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Radiomics describes the extraction of multiple features from medical images, including molecular imaging modalities, that with bioinformatic approaches, provide additional clinically relevant information that may be invisible to the human eye. This information may complement standard radiological interpretation with data that may better characterize a disease or that may provide predictive or prognostic information. Progressing from predefined image features, often describing heterogeneity of voxel intensities within a volume of interest, there is increasing use of machine learning to classify disease characteristics and deep learning methods based on artificial neural networks that can learn features without a priori definition and without the need for preprocessing of images. There have been advances in standardization and harmonization of methods to a level that should support multicenter studies. However, in this relatively early phase of research in the field, there are limited aspects that have been adopted into routine practice. Most of the reports in the molecular imaging field describe radiomic approaches in cancer using 18F-fluorodeoxyglucose positron emission tomography (18F-FDG-PET). In this review, we will describe radiomics in molecular imaging and summarize the pertinent literature in lung cancer where reports are most prevalent and mature. [ABSTRACT FROM AUTHOR]

Better predictive markers are needed to deliver individualized care for patients with primary esophagogastric cancer. This exploratory study aimed to assess whether pre-treatment imaging parameters from dynamic contrast-enhanced MRI and 18F-fluorodeoxyglucose (18F-FDG) PET/CT are associated with response to neoadjuvant therapy or outcome. Following ethical approval and informed consent, prospective participants underwent dynamic contrast-enhanced MRI and 18F-FDG PET/CT prior to neoadjuvant chemotherapy/chemoradiotherapy ± surgery. Vascular dynamic contrast-enhanced MRI and metabolic 18F-FDG PET parameters were compared by tumor characteristics using Mann Whitney U test and with pathological response (Mandard tumor regression grade), recurrence-free and overall survival using logistic regression modelling, adjusting for predefined clinical variables. 39 of 47 recruited participants (30 males; median age 65 years, IQR: 54, 72 years) were included in the final analysis. The tumor vascular-metabolic ratio was higher in patients remaining node positive following neoadjuvant therapy (median tumor peak enhancement/SUV max ratio: 0.052 vs. 0.023, p = 0.02). In multivariable analysis adjusted for age, gender, pre-treatment tumor and nodal stage, peak enhancement (highest gadolinium concentration value prior to contrast washout) was associated with pathological tumor regression grade. The odds of response decreased by 5% for each 0.01 unit increase (OR 0.95; 95% CI: 0.90, 1.00, p = 0.04). No 18F-FDG PET/CT parameters were predictive of pathological tumor response. No relationships between pre-treatment imaging and survival were identified. Pre-treatment esophagogastric tumor vascular and metabolic parameters may provide additional information in assessing response to neoadjuvant therapy. [ABSTRACT FROM AUTHOR]

As an integrated system, hybrid positron emission tomography/magnetic resonance imaging (PET/MRI) is able to provide simultaneously complementary high-resolution anatomic, molecular, and functional information, allowing comprehensive cancer phenotyping in a single imaging examination. In addition to an improved patient experience by combining 2 separate imaging examinations and streamlining the patient pathway, the superior soft tissue contrast resolution of MRI and the ability to acquire multiparametric MRI data is advantageous over computed tomography. For gastrointestinal cancers, this would improve tumor staging, assessment of neoadjuvant response, and of the likelihood of a complete (R0) resection in comparison with positron emission tomography or computed tomography. [ABSTRACT FROM AUTHOR]

Hepatocyte-specific contrast agents have been made available in the last 15 years for magnetic resonance imaging of the liver. These agents are differentially taken up by functioning hepatocytes and excreted in the biliary system. They can help distinguish focal liver lesions of hepatocellular origin from lesions of nonhepatocellular origin, and can also be used in the evaluation of the biliary tree. The purpose of this review is to summarize the different types of hepatocyte-specific contrast agents presently available, their use in the characterization of focal liver lesions, their role in the evaluation of biliary pathology, and their potential future applications. [Copyright &y& Elsevier]

Anatomical-based imaging is used widely for the evaluation of diffuse and focal liver, including detection, characterization, and therapy response assessment. However, a limitation of anatomical-based imaging is that structural changes may occur relatively late in a disease process. By applying conventional anatomical-imaging methods in a more functional manner, specific pathophysiologic alterations of the liver may be assessed and quantified. There has been an increasing interest in both the clinical and research settings, with the expectation that functional-imaging techniques may help solve common diagnostic dilemmas that conventional imaging alone cannot. This review considers the most common functional magnetic resonance imaging, computed tomography, and ultrasound imaging techniques that may be applied to the liver. [Copyright &y& Elsevier]

