traditional cancer treatments, often containing ingredients as unlikely as toad skin and turtle shell, surged 35 percent to almost 17 billion yuan ($2.7 billion) last year, market researcher Sinohealth Intelligence estimates.

China’s overall cancer drug market of 65 billion yuan grows at a compounded annual rate of 17 percent, estimated Citigroup analyst Richard Yeh.

One medicine alone, Shenqi Fuzheng Injection, used to fight tumors and improve chemotherapy tolerance, generated 1.3 billion yuan in 2014 for Livzon Pharmaceutical Group Inc.

With a new cancer case every 10 seconds and more than 2,000 years of experience with traditional remedies, China is spearheading an integrative approach that even the largest U.S. cancer centers are embracing. Last week, Chinese researchers showed Shenqi Fuzheng improved the efficacy and reduced the toxic side effects of radiation therapy in lung-cancer patients.

“Chinese medicine serves more often as an adjuvant therapy,” said Teo Eng Kiat, a cancer specialist and president of Singapore Chinese Physicians’ Association. “Our practices show it can help patients finish chemotherapy or the radiation process more smoothly.”

While relatively few randomized, controlled clinical trials have assessed the efficacy and safety of traditional Chinese medicines, researchers outside China are eager to test them.

The U.S. National Cancer Institute has funded numerous studies to explore the anti-cancer potential of traditional Chinese medicine, from natural ingredients to acupuncture and Qigong, a wellness approach that combines elements of movement, meditation and martial arts.

University of Texas MD Anderson Cancer Center researchers in Houston showed in June that a hot water extract from the skin glands of a type of toad used to treat solid tumors in China fought non-Hodgkin’s lymphoma in lab experiments.

Yung-Chi Cheng, a professor of pharmacology at Yale School of Medicine in New Haven, Connecticut, is investigating a Chinese herbal formulation, known as PHY906, in patients after an early-stage clinical study published in March found it enhanced the anti-tumor activity of Bayer AG’s cancer drug Nexavar.

The investigational drug combines a number of botanical ingredients with a broad medicinal effect, rather than a single molecule used to target a specific action, Cheng said.

“Using one chemical to treat a complicated disease — I think it may be asking too much,” he said.

Kanglaite, made from the seeds of a tropical Asian grass called Coix, has been used to treat more than 2 million cancer patients in China since the mid-1990s. It brought in about 1.5 billion yuan last year for Zhejiang Kanglaite Pharmaceutical Co., its closely held manufacturer, which aims to complete late- stage trials in the U.S.