When gut flora from obese donors helps terminally ill cancer patients

The gut flora of overweight or obese patients may partly explain their weight gain. Could it allow terminally ill cancer patients to gain back lost weight? This is what a team of researchers set out to discover.

Created 29 September 2021
Updated 14 May 2024

About this article

Created 29 September 2021
Updated 14 May 2024

Cachexia brings forward images of weakened hunger strikers or patients in their last days of life. It is a state of extreme fatigue and emaciation and a sign of severe malnutrition or the terminal phase of certain diseases, such as gastroesophageal cancer. It is well known that gut microbiota seems to play a crucial role in the regulation of appetite, which cancer patients lack. This gave these researchers an idea, namely to implant their patients with gut flora from healthy obese donors since some of these (sidenote: Microorganisms Living organisms that are too small to be seen with the naked eye. They include bacteria, viruses, fungi, archaea and protozoa, and are commonly referred to as “microbes”. What is microbiology? Microbiology Society. ) may have played a role in their weight gain.

No improvement in appetite but beneficial effect on cancer progression

Twenty-four cachectic patients with inoperable gastroesophageal cancer who were to receive palliative chemotherapy participated in the study. Twelve received flora from a healthy overweight or obese donor while the other twelve received their own microbiota (control group). No one knew who was receiving what so as not to influence the outcome. Contrary to the expectations of the researchers, allogenic FMT from a healthy obese donor did not improve the recipient's satiety or cachexia before chemotherapy. It nevertheless seems to have had a beneficial effect on the progression of the disease. Compared to the control group (which received its own flora), the cancer was better controlled in the 12 patients who received microbiota from an obese donor. Their survival was also improved. 

Gut bacteria and the effectiveness of chemotherapy? 

An analysis of their new fecal microbiota confirmed that the gut flora transplant was successful despite the chemotherapy that followed. However, it is impossible for the researchers to know at this stage whether certain specific gut bacterial species could lead to more effective chemotherapy treatment. Studies on a larger scale will be needed to find out more. While waiting for the next findings, follow the news of the Institute but do not under any circumstances try to make a home-made gut flora cocktail!


De Clercq NC, van den Ende T, Prodan A et al. Fecal Microbiota Transplantation from Overweight or Obese Donors in Cachectic Patients with Advanced Gastroesophageal Cancer: A Randomized, Double-blind, Placebo-Controlled, Phase II Study.  Clin Cancer Res. 2021 Apr 21.