Medical imaging in personalised medicine: a white paper of the research committee of the European Society of Radiology (ESR)

Abstract

The future of medicine lies in early diagnosis and individually tailored treatments, a concept that has been designated 'personalised medicine' (PM), i.e. delivering the right treatment to the right patient at the right time. However, the value of medical imaging in PM is frequently underestimated, as many policy makers forget the all-important right location in the PM paradigm. Medical imaging has always been personalised as it provides individual assessment of the location and extent of an abnormality, and in the future it will prove fundamental to almost all aspects of PM. Stratification based on imaging biomarkers can help identify individuals suited for preventive intervention and can improve disease staging. In vivo visualisation of locoregional physiological, biochemical and biological processes using molecular imaging can detect diseases in pre-symptomatic phases or facilitate individualised drug delivery. Furthermore, imaging is essential to patient-tailored therapy planning, therapy monitoring and follow-up of disease progression, as well as targeting non-invasive or minimally invasive treatments, especially with the rise of theranostics. For PM to reach its full potential, medical imaging must be an integral part. Radiologists need to be prepared for this new paradigm as it will mean changes in training, in research and in clinical practice.

Fig. 1

Imaging to identify beneficiaries of preventive medicine. Elevated calcium score with associated chronic total occlusion of the left anterior descending coronary artery (LAD) in a 79-year-old male. a Axial unenhanced image shows calcifications in the LAD, in the circumflex (CX) coronary artery and in the right coronary artery (RCA). b The calcifications in the three coronary arteries are colour coded by the automated calcium detection algorithm. The total Agatston calcium score in this patient was 637, suggesting increased risk for a coronary event. c CT coronary angiography demonstrates an obstructive coronary stenosis due a mixed plaque in the proximal LAD (C1) and a chronic total occlusion in the mid LAD (C2)

Fig. 2a, b

Novel imaging techniques contribute to personalised diagnosis. Delayed gadolinium-enhanced magnetic resonance imaging of cartilage (dGEMRIC) in a patient with complaints of early knee osteoarthritis (a) and a patient without knee complaints (b). With dGEMRIC it is possible to quantitatively assess cartilage quality before the onset of morphological changes, by measuring its glycosaminoglycan content. In patient a, decreased dGEMRIC index is shown particularly in the weight-bearing cartilage of the femoral condyle and tibial plateau compared to patient b. This indicates reduced glycosaminoglycan content, and hence reduced cartilage quality, in the early osteoarthritic knee. Novel quantitative radiological techniques such as dGEMRIC may aid in personalised therapeutic decision-making in early stage osteoarthritis because patients who are likely to benefit from therapeutic interventions can be identified more accurately

Fig. 3

¹⁸FDG imaging to monitor cancer treatment. Computed tomography (CT, left), ¹⁸FDG positron emission tomography (PET, right) and PET/CT fusion (middle) images in a patient with Hodgkin’s lymphoma, evaluated after eight courses of chemotherapy. Intense hypermetabolism on FDG-PET corresponds with localisation on CT in a small right supraclavicular lymph node, clearly indicating recurrent lymphoma. (Figure courtesy of Dr. Roelf Valkema, Department of Nuclear Medicine, Erasmus MC)