Radiation, electrical current and drugs may arrest the spread of cancer, but the body's immune system may actually be an effective weapon for defending itself.
In 2010, 26,390 people were diagnosed with cancer, according to the Hong Kong Cancer Registry. The disease killed 13,076 people that year. One in four men and one in five women under the age of 75 will develop some form of cancer.
Daniel Sze Man-yuen, associate professor at Polytechnic University's health technology and informatics department, has conducted research on immunology since 1994.
He spent more than seven years researching the immunomodulatory effects of Chinese herbal medicine.
One that grabbed his interest is the Coriolus versicolor mushroom, which is known as yunzhi in Hong Kong and the mainland.
Sze helped design and analyze data for a study published in March - which found that polysaccharopeptide, or PSP, a bioactive agent extracted from the mushroom, significantly increases the number of monocytes in human blood.
Monocytes are white blood cells that can become dendritic cells or macrophages, immune cells that identify and destroy foreign materials.
This means PSP from yunzhi may have the ability to strengthen the immune system and if a person has cancer, it helps defend against cancerous cells.
Sze says there is plenty of clinical evidence that yunzhi can be an effective type of cancer treatment, often used in conjunction with chemotherapy.
But there is less evidence for proactive immunomodulation, he says, because it is difficult to prove that someone has dodged cancer when there is no tumor to be seen.
"To prove whether yunzhi can prevent cancer would be a huge project," Sze says.
One advocate of proactive immunomodulation is Gregory Berry, an Australian Jungian psychotherapist and dream analyst, who has been running his own private practice in Sydney for three decades.
Berry, whose father died of skin cancer, says about 5 percent of his patients have cancer.
Listening to their experiences and analyzing their dreams, Berry was inspired to write the book China's Newest Anti-aging Secret.
In it, he claims that yunzhi, along with two other medicinal mushrooms - the ganoderma and cordyceps mushrooms - can prevent cancer and slow down the aging process.
Although Berry has not conducted research on the mushrooms himself and is not an oncologist, he thinks it is a shame that people only take the mushrooms after finding out they have cancer.
"Let's think about what part of the immune system can be rearmed and how we can rearm it," he says.
While waiting for more clinical evidence to back up Berry's claims, we could play it safe and consider taking medicinal mushrooms such as yunzhi after consulting a doctor.
