State-of-the-Art Imaging in Human Chordoma of the Skull Base

Abstract

Purpose of ReviewChordoma are rare tumours of the axial skeleton which occur most often at the base of the skull and in the sacrum. Although chordoma are generally slow-growing lesions, the recurrence rate is high and the location makes it often difficult to treat. Both computed tomography (CT) and magnetic resonance imaging (MRI) are crucial in the initial diagnosis, treatment planning and post-treatment follow-up.Recent FindingsBasic MRI and CT characteristics of chordoma were described in the late 1980s and early 1990s. Since then, imaging techniques have evolved with increased resolution and new molecular imaging tools are rapidly evolving. New imaging tools have been developed not only to study anatomy, but also physiologic changes and characterization of tissue and assessment of tumour biology. Recent studies show the uptake of multiple PET tracers in chordoma, which may become an important aspect in the diagnosis, follow-up and personalized therapy.SummaryThis review gives an overview of skull base chordoma histopathology, classic imaging characteristics, radiomics and state-of-the-art imaging techniques that are now emerging in diagnosis, treatment planning and disease monitoring of skull base chordoma.

Radiomics and Dosiomics for Predicting Local Control after Carbon-Ion Radiotherapy in Skull-Base Chordoma

“…Due to the limited data available, it was not possible to separately investigate the potential confounding factors (contouring, intrinsic features reproducibility, variations in acquisition parameters) which are known to affect the computation of radiomic features [ 33 ]. Nonetheless, given the radiological relevance of chordoma appearance on MRI [ 11 ], from which haemorrhage, calcifications and other heterogeneous structures can be identified, quantitative (e.g., diffusion-weighted MRI) and standardized anatomical MR sequences (e.g., fat-saturated or contrast-enhanced) should be explored as promising sources of prognostic features [ 27 , 34 , 35 ]. Indeed, textural wavelet features from anatomical T1w- and T2w-MRI showed to be promising for SBC treated with surgery [ 28 ].…”

“…Although CT offers a lower soft tissue contrast than MRI, the selected CT features ( supplementary materials, Figure S3 ) showed comparable or higher validation C-indices with respect to MRI. This could be due to the tendency of chordomas to segregate, infiltrate and destroy bone structures [ 11 ], which are well identifiable on CT imaging. This observation seems to be supported by the choice of features pertaining low (10th percentile) or high (GLRLM HGLRE) or differences between low and high (rMAD) HU values, in the best performing cases.…”

“…In this context, the growing availability of imaging data can be favourably exploited as a source of prognostic factors [ 8 , 9 ], with studies in the literature supporting the predictive power of the appearance of chordomas on diagnostic imaging, such as CT and MRI [ 10 ]. More recently, qualitative imaging factors are being complemented by quantitative ones, such as radiomic features [ 11 ].…”

Clival chordoma in a young male patient: a case report

“…However, MRI does not describe well cortical bone involvement and/or destruction. Yet, it remains the best imaging technique in evaluating tumor size and extension after radiation therapy [ 3 ]. Pathologic examination of biopsies specimens or exised tumor masses is curcial to identify the tumor nature and judge the completeness of surgical excision.…”

Long and Very-Long-Chain Ceramides Correlate with A More Aggressive Behavior in Skull Base Chordoma Patients

“…The radiological appearance of SBC is very heterogeneous and has been scarcely described and correlated with prognosis in the literature [59,60]. The degree of contrast enhancement in chordoma is not systematically described and is not considered in the modern clinical and radiological patient management as a prognostic factor in SBC [60,61]. On the ground of previous confirmatory quantitative radiomics results, we adopted the following classification of MR enhancement pattern: intense enhancement, mild enhancement and no enhancement that revealed to be very simple to use, fast-forward, and reliable [60].…”