Twice a month, our journalist answers readers’ questions about health and well-being.
Recently, my brother learned that the colorectal cancer he was diagnosed with last year was having a local recurrence. What can he do, concretely, to help with his remission? Foods to eat or avoid? Furthermore, is it possible to undergo immunotherapy treatment?
Anonymous
Our reader’s question is specific to his brother’s experience, but this quest for concrete solutions after a cancer diagnosis is universal. To answer this, we brought together two surgeons who are interested in these questions: Dr.D Carole Richard and the Dr Roy Hajjar.
“This kind of question makes the patient a little more proactive, and we like proactivity,” says the D straight away.D Carole Richard, head of the digestive surgery department at the CHUM.
PHOTO PROVIDED BY THE CHUM
The DD Carole Richard
First thing, she says, exercise. European studies have shown that patients who do cardiovascular exercise at least 30 minutes a day, four or five times a week, generally respond better to oncology treatments. “But we must especially not make patients who do not have the strength to do it feel guilty,” emphasizes the D.D Richard. Second point, avoid smoking, and third point, maintain a healthy weight, to better tolerate treatments.
Which brings us to the last point: diet.
In colorectal oncology, we monitor patients’ vitamin D levels, and we advise limiting intake of red meat and processed meat. The rest of the recommendations are general: a healthy diet, rich in fruits and vegetables, proteins and fiber, summarizes Carole Richard.
We would like to give a specific recipe to your reader’s brother, and tell him to eat this or that thing and not to eat this or that other thing. This would be our dream, but we do not have the evidence to provide such precise recommendations. Quietly, we work on it.
The DD Carole Richard, head of the digestive surgery department at the CHUM
“We are working hard on this, in Montreal, and we hope to have an answer one day,” adds the Dr Roy Hajjar, who will return to the CHUM after his subspecialty training in colorectal surgery.
Fiber and microbiome
Carole Richard, Roy Hajjar and their immunologist colleague Manuela Santos were interested in the protective role that dietary fiber could have in the cure of colorectal cancer and even, perhaps, in recurrence.
In populations that consume enough fiber, there are fewer cases of colorectal cancer. Studies have shown this. “But once cancer is diagnosed, will consuming fiber help? This was the subject of our research at the CHUM,” explains Roy Hajjar. Their goal? To determine whether consuming more fiber, on the one hand, could reduce postoperative complications and improve healing, and, on the other hand, have a beneficial effect on cancer and recurrence. Their results were published in scientific journals Gut And Clinical Cancer Research.
The microbiome, explains Roy Hajjar, would be at the heart of the mechanism.
PHOTO ERIC BOLTE, PROVIDED BY THE CHUM
The Dr Roy Hajjar
When bacteria ferment certain types of fiber, they will produce an anti-carcinogenic product in the intestine called butyrate. The other effect is that it consolidates the intestinal barrier, so it can increase the mucus layer and therefore promote faster healing.
The Dr Roy Hajjar
These effects have only been demonstrated in animal and cellular models, specifies Dr.r Roy Hajjar, and not in patients.
Current knowledge does not allow us to recommend certain types of fiber in particular. “For the moment, I will limit myself to saying to have a varied diet, according to the recommendations of 25 to 38 grams of fiber per day”, indicates the Dr Hajjar.
Warning: patients should not “stuff themselves with fiber”, advises the DD Carole Richard. Too much fiber could even be harmful, especially in patients who are already experiencing intestinal disturbances due to chemotherapy. “Moderation tastes better,” she reminds us.
Immunotherapy
Modification of the microbiome remains a booming avenue of research, for colorectal cancer, but also for other types of cancer, such as lung and melanoma. At the CHUM, a team launched a rather unusual clinical trial this year: patients suffering from melanoma will receive pills containing fecal microbiota from healthy donors, to see if this will allow them to better respond to immunotherapy treatments.
Our reader also wondered if his brother could follow immunotherapy treatments, these treatments which help the immune system to find and destroy cancer cells, and which have revolutionized the treatment of certain cancers.
Currently, only a “very small subset” of colorectal cancer patients respond well to immunotherapy, says Dr.D Richard.
In the near future, Roy Hajjar plans to explore the subject, comparing the microbiome of patients in this “subcategory” to the microbiome of other patients to find avenues that would maximize response to therapies.
“The dream would be that we could one day analyze someone’s microbiota, then advise them to modify this or that thing because they need this or that bacteria,” illustrates Carole Richard.
“We could say to this person: for you, this intervention will be beneficial, but for you, it is another intervention,” summarizes Roy Hajjar. The spectrum of current medicine is changing towards more personalized medicine… and it’s interesting! »