Survivor Stories
June 23, 2026 • 4 Min
Back to previous page

Diet, Exercise, and a Clean Lifestyle

Mark Olsen

pancreatic cancer survivor Mark Olsen surrounded by his family--a young man in a brown shirt and jeans, a young woman in a white shirt and jeans, an older man in a dark zip pullover and dark jeans, an older woman in a tan sweater and jeans, a young man in an open button down shirt with a t shirt under and tan pants, and a young woman in a white sweater and jeans
  • 20 years of stomach pain eventually led to diagnosis
  • Softball-sized tumor
  • Microsatellite instability informs treatment
  • Chemotherapy plus immunotherapy

For at least twenty years, my stomach was bloated and irritated. 

Eating just about any kind of food gave me diarrhea, pain, and cramps. My doctors tested me for everything—IBS, Crohn’s disease, etc. All they came up with was that I was intolerant of certain foods.

Softball-Sized Tumor

By 2021, I was in so much misery that I needed more answers. My doctor ordered an ultrasound, which showed I had a fatty liver. I tried eating an ultra-clean diet, but it didn’t really help. In November 2022, I began to have bloating, back pain, and considerable stomach pain. My wife coerced me to go to the ER and the doctor there ordered an ultrasound and a CT scan. The outcome? Stage III pancreatic adenocarcinoma. 

My tumor was large: 9 x 6 cm, which is roughly the size of a softball. Unfortunately, I was not eligible for surgery due to portal vein involvement.

MSI-High Genetic Mutation

Within a month I had started my twelve rounds of FOLFIRNOX treatment at Corewell Health in Troy, Michigan under the care of Dr. Adil Akhtar.  Once it was confirmed it was not surgical, we sought out second opinions from University of Michigan, Henry Ford Health, and the Mayo Clinic.

Dr. Philip Philip at Henry Ford discovered that I have an MSI-High genetic mutation. which means it has a high number of mutations. Studies have shown that these types of tumors respond well to immunotherapy.  Dr Philip prescribed me a two-year course of Keytruda (pembrolizumab), an immunotherapy treatment. I also began a strict diet, exercise, and a clean lifestyle. 

Help me find a pancreatic cancer expert near me.

Learn more

 The Mayo Clinic also discovered that I had blockage of the portal vein, and I had to spend a week in Minnesota and have a stent put in through the kidney to get to the vein.  This saved my life as it was completely blocked and miraculously, my body created small blood veins to keep my lower intestines alive and if those ruptured, I would have died within minutes.

The chemotherapy was rough, the hardest thing I ever experienced. Itwas even rougher during the weeks they added immunotherapy. I experienced a lot of neuropathy but managed to finish all twelve rounds. 

Feeling Fantastic!

Today I am feeling fantastic! It has been three-and-a-half years since I finished the chemo and two years since I finished Keytruda. My most recent PET scan showed zero cancer activity, and the CT was stable and remained the same as it has been for two years. There is a small mass still, but the doctor thinks it may be scar-tissue.

My CA 19-9 levels are holding at 6.8 and CEA at 0.9. I feel great with this excellent response for almost three-and-a-half years since diagnosis! 

That tumor is now about the size of a shriveled ping pong ball, with no activity in more than three years.

Full of Energy

The crazy part is now that I have been treated for pancreatic cancer, my stomach issues are gone, and I feel better than ever. Yes, I am eating an ultra-clean, basically whole-foods-only diet and zero seed oils, basically only food from God. Some of my docs say that I might have had this tumor growing slowly for years, or maybe it was chronic pancreatitis, but others aren’t sure. I am full of energy!

I’d like to tell other people who have been diagnosed with pancreatic cancer not to give up hope, and to fight, fight, fight. Everyone is their own story, that is the most important thing to remember and learn! Do not get your information from a Google search; get your information from trusted sources. Be persistent with diet and exercise routines as well as lifestyle changes and for all the men out there, listen to your wives when she tells you to go to the doctors!