Understanding the PULSAR Effect in Combined Radiotherapy and Immunotherapy through Attention Mechanisms with a Transformer Model

Hao Peng; Casey Moore; Debabrata Saha; Steve Jiang; Robert Timmerman

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arXiv · 2403.04175

Understanding the PULSAR Effect in Combined Radiotherapy and Immunotherapy through Attention Mechanisms with a Transformer Model

Hao Peng·Casey Moore·Debabrata Saha·Steve Jiang·Robert Timmerman

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Abstract

PULSAR (personalized, ultra-fractionated stereotactic adaptive radiotherapy) is the adaptation of stereotactic ablative radiotherapy towards personalized cancer management. For the first time, we applied a transformer-based attention mechanism to investigate the underlying interactions between combined PULSAR and PD-L1 blockade immunotherapy based on a murine cancer model (Lewis Lung Carcinoma, LLC). The proposed approach is able to predict the trend of tumor volume change semi-quantitatively, and excels in identifying the potential causal relationships through both self-attention and cross-attention scores.

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Hao Peng, Casey Moore, Debabrata Saha, Steve Jiang, Robert Timmerman. 2024-03-07. Understanding the PULSAR Effect in Combined Radiotherapy and Immunotherapy through Attention Mechanisms with a Transformer Model. https://arxiv.org/abs/2403.04175

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