Imaging-based representation and stratification of intra-tumor Heterogeneity via tree-edit distance

TL;DR

This paper introduces a novel tree-based radiomics approach to non-invasively characterize intra-tumor heterogeneity from PET/CT images, aiding in cancer subtyping and treatment planning.

Contribution

It presents a new hierarchical tree representation and a heterogeneity-based distance metric for tumor analysis, outperforming existing methods.

Findings

Tree-based heterogeneity representation effectively clusters prostate cancer patients.

The method correlates well with tumor severity and biological features.

Outperforms current literature approaches in tumor subtyping.

Abstract

Personalized medicine is the future of medical practice. In oncology, tumor heterogeneity assessment represents a pivotal step for effective treatment planning and prognosis prediction. Despite new procedures for DNA sequencing and analysis, non-invasive methods for tumor characterization are needed to impact on daily routine. On purpose, imaging texture analysis is rapidly scaling, holding the promise to surrogate histopathological assessment of tumor lesions. In this work, we propose a tree-based representation strategy for describing intra-tumor heterogeneity of patients affected by metastatic cancer. We leverage radiomics information extracted from PET/CT imaging and we provide an exhaustive and easily readable summary of the disease spreading. We exploit this novel patient representation to perform cancer subtyping according to hierarchical clustering technique. To this purpose, a new heterogeneity-based distance between trees is defined and applied to a case study of prostate cancer. Clusters interpretation is explored in terms of concordance with severity status, tumor burden and biological characteristics. Results are promising, as the proposed method outperforms current literature approaches. Ultimately, the proposed method draws a general analysis framework that would allow to extract knowledge from daily acquired imaging data of patients and provide insights for effective treatment planning.