Sami Mansfield: ESMO 2026 and Lifestyle Medicine – Missing, or Opportunity?

In late October, oncologists, researchers and patient advocates from around the world gathered in Madrid for the ESMO Congress 2026. It is the annual meeting of the European Society for Medical Oncology, and one of the most influential stages in cancer care. The headlines were the ones we’ve come to expect: new antibody-drug conjugates, novel immunotherapy combinations, and survival readouts that will reshape treatment algorithms.

As a lifestyle medicine professional, I read a program like this with a second question running alongside the first. Not only what’s new in treatment, but where can lifestyle work with it. 

Exercise, nutrition, sleep and weight are not alternatives to standard of care. The question is whether they belong next to it.

Picture a man who finished his last cycle of FOLFOX in March. Stage III colon cancer, clear scans, a follow-up schedule taped to the fridge. At his first survivorship visit he asks what every survivor eventually asks: Is there anything I can do now, besides wait?

As I went through the ESMO 2026 program, I was looking for these answers. And while we didn’t see ballroom-scale presentations, it was there, just not always where oncology usually keeps its scorecard.

Oncology keeps score in survival

Overall survival, progression-free survival, disease-free survival. Those are the endpoints that earn a therapy a guideline slot and a line in the Presidential Symposium. If lifestyle medicine wants a seat at that table, it has to be judged on the same scorecard.

One lifestyle intervention already has been. In now well known CHALLENGE trial, 889 people with stage III or high-risk stage II colon cancer were randomized after adjuvant chemotherapy to a three-year structured exercise program or health-education materials alone. Five-year disease-free survival was 80.3% versus 73.9%. Eight-year overall survival was 90.3% versus 83.2%.¹

That 7.1-point absolute survival gain is the number to hold onto: it sits in the same range as therapies oncologists prescribe without a second thought. The cost was real but modest. Musculoskeletal adverse events ran 18.5% versus 11.5%.¹

ESMO responded. A February 2026 Clinical Practice Guideline update now recommends structured exercise programs for eligible patients with localized colon cancer, with an ESMO-MCBS score attached.² That is a lifestyle intervention entering a treatment algorithm. It happened once. The question for 2026 was whether it would happen again.

Where lifestyle showed up: the supportive-care lane

At ESMO 2026, lifestyle lived almost entirely in supportive care and symptom management. That’s valuable work. It is also a ceiling.

The clearest signal was a 50-minute special session, ‘What oncologists should know about non-pharmaceutical interventions.’ It packed exercise, nutrition and integrative oncology into three 15-minute talks. The exercise talk came from Christopher Booth, co-chair of CHALLENGE.³ The field’s one survival-grade lifestyle result got a quarter of an hour, in a lunchtime slot.

The abstracts followed the same pattern:

• FORX (LBA93). A weekly 30-plant diet during the first 12 weeks of immunotherapy. In 54 evaluable patients, fiber rose from 20.2 to 28.8 g/day, and 3.7% had grade 3 or worse immune-related toxicity.⁴ That proves the diet is doable on immunotherapy. It can’t show the diet lowered toxicity, because there was no control arm.
• Sleepio After Cancer (LBA91). In 308 women with cancer and insomnia, a six-week digital CBT program beat sleep-hygiene education. Insomnia remission at 24 weeks was 27% versus 12% by intention to treat, with gains in fatigue, depression, anxiety and hot flashes.⁵,⁶ Fewer than half finished the 24-week assessment (44% versus 34%), so the effect in real-world use is still an open question.⁶
• Nutrition care gaps (CN35). In a survey of 2,505 patients and survivors across 12 European countries, 20% had a nutritional assessment and 22% saw a dietitian.⁷ Nutrition is acknowledged and rarely delivered. The survey was funded by the medical nutrition industry.
• Prevention gaps (3884RO). In a lung-cancer prevention program, people with severe mental illness scored a median 3.0 out of 7 on WCRF adherence, against 3.5 for everyone else.⁸
  What I didn’t find: a single session in the online program on GLP-1 medications, semaglutide or tirzepatide. Weight appeared mainly as something cancer takes away, not something oncology helps manage.

The survival headline that isn’t lifestyle

The one nutrition-adjacent result with a survival number attached will travel fastest. Read it carefully.

