Model-aided quantification of patient-specific benefit in mitigating radiation induced lymphopenia by particle therapy of cancer

TL;DR

This paper introduces a biokinetic model that predicts patient-specific lymphopenia severity during radiotherapy, demonstrating particle therapy's immune-sparing advantage and enabling personalized treatment planning.

Contribution

The study develops and validates a mechanistic model linking radiation dose, immune response, and clinical outcomes, a novel approach in predicting lymphopenia in cancer therapy.

Findings

Model accurately predicts lymphocyte counts across diverse datasets.

Particle therapy reduces lymphocyte depletion by approximately 30%.

The framework links physics, biology, and clinical data for personalized treatment.

Abstract

Treatment-related lymphopenia is a frequent and clinically significant consequence of cancer therapy that can compromise immune-mediated tumor control and worsen patient outcomes. Despite its importance, no mechanistic framework exists to accurately predict the severity of lymphopenia from patient-specific data. Here, we present a biokinetic model that quantitatively describes lymphocyte depletion and recovery during and after radiotherapy, integrating radiation dose-volume distributions, blood circulation dynamics, and distinct kinetics of fast- and slow-recovering lymphocyte populations. The model was calibrated and validated using 56 independent clinical datasets encompassing various tumor sites and treatment modalities. It reproduces observed lymphocyte counts and enables prediction of individual severity of lymphopenia from baseline or early-treatment counts. Applying this framework, we demonstrate that particle therapy reduces lymphocyte depletion by ~30% compared with photon therapy, providing a quantitative explanation for its observed immune-sparing benefit. By linking radiation physics, immune kinetics, and clinical outcomes, our model establishes a mechanistically grounded predictive approach for anticipating systemic immune toxicity. Beyond radiotherapy, this framework offers a generalizable strategy for integrating early biological markers into treatment optimization, advancing personalized and immune-preserving cancer therapy.