The digestive system of every person holds the key to cancer treatment, researchers claim. This is good news for cancer patients who are tired of therapies whose results are still unknown.

The usual therapies attack the cancerous cells in the bodies of patients, but new findings show that all this time, the body may have had the answer to this sickness, often referred to as the silent killer. The promising research results reveal that the microbiome found in the colon, which aids both the immune system in fighting infections and the digestive system in breaking down food, is highly beneficial in immunotherpaies in reducing the size of cancerous cells.

The study was conducted on cancer patients undergoing immunotherapy, wherein a person's immune system is strengthened so it can fight the dreaded disease. The study at the Gustave Roussy Cancer Campus in Paris, France, found that those who have taken antibiotics and had damaged the microbiome were likely to see tumors grow during therapies. Majority of the patients (69 percent) who had Akkermansia muciniphila, a kind of bacteria, had more chance of responding to immunotheraphy than those who did not possess the species. The group tested 249 lung or kidney cancer patients.

Another study, conducted at the University of Texas MD Anderson Cancer Center, found out that from the 112 patients with advanced melanoma, those who have rich and varying kinds of bacteria tend to be more responsive to immunotherapy than those who do not. Faecalibacterium and Clostridiales were believed to be advantageous, while the Bacteroidales was not beneficial for the treatment.

"It's really interesting and holds a lot of promise, we need to do more work but there are exciting glimmers here in treating some difficult diseases," the president of the Society for Applied Microbiology, Mark Fielder, said in an interview with BBC.