EMT2 (LBA30) randomized 418 patients having liver resection for colorectal metastases to 4 g a day of EPA, an omega-3, or placebo.⁹ The primary endpoint, progression-free survival, was not met (HR 0.89; 95% CI, 0.70-1.13). Overall survival, a key secondary endpoint, favored EPA (HR 0.68; 95% CI, 0.48-0.96), with estimated five-year survival of 62.0% versus 45.1%.¹⁰

Three things belong next to that number:

• The primary endpoint failed. A survival gain without a progression gain needs explaining before it needs celebrating. The investigators themselves say it needs confirmation.¹⁰
• This is a prescription drug, not a diet. The intervention was high-purity icosapent ethyl.⁹ Nothing here tells a patient to eat more fish or buy a supplement.
• The placebo deserves a look. The comparator was mineral oil.¹¹ My inference, not the presenters’: in REDUCE-IT, the cardiovascular trial of the same drug, critics argued a mineral-oil placebo may have worsened the control arm.¹² EMT2 deserves the same scrutiny.

The drug’s manufacturer press-released the survival result the day it was presented.¹¹ The trial itself was investigator-led and sponsored by the University of Leeds.

The gauge trap

The most useful lifestyle-adjacent finding at ESMO 2026 was a warning.

A meta-analysis of 27 randomized trials (3086RO, n=4,213) asked what drugs for cancer cachexia actually deliver. Patients gained an average of 1.38 kg, and appetite improved. Quality of life, physical function and overall survival did not change. Adverse events rose (OR 1.51).¹³

In plain terms: the scale moved, and the patient didn’t. Body weight is a gauge, a readout. Function and survival are what a patient lives inside. When a field optimizes the readout, it can report success while the person in the chair is no stronger.

That lesson cuts both ways for lifestyle medicine. It argues against selling diets and exercise on weight or biomarkers alone. It also explains why CHALLENGE matters so much: it was measured on the outcome, not the gauge.¹

Missing, or opportunity?

Both. Supportive care helps patients cope. Oncology now has evidence that lifestyle can do more than that, and the 2026 program mostly didn’t follow it. Four places to start:

• Test lifestyle on oncology’s scorecard. FORX lists oncological response as a secondary endpoint.⁴ That is the right instinct. The next step is a randomized arm, powered for an outcome oncologists already trust.
• Build the delivery system CHALLENGE assumed. The trial delivered three years of behavioral support with supervised sessions.¹ Commentary on the trial has made the point bluntly: the benefit reaches patients only if infrastructure and insurance coverage expand to match.¹⁴ A guideline recommendation without a referral pathway is a sentence, not a service.
• Bring weight management into the room. Oncologists’ patients are starting GLP-1 medications now, with or without guidance on muscle, bone and exercise. ESMO 2026 had no session on it. That silence is a gap clinicians are filling alone.
• Measure thriving with the same rigor as survival. Sleepio shows what that can look like: a randomized trial of a deliverable, scalable tool, scored on outcomes patients feel.⁵,⁶ Function, fitness, sleep and the ability to complete treatment are endpoints. Score them as endpoints, not as gauges.

Not on the main stage is not the same as not important

Lifestyle medicine didn’t headline ESMO 2026. That tells us what made the Presidential Symposium. It doesn’t tell us what patients need.

Every survival gain announced in Madrid means more people living longer after a cancer diagnosis. That means more years in which fitness, sleep, nutrition and weight shape how those years feel. As treatment extends survival, the question shifts from how long to how well. That is where lifestyle medicine has evidence, deliverable tools, and a seat worth claiming.

The man at the start of this piece isn’t asking to cope better with waiting. He’s asking whether there is something to do. For colon cancer, oncology now has a randomized answer.¹ Best-in-class care means making sure that answer reaches him, alongside his treatment, and that the rest of the field asks the question with the same rigor.

What Else You Need to Know

Not that lifestyle improves survival in every cancer. CHALLENGE tested one intervention in one population: stage III and high-risk stage II colon cancer after chemotherapy.¹
Not that supportive-care research is second-tier. Sleep, symptoms and nutrition access matter to every patient in treatment.
Not that EPA, a 30-plant diet or GLP-1 medications should be started on the strength of ESMO 2026. None of these results supports that.
Not that lifestyle replaces treatment. CHALLENGE patients got exercise after standard surgery and chemotherapy.

