Medicinal mushrooms in cancer treatment

A Cochrane review in 2016 looked at reishi mushrooms as a cancer treatment. These are also called Ganoderma lucidum or G.lucidum. The review included 5 ​randomised trials.​

They found that when G.lucidum was given with standard treatment there was a small benefit. The standard treatment was chemotherapy and radiotherapy. It led to an increase in the activity of immune cells. G.lucidum seemed to be well tolerated when given with conventional cancer treatment. 

But the authors state that the trials had limitations. They say we need more trials of better quality. They conclude there is not enough evidence to say reishi mushrooms can be used as a cancer treatment.

Shiitake mushrooms are native to East Asia. They are grown worldwide for their supposed health benefits. They are valued in some cultures as an anti cancer agent.

The fresh and dried forms of the mushroom are commonly used in East Asian cooking. There are herbal medicines that use:

• extracts from the mushroom

• sometimes the whole dried mushroom

One shiitake extract called lentinan is a beta glucan. This is a type of complex sugar compound.

Beta glucan may stimulate the immune system. It may do this by triggering certain cells and proteins in the body to attack cancer cells. In laboratory studies, it seems to slow the growth of some cancer cells.

In China a literature review of 12 studies looked at lentinan. They looked at studies where people had it with chemotherapy for lung cancer. They found that lentinan worked on the immune system. It also improved quality of life in lung cancer patients. 

We need larger scale studies before we will know how shiitake extracts can help people with cancer.

Maitake mushrooms are used in Japan and China to treat diabetes and hypertension. They contain a complex sugar called beta-glucan.

Studies in the laboratory have shown that maitake extract can:

• stimulate the immune system

• lower blood sugar levels 

There is no evidence from clinical trials that maitake extracts can cure cancer.

A Brazilian study looked at Agaricus sylvaticus mushrooms. People taking part had the mushroom as part of their diet after bowel cancer surgery. 

It found that people who had the mushrooms had a better quality of life. This was compared to people who didn't have the mushrooms.

The benefits included:

• more ability to do physical exercise

• less feeling sick

• better mood

• fewer aches and pains

• better sleep

• better appetite

• less abdominal pain, especially after eating

• fewer bowel problems such as constipation, diarrhoea, and wind

Used for centuries in Eastern Ancient medicine, this extract is believed to refresh bodies and extend life.

Phellinus linteus is known as song gen in Chinese medicine, sang-hwang in Korean and meshimakobu in Japanese.

Researchers have looked at these extracts in the laboratory. This lab research showed that this type of mushroom extract may slow the growth of breast cancer cells. It has also been shown to have anti cancer effects on skin, lung and prostate cancer cells. 

We have to be cautious about such early research. Substances that can kill cells in laboratory conditions don't necessarily turn out to be useful treatments in people.