Mr./Ms. Y, who was diagnosed with appendiceal cancer, underwent Gut Microbiota Transplantation and is now receiving Keytruda (an immune checkpoint inhibitor) every six weeks.
After receiving Gut Microbiota Transplantation (FMT), Y’s tumor markers have remained stable, and the chronic constipation that had persisted for years has been resolved.
“I hope to suppress the cancer through a powerful combination: Keytruda, which strips the tumor’s armor, and gut bacteria that enhance the body’s immune attack,” says Y.
We interviewed Y about their condition after FMT, current dietary habits, and outlook for the future.
Profile
Diagnosis: Appendiceal cancer
Transplantation Period: November 6, 2024 – January 14, 2025
Number of Transplants: 6-session course
Transplanting Medical Institution: Tanaka Clinic, Jinzenkai Medical Corporation
Interviews
What were the results of the contrast-enhanced CT scan after the Gut Microbiota Transplantation?
Y: I was relieved when my primary doctor told me that there were no signs of tumor progression. He said, “You’re holding steady.” I’m scheduled to receive another dose of Keytruda (an immune checkpoint inhibitor) in six weeks, and I truly feel that the current treatment is effectively keeping the cancer under control.
So far, I haven’t experienced any side effects from Keytruda, even after six months of treatment. However, my doctor warned me not to let my guard down, saying, “Some patients suddenly develop side effects even a year later.”
Since this is an immunotherapy, not a traditional chemotherapy, there is also a possibility that the immune response could become overactive.
Can you tell us what led you to try FMT and how your primary doctor responded to it?
Y: I was already familiar with Gut Microbiota Transplantation because I had attended academic conferences on the topic. After my surgery, when I was about to begin immunotherapy, I was advised to consider combining it with FMT, which led me to visit Tanaka Clinic.
Since immunotherapy was scheduled to start soon, we decided to begin the transplantation even before receiving the results of the pre-FMT intestinal flora balance test.
After receiving FMT at Tanaka Clinic, I underwent an intestinal flora balance test, which showed that the balance of gut bacteria was shifting in a positive direction.
When I brought my pre-FMT test results to my primary doctor in Osaka, I was pleasantly surprised to find that he was already familiar with gut microbiota transplantation. It seems to be a topic of growing interest among medical professionals.
He told me, “There’s still limited data available as a medical treatment, so we can’t say for sure it will lead to good results. But it’s okay for you to go ahead with FMT.”
Later, after the FMT, he said, “It’s possible that the cancer is being suppressed as a result of the FMT as well.”
How did you feel about Dr. Tanaka, the doctor in charge of the FMT?
Y: Dr. Tanaka was easy to talk to and had a cheerful, friendly demeanor. Regarding my diet, he kindly acknowledged that “eating out frequently is understandable due to your work.”
When I have the option to choose my meals, I try to avoid wheat.
How has your constipation, which had been a concern, improved?
Y: My constipation has improved significantly. I used to have hard stools that were difficult to pass, but now I’m able to have normal bowel movements. I see this improvement as a good sign.
After completing FMT, I continued drinking NanoGAS® hydrogen water, and I believe that also contributed to relieving my constipation. I’ve even recommended it to people I work with.
As I started talking more openly about having cancer and struggling with constipation, I was surprised to learn that many men also suffer from constipation.
Is there anything in particular you pay attention to in your diet or daily lifestyle?
Y: At first, I submitted a record of my meals through the digital diary. Since then, I’ve mostly cut out foods containing wheat, such as bread, ramen, and udon. I still crave sweets from time to time, but I try to avoid refined sugar. I never really drank milk to begin with, and as for dairy products, I only occasionally eat yogurt.
What are your future treatment plans, and when might additional FMT sessions be considered?
Y: I have completed one course of FMT (six sessions), and Dr. Tanaka told me that we’ll observe my condition for about three months and, if necessary, consider adding single additional sessions. I’m continuing with Keytruda at a doubled dose every six weeks. Since I have a predisposition to diabetes, I’m also monitoring my blood sugar levels. For now, I’m aiming to maintain my current condition until the next CT scan.
What Y continues to do to maintain a healthy gut environment
- Has mostly eliminated wheat-containing foods such as bread, ramen, and udon.
- Avoids drinking milk.
- Continuing to drink NanoGAS® hydrogen water
Finally.
A clinical study combining immune checkpoint inhibitors and FMT began in the summer of 2024, targeting patients with esophageal and stomach cancers.
The treatment that Mr./Ms. Y received was a combination therapy using the NanoGAS®-FMT method.
Y shared that “the tumor has not grown and my condition has remained stable” and expressed that they “feel a synergistic effect from the two treatments.”
This observation has been positively evaluated not only by Dr. Tanaka, the physician in charge of the transplant, but also by Y’s primary care doctor, who noted that “FMT may be contributing to the treatment response.”
This case is expected to offer a promising lead toward new treatment options for cancer.
For more information on the potential of FMT for cancer patients, Dr. Tanaka, the representative director of the Association for Clinical Research of Fecal Microbiota Transplantation Japan, provides a detailed explanation on YouTube. We encourage anyone interested to check it out.
Thank you very much, Mr./Ms. Y, for sharing your valuable story.
Fecal Transplant Channel: Interview with Dr. Tanaka (Part 1)
Fecal Transplant Channel: Interview with Dr. Tanaka (Part 2)
Please note: This article is based solely on Mr./Ms. Y’s personal experience. Treatment effects may vary from person to person, and similar results are not guaranteed. Please consult a medical specialist for specific treatment decisions.