Abstract: The aim was to determine the feasibility of vascular quantification of the bowel wall for different anatomical segments of the colorectum. Following institutional ethical approval and informed consent, 39 patients with colorectal cancer underwent perfusion CT. Blood flow (BF), blood volume (BV), mean transit time (MTT), and permeability surface area product (PS) were assessed for different segments of the colorectum: ascending, transverse, descending colon, sigmoid, or rectum, that were distant from the tumor, and which were proven normal on contemporary colonoscopy, and subsequent imaging and clinical follow up. Mean (SD) for BF, BV, MTT and PS for the different anatomical colorectal segments were obtained and compared using a pooled t-test. Significance was at 5%. Assessment was not possible in 9 of 39 (23%) patients as the bowel wall was ≤5mm precluding quantitative analysis. Forty-four segments were evaluated in the remaining 30 patients. Mean BF was higher in the proximal than distal colon: 24.0 versus 17.8mL/min/100g tissue; p =0.009; BV, MTT and PS were not significantly different; BV: 3.46 versus 3.15mL/100g tissue, p =0.45; MTT: 15.1 versus 18.3s; p =0.10; PS: 6.84 versus 8.97mL/min/100 tissue, p =0.13, respectively. In conclusion, assessment of bowel wall perfusion may fail in 23% of patients. The colorectum demonstrates segmental differences in perfusion. [Copyright &y& Elsevier]

Purpose: To describe the MRI appearances of squamous cell carcinoma of the anal canal before and after chemoradiation and to assess whether MRI features predict for clinical outcome. Methods and Materials: Thirty-five patients (15 male, 20 female; mean age 60.8 years) with histologically proven squamous cell cancer of the anal canal underwent MRI before and 6–8 weeks after definitive chemoradiation. Images were reviewed retrospectively by two radiologists in consensus blinded to clinical outcome: tumor size, signal intensity, extent, and TNM stage were recorded. Following treatment, patients were defined as responders by T and N downstaging and Response Evaluation Criteria in Solid Tumors (RECIST). Final clinical outcome was determined by imaging and case note review: patients were divided into (1) disease-free and (2) with relapse and compared using appropriate univariate methods to identify imaging predictors; statistical significance was at 5%. Results: The majority of tumors were ≤T2 (23/35; 65.7%) and N0 (21/35; 60%), mean size 3.75cm, and hyperintense (++ to +++, 24/35 patients; 68%). Following chemoradiation, there was a size reduction in all cases (mean 73.3%) and a reduction in signal intensity in 26/35 patients (74.2%). The majority of patients were classified as responders (26/35 (74.2%) patients by T and N downstaging; and 30/35 (85.7%) patients by RECIST). At a median follow-up of 33.5 months, 25 patients (71.4%) remained disease-free; 10 patients (28.6%) had locoregional or metastatic disease. Univariate analysis showed that no individual MRI features were predictive of eventual outcome. Conclusion: Early assessment of response by MRI at 6–8 weeks is unhelpful in predicting future clinical outcome. [ABSTRACT FROM AUTHOR]

Abstract: We aim to assess the spatial distribution of blood volume (BV) in whole lung tumours in patients undergoing radiotherapy using helical dynamic contrast enhanced computed tomography (DCE-CT), and to determine whether conventional single level, or whole tumour measurements is more representative of the vascular effects of radiotherapy. Following ethical approval and informed consent, 15 patients with histologically proven non-small cell lung cancer underwent paired helical DCE-CT studies at baseline to assess repeatability, and after two fractions of radiotherapy (9Gy total dose). Tumour BV was calculated for individual contiguous 10mm axial slices, and for the entire tumour volume on a pixel-per-pixel basis. Baseline tumour BV was heterogeneous varying by 15.33%±17.11 between adjacent 10mm axial slices. Within subject coefficient of variation was 36.72% with conventional single tumour level evaluation, and 13.62% with whole tumour measurements. Following radiotherapy, one patient had an increase in BV greater than baseline variation (derived from the 95% limits of change) using single level evaluation; in contrast, seven patients had an increase in BV when the whole tumour was assessed. As a group, following radiotherapy, mean BV increased by 17.27% (paired t-test, p =0.20) with single level evaluation and 19.26% (p =0.049) with whole tumour assessment. Tumour BV measured using DCE-CT is spatially heterogeneous. Given the slice-by-slice variation in blood volume, our results demonstrate that whole tumour DCE-CT measurements are more repeatable, and may be a better predictor of vascular changes following therapy, compared to conventional single tumour level evaluations. [Copyright &y& Elsevier]

