# Advances in Functional and Metabolic Imaging for Early Tumor Treatment Response and Resistance Evaluation: A Review

## TL;DR

This review explores how advanced imaging techniques can detect early cancer treatment responses and resistance, aiming to improve personalized cancer care.

## Contribution

The paper provides a comprehensive synthesis of functional and metabolic imaging technologies for early tumor response and resistance evaluation.

## Key findings

- Functional and metabolic imaging outperforms traditional imaging in early tumor response assessment.
- Imaging biomarkers can predict therapeutic efficacy and reveal mechanisms of drug resistance.
- Multimodal imaging combined with molecular biology enhances understanding of tumor heterogeneity and immune microenvironment.

## Abstract

Functional and metabolic imaging (e.g., PET, CEST-MRI) is pivotal for early tumor response assessment and deciphering drug resistance, outperforming traditional anatomical imaging. This review synthesizes key technologies (e.g., 18F-FDG, hyperpolarized 13C-MRI) and their roles in predicting therapeutic efficacy and characterizing tumor heterogeneity. It critically evaluates limitations, clinical validation, and variability of imaging biomarkers, distinguishing between actionable clinical tools and investigational candidates. Addressing real-world barriers (cost, standardization), it outlines future directions to advance imaging-guided precision oncology.

Early assessment of tumor treatment response and elucidation of resistance mechanisms are critical for optimizing therapeutic strategies and improving patient outcomes. Functional and metabolic imaging technologies, particularly positron emission tomography (PET) combined with specific tracers, enable dynamic monitoring of tumor cell metabolism and microenvironmental changes during the initial phases of therapy. This capability facilitates early prediction of treatment efficacy and investigation into mechanisms underlying drug resistance. This review synthesizes recent advances in the application of functional and metabolic imaging for early tumor treatment response evaluation and resistance assessment. Emphasis is placed on integrating multimodal imaging techniques with molecular biology approaches to comprehensively analyze the relationships among imaging biomarkers, tumor heterogeneity, immune microenvironment, and molecular pathways. The article further explores the clinical translational potential of these imaging modalities while addressing current challenges and limitations. By providing an updated overview of this rapidly evolving field, this review aims to guide future research and clinical application toward more precise and personalized oncology care.