References

1. Courneya KS, Vardy JL, O’Callaghan CJ, et al; CHALLENGE Investigators. Structured exercise after adjuvant chemotherapy for colon cancer. N Engl J Med. 2025;393(1):13-25.
2. Pentheroudakis G, Argilés G, Arnold D, Smyth E, Ducreux M; ESMO Guidelines Committee. ESMO Clinical Practice Guideline Express Update on the adoption of physical exercise in patients with localised colon cancer. ESMO Open. 2026;11(2):106019.
3. Booth CM, Kaasa S, Mao J. What oncologists should know about non-pharmaceutical interventions. Special session presented at: ESMO Congress 2026; October 23-27, 2026; Madrid, Spain.
4. Verhaert M, et al. Food intervention trial to reduce immunotherapy toxicity (FORX): impact of a weekly 30-plant diet on immune related adverse events. Presented at: ESMO Congress 2026; October 23-27, 2026; Madrid, Spain. Abstract LBA93.
5. Brennan DJ, et al. Digital cognitive behavioural therapy for insomnia in women with cancer: the Sleepio After Cancer (SAC) randomised controlled trial. Presented at: ESMO Congress 2026; October 23-27, 2026; Madrid, Spain. Abstract LBA91.
6. Friedman J. Digital app ‘immensely powerful’ in treating insomnia among women with cancer. Healio. October 28, 2026.
7. Ventura JJ, et al. Nutrition in cancer care: closing the gap between awareness and action. Presented at: ESMO Congress 2026; October 23-27, 2026; Madrid, Spain. Abstract CN35.
8. Abdayem P, et al. Lung cancer prevention in patients with severe mental illness: a real-world cohort experience from the INTERCEPTION-lung precision prevention program. Presented at: ESMO Congress 2026; October 23-27, 2026; Madrid, Spain. Abstract 3884RO.
9. Hull MA, et al. Omega-3 polyunsaturated fatty acid eicosapentaenoic acid (EPA) versus placebo after resection of colorectal cancer liver metastases (EMT2): a multicentre, double-blind, randomised phase 3 trial. Presented at: ESMO Congress 2026; October 23-27, 2026; Madrid, Spain. Abstract LBA30.
10. European Society for Medical Oncology. Phase 3 EMT2 trial demonstrates survival benefit for high-dose EPA. News-Medical. October 26, 2026.
11. Amarin Corporation. Amarin provides update on University of Leeds sponsored phase 3 EPA for Metastasis Trial 2 (EMT2) evaluating VAZKEPA/VASCEPA (icosapent ethyl) capsules on top of standard of care treatment in patients undergoing liver resection for colorectal cancer liver metastases (CRCLM). News release. GlobeNewswire. October 25, 2026.
12. Bhatt DL, Steg PG, Miller M, et al; REDUCE-IT Investigators. Cardiovascular risk reduction with icosapent ethyl for hypertriglyceridemia. N Engl J Med. 2019;380(1):11-22.
13. Yazji J, et al. Pharmacologic therapy for cancer cachexia improves appetite and weight but not survival or function: a meta-analysis. Presented at: ESMO Congress 2026; October 23-27, 2026; Madrid, Spain. Abstract 3086RO.
14. Exercise as medicine for preventing colon cancer recurrence. NEJM Journal Watch commentary, reproduced by Universimed.

by Sami Mansfield, Founder of Cancer Wellness for Life

Sami Mansfield, is the Founder of Cancer Wellness for Life and an exercise oncology and lifestyle medicine consultant. With over 20 years of experience in oncology wellness, she specializes in developing evidence-based exercise and lifestyle programmes for cancer patients and survivors. She is a contributing author to the American Society of Clinical Oncology (ASCO) guidelines on exercise, diet, and weight management during cancer treatment and serves as Chair of the Cancer Member Interest Group at the American College of Lifestyle Medicine.

You can also check out: 

ESMO 2026 Presidential Symposia: From Trial Results to Clinical Implications

Muna Al-Khaifi: Lifestyle Programs and Cardiometabolic Health in Cancer Survivors

Exercise as Part of Cancer Care: Lessons From the CHALLENGE Trial – Common Sense Oncology