Can MR textural analysis improve the prediction of extracapsular nodal spread in patients with oral cavity cancer?

OBJECTIVE: To explore the utility of MR texture analysis (MRTA) for detection of nodal extracapsular spread (ECS) in oral cavity squamous cell carcinoma (SCC). METHODS: 115 patients with oral cavity SCC treated with surgery and adjuvant (chemo)radiotherapy were identified retrospectively. First-order texture parameters (entropy, skewness and kurtosis) were extracted from tumour and nodal regions of interest (ROIs) using proprietary software (TexRAD). Nodal MR features associated with ECS (flare sign, irregular capsular contour; local infiltration; nodal necrosis) were reviewed and agreed in consensus by two experienced radiologists. Diagnostic performance characteristics of MR features of ECS were compared with primary tumour and nodal MRTA prediction using histology as the gold standard. Receiver operating characteristic (ROC) and regression analyses were also performed. RESULTS: Nodal entropy derived from contrast-enhanced T1-weighted images was significant in predicting ECS (p = 0.018). MR features had varying accuracy: flare sign (70%); irregular contour (71%); local infiltration (66%); and nodal necrosis (64%). Nodal entropy combined with irregular contour was the best predictor of ECS (p = 0.004, accuracy 79%). CONCLUSION: First-order nodal MRTA combined with imaging features may improve ECS prediction in oral cavity SCC. KEY POINTS: • Nodal MR textural analysis can aid in predicting extracapsular spread (ECS). • Medium filter contrast-enhanced T1 nodal entropy was strongly significant in predicting ECS. • Combining nodal entropy with irregular nodal contour improves predictive accuracy.

Evaluation of current algorithms for segmentation of scar tissue from late gadolinium enhancement cardiovascular magnetic resonance of the left atrium: an open-access grand challenge.

BACKGROUND: Late Gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR) imaging can be used to visualise regions of fibrosis and scarring in the left atrium (LA) myocardium. This can be important for treatment stratification of patients with atrial fibrillation (AF) and for assessment of treatment after radio frequency catheter ablation (RFCA). In this paper we present a standardised evaluation benchmarking framework for algorithms segmenting fibrosis and scar from LGE CMR images. The algorithms reported are the response to an open challenge that was put to the medical imaging community through an ISBI (IEEE International Symposium on Biomedical Imaging) workshop. METHODS: The image database consisted of 60 multicenter, multivendor LGE CMR image datasets from patients with AF, with 30 images taken before and 30 after RFCA for the treatment of AF. A reference standard for scar and fibrosis was established by merging manual segmentations from three observers. Furthermore, scar was also quantified using 2, 3 and 4 standard deviations (SD) and full-width-at-half-maximum (FWHM) methods. Seven institutions responded to the challenge: Imperial College (IC), Mevis Fraunhofer (MV), Sunnybrook Health Sciences (SY), Harvard/Boston University (HB), Yale School of Medicine (YL), King's College London (KCL) and Utah CARMA (UTA, UTB). There were 8 different algorithms evaluated in this study. RESULTS: Some algorithms were able to perform significantly better than SD and FWHM methods in both pre- and post-ablation imaging. Segmentation in pre-ablation images was challenging and good correlation with the reference standard was found in post-ablation images. Overlap scores (out of 100) with the reference standard were as follows: Pre: IC = 37, MV = 22, SY = 17, YL = 48, KCL = 30, UTA = 42, UTB = 45; Post: IC = 76, MV = 85, SY = 73, HB = 76, YL = 84, KCL = 78, UTA = 78, UTB = 72. CONCLUSIONS: The study concludes that currently no algorithm is deemed clearly better than others. There is scope for further algorithmic developments in LA fibrosis and scar quantification from LGE CMR images. Benchmarking of future scar segmentation algorithms is thus important. The proposed benchmarking framework is made available as open-source and new participants can evaluate their algorithms via a web-based interface.

Feasibility Study on Using Dynamic Contrast Enhanced MRI to Assess the Effect of Tyrosine Kinase Inhibitor Therapy within the STAR Trial of Metastatic Renal Cell Cancer.

Objective: To identify dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) parameters predictive of early disease progression in patients with metastatic renal cell cancer (mRCC) treated with anti-angiogenic tyrosine kinase inhibitors (TKI). Methods: The study was linked to a phase II/III randomised control trial. Patients underwent DCE-MRI before, at 4- and 10-weeks after initiation of TKI. DCE-MRI parameters at each time-point were derived from a single-compartment tracer kinetic model, following semi-automated tumour segmentation by two independent readers. Primary endpoint was correlation of DCE-MRI parameters with disease progression at 6-months. Receiver operating characteristic (ROC) curve analysis and area under the curve (AUC) values were calculated for parameters associated with disease progression at 6 months. Inter-observer agreement was assessed using the intraclass correlation coefficient (ICC). Results: 23 tumours in 14 patients were measurable. Three patients had disease progression at 6 months. The percentage (%) change in perfused tumour volume between baseline and 4-week DCE-MRI (p = 0.016), mean transfer constant Ktrans change (p = 0.038), and % change in extracellular volume (p = 0.009) between 4- and 10-week MRI, correlated with early disease progression (AUC 0.879 for each parameter). Inter-observer agreement was excellent for perfused tumour volume, Ktrans and extracellular volume (ICC: 0.928, 0.949, 0.910 respectively). Conclusions: Early measurement of DCE-MRI biomarkers of tumour perfusion at 4- and 10-weeks predicts disease progression at 6-months following TKI therapy in mRCC.

The Impact of COVID-19 on Interventional Radiology Services in the UK.

