Integrative Oncology Approaches to Supporting Immune Checkpoint Inhibitor Treatment of Solid Tumours

Abstract

Purpose of Review

• Examine integrative oncology strategies supporting immune checkpoint inhibitor (ICI) treatment for adult solid tumours.

Recent Findings

• Beyond tumour-intrinsic factors, patient-associated factors (e.g., genetics, inflammation, diet) affect ICI response.
• Promising interventions:
  • Mediterranean-style diet with >20g fibre
  • Regular exercise
  • Live biotherapeutics
  • Minimize PPI/antibiotic use
  • Ensure vitamin D repletion
• Caution with cannabis use; VAE therapy appears safe.

Summary

• Investigate low-cost integrative strategies for better outcomes and fewer adverse effects.
• Research may lead to personalized care plans, nutrition, exercise, and inflammation modulation.
• Chronic stress affects ICI outcomes; mind-body approaches need further research.

Introduction

Immunotherapy and ICIs

• Immune system key to preventing tumour progression.
• Tumour evasion involves inhibitory molecules like immune checkpoints.
• ICIs (e.g., PD-1, PD-L1, CTLA4) aim to reverse tumour-induced immunosuppression.
• Effective for cancers like endometrial cancer, melanoma, RCC, NSCLC.
• Associated with immune-related adverse events (irAEs).

Response Variability

• Response to ICI varies by tumour type and patient population.
• Predictive markers include:
  • Tumour mutational burden
  • PD-L1 expression
  • Tumour-infiltrating lymphocytes
• External factors: genetics, inflammation, gut microbiota, diet.

Integrative Oncology

Whole Person Care

• Patient-centred, evidence-informed care combining conventional and complementary treatments.
• Focus on quality of life, resilience, and treatment outcome improvement.
• Core principles include individualised care and evidence-based medicine.

Strategies

• Nutrition, lifestyle, and natural products support a range of cancer treatments.
• Guidelines exist for integrative therapies in oncology (e.g., SIO-ASCO guidelines).

Systemic Biomarkers

Prehabilitation

• Prehabilitation improves surgical outcomes; applicable to systemic anticancer therapy.
• Chronic inflammation is associated with poorer ICI outcomes.
• Anti-inflammatory strategies: nutrition, exercise, reduced alcohol and smoking.
• Biomarkers like CRP, cytokines, and indices help assess inflammation status.

Physical Activity and ICIs

• Exercise improves quality of life, reduces fatigue and recurrence risk.
• Limited data on exercise and ICI treatment impact.
• Retrospective studies show active patients have better outcomes.

Role of Nutrition

• Nutrition is crucial in cancer care, influencing risk and outcomes.
• Key recommendations:
  • Early nutritional risk screening
  • Body composition and biomarker assessment
  • Multimodal interventions focusing on inflammation reduction

Dietary Patterns

• Mediterranean diet linked to better ICI outcomes in melanoma patients.
• Further research needed on diet impacts across different cancers.

Gut Microbiome and Supplementation

• Gut microbiome influences ICI response; modifiable via diet and supplements.
• Strategies include FMT, oral live biotherapeutics, and prebiotics.
• Conflicting evidence on probiotics.
• Postbiotics like SCFAs promote immune activation.

Nutritional Supplements

• Vitamin D has shown positive impacts on ICI efficacy.
• Lack of research on other supplements like omega-3.
• Mycotherapy shows promise in preclinical studies.

Caution with Cannabis

• Cannabis use linked to poorer ICI outcomes.
• Current data suggest avoiding cannabis during ICI treatment.

Chronic Stress and Mind-Body Therapies

• Chronic stress impacts tumour microenvironment and ICI efficacy.
• Mind-body therapies for stress management require further research.

Other Integrative Oncology Therapies

• VAE therapy shows no safety concerns when used with ICIs.
• Chinese herbal medicine is a promising area for supporting immunotherapy.

Conclusions

• ICIs are impactful but require integrative strategies to optimize outcomes.
• Investigate biomarkers and personalized treatment plans.
• Focus on diet, exercise, and inflammation modulation for better ICI support.
• Further research needed in integrative oncology approaches.