INTRODUCTION: The coronavirus disease 2019 (COVID-19) has created unprecedented challenges on the healthcare system. The aim of this multi-centre study was to measure the impact of COVID-19 on IR services in the UK. MATERIAL AND METHODS: Retrospective cross-sectional study of IR practice in six UK centres during the COVID-19 pandemic was carried out. All therapeutic IR procedures were identified using the respective hospital radiology information systems and COVID-19 status found on the hospital patient record systems. The total number of therapeutic IR procedures was recorded over two time periods, 25/03/2019-21/04/2019 (control group) and 30/03/2020-26/04/2020 (COVID-19 group). The data points collected were: procedure type, aerosol-generating nature, acute or elective case, modality used, in- or out-of-hours case and whether the procedure was done at the bedside (portable). RESULTS: A 31% decrease in overall number of IR procedures was observed during COVID-19 compared to the control group (1363 cases vs 942 cases); however, the acute work decreased by only 0.5%. An increase in out-of-hours work by 10% was observed. COVID-19 was suspected or laboratory proved in 9.9% of cases (n = 93), and 15% of total cases (n = 141) were classed as aerosol-generating procedures. A 66% rise in cholecystostomy was noted during COVID-19. Image-guided ablation, IVC filters, aortic stent grafting and visceral vascular stenting had the greatest % decreases in practice during COVID-19, with 91.7%, 83.3%, 80.8% and 80.2% decreases, respectively. CONCLUSION: During the global pandemic, IR has continued to provide emergency and elective treatment highlighting the adaptability of IR in supporting other specialties.

Correction to: Long-Term Outcomes in Percutaneous Radiofrequency Ablation for Histologically Proven Colorectal Lung Metastasis.

In the introduction section on line 7, the following sentence "A large epidemiological study of colorectal cancer patients with lung metastases found 3 and 5-year survival rates of 1.3% and 6.9%" should actually be "A large epidemiological study of colorectal cancer patients with lung metastases found 3 and 5-year survival rates of 11.3% and 6.9%".

Long-Term Outcomes in Percutaneous Radiofrequency Ablation for Histologically Proven Colorectal Lung Metastasis.

INTRODUCTION: To evaluate the long-term outcome of image-guided radiofrequency ablation (RFA) when treating histologically confirmed colorectal lung metastasis in terms of overall survival (OS), progression-free survival (PFS) and local tumour control (LTC). MATERIALS AND METHODS: Retrospective single-centre study. Consecutive RFA treatments of histologically proven lung colorectal metastases between 01/01/2008 and 31/12/14. The primary outcome was patient survival (OS and PFS). Secondary outcomes were local tumour progression (LTP) and complications. Prognostic factors associated with OS/ PFS were determined by univariate and multivariate analyses. RESULTS: Sixty patients (39 males: 21 females; median age 69 years) and 125 colorectal lung metastases were treated. Eighty percent (n = 48) also underwent lung surgery for lung metastases. Mean metastasis size (cm) was 1.4 ± 0.6 (range 0.3-4.0). Median number of RFA sessions was 1 (1-4). During follow-up (median 45.5 months), 45 patients died (75%). The estimated OS and PFS survival rates at 1, 3, 5, 7, 9 years were 96.7%, 74.7%, 44.1%, 27.5%, 16.3% (median OS, 52 months) and 66.7%, 31.2%, 25.9%, 21.2% and 5.9% (median PFS, 19 months). The LTC rate was 90% with 6 patients developing LTP with 1-, 2-, 3- and 4-year LTP rates of 3.3%, 8.3%, 10.0% and 10.0%. Progression-free interval < 1 year (P = 0.002, HR = 0.375) and total number of pulmonary metastases (≥ 3) treated (P = 0.037, HR = 0.480) were independent negative prognostic factors. Thirty-day mortality rate was 0% with no intra-procedural deaths. CONCLUSION: The long-term OS and PFS following RFA for the treatment of histologically confirmed colorectal lung metastases demonstrate comparable oncological durability to surgery.

Relationship between primary colorectal tumour and location of colorectal liver metastases.

BACKGROUND: There is conflicting evidence regarding whether streamlining of blood flow within the portal vein influences the anatomical distribution of colorectal liver metastases (CRLM). This study assesses the relationship between primary tumour location and metastases location. METHODS: Patients were identified using a prospectively maintained database, and those with known site of primary colorectal tumour and hemiliver involvement were included. Site of metastases and segments affected were confirmed via review of the radiology reports. The location of primary colonic tumour was confirmed via review of clinical correspondence letters. RESULTS: A total of 2364 metastases were identified in 891 patients. Of these, 379 metastases were in the right lobe and 156 in the left lobe, with 356 having bilobar disease. There was no significant relationship between the distribution of CRLM and the site of primary disease (left colon versus right colon) (P = 0.819). However, when the segmental location of the metastases was considered, there is a statistically significant difference between the number of right-sided CRLM compared with left-sided CRLM (P < 0.001). CONCLUSIONS: Right-sided CRLM is more likely regardless of the primary location. Portal streaming may have an effect, although the natural anatomical 'angulation', particularly of the left portal vein branch is more likely to play a role.

Complete Absence of Iliac Arteries in the Left Hemipelvis in a Case of Deceased Donor Renal Transplantation.

Renal transplantation is an established method of treating end-stage renal failure. Whilst the majority of procedures follow a standard technique, vascular anomalies may pose intraoperative challenges and, therefore, careful preoperative assessment is warranted. We present a unique, complex case compounded by complete absence of iliac arteries in the left hemipelvis in association with double inferior vena cava in a young recipient.