Purpose: The tumor vascular effects of radiotherapy and subsequent administration of the vascular disrupting agent combretastatin A4 phosphate (CA4P) were studied in patients with advanced non–small-cell lung cancer using volumetric dynamic contrast–enhanced computed tomography (CT). Patients and Methods: Following ethical committee approval and informed consent, 8 patients receiving palliative radiotherapy (27 Gy in six fractions, twice weekly) also received CA4P (50 mg/m2) after the second fraction of radiotherapy. Changes in dynamic CT parameters of tumor blood volume (BV) and permeability surface area product (PS) were measured for the whole tumor volume, tumor rim, and center after radiotherapy alone and after radiotherapy in combination with CA4P. Results: After the second fraction of radiotherapy, 6 of the 8 patients showed increases in tumor PS (23.6%, p = 0.011). Four hours after CA4P, a reduction in tumor BV (22.9%, p < 0.001) was demonstrated in the same 6 patients. Increase in PS after radiotherapy correlated with reduction in BV after CA4P (r = 0.77, p = 0.026). At 72 h after CA4P, there was a sustained reduction in tumor BV of 29.4% (p < 0.001). Both increase in PS after radiotherapy and reduction in BV after CA4P were greater at the rim of the tumor. The BV reduction at the rim was sustained to 72 h (51.4%, p = 0.014). Conclusion: Radiotherapy enhances the tumor antivascular activity of CA4P in human non–small-cell lung cancer, resulting in sustained tumor vascular shutdown. [Copyright &y& Elsevier]

Summary: Angiogenesis is a key factor in the growth and dissemination of colorectal cancer, with significant implications for its clinical management. Previous trials have provided proof-of-principle that inhibition of angiogenesis has the potential to enhance the effectiveness of treatment for this disease. Characterisation of the angiogenic status of the tumour on an individual patient basis could allow for a more targeted approach to treatment. In vivo imaging techniques that assess tumour microvessel function have the potential to improve the management of treatment for patients with colorectal cancer. This review focuses on MRI and CT assessment of colorectal cancer angiogenesis. We discuss the effects that these two techniques have had in the assessment of this disease, including tumour staging and therapeutic assessment. Their comparability with other imaging techniques, in particular ultrasound, and their limitations are also addressed. [Copyright &y& Elsevier]

Purpose: To quantitatively assess the in vivo acute vascular effects of fractionated radiotherapy for human non-small-cell lung cancer using volumetric perfusion computed tomography (CT). Methods and Materials: Sixteen patients with advanced non-small-cell lung cancer, undergoing palliative radiotherapy delivering 27 Gy in 6 fractions over 3 weeks, were scanned before treatment, and after the second (9 Gy), fourth (18 Gy), and sixth (27 Gy) radiation fraction. Using 16-detector CT, multiple sequential volumetric acquisitions were acquired after intravenous contrast agent injection. Measurements of vascular blood volume and permeability for the whole tumor volume were obtained. Vascular changes at the tumor periphery and center were also measured. Results: At baseline, lung tumor vascularity was spatially heterogeneous with the tumor rim showing a higher vascular blood volume and permeability than the center. After the second, fourth, and sixth fractions of radiotherapy, vascular blood volume increased by 31.6% (paired t test, p = 0.10), 49.3% (p = 0.034), and 44.6% (p = 0.0012) respectively at the tumor rim, and 16.4% (p = 0.29), 19.9% (p = 0.029), and 4.0% (p = 0.0050) respectively at the center of the tumor. After the second, fourth, and sixth fractions of radiotherapy, vessel permeability increased by 18.4% (p = 0.022), 44.8% (p = 0.0048), and 20.5% (p = 0.25) at the tumor rim. The increase in permeability at the tumor center was not significant after radiotherapy. Conclusion: Fractionated radiotherapy increases tumor vascular blood volume and permeability in human non-small-cell lung cancer. We have established the spatial distribution of vascular changes after radiotherapy; greater vascular changes were demonstrated at the tumor rim compared with the center. [ABSTRACT FROM AUTHOR]

Summary: Background: Nitric oxide has been implicated in tumour angiogenesis and in the maintaining of vasodilator tone of tumour blood vessels. The tumour vascular effects of inhibition of nitric-oxide synthesis have not been investigated in patients with cancer. Methods: Seven women and 11 men (12 with non-small-cell lung cancer, five prostate cancer, and one cervical cancer) were recruited onto a phase I dose-escalation study and received a single dose of the nitric oxide synthase inhibitor, N-nitro-L-arginine (L-NNA). Dose escalation was done by a modified Fibonacci scale with three patients at each dose level, starting with 0·1 mg/kg. Changes in dynamic contrast-enhanced CT measures of tumour relative blood volume and transfer constant (K) were measured at 1 h and 24 h after L-NNA administration. Findings: In the 18 patients, toxic effects were self-limiting cardiovascular changes: three patients had Common Toxicity Criteria version 2.0 grade 1 hypertension; two had grade 1 sinus bradycardia; and one had grade 1 palpitation. L-NNA area under the curve (AUC) increased linearly with dose from 163 μmol min−1 L−1 at 0·1 mg/kg L-NNA to 2150 μmol min−1 L−1 at 0·9 mg/kg L-NNA. In eight patients that underwent dynamic CT scanning, tumour blood volume decreased 1 h after L-NNA treatment (mean 42·9% [range 12·0–62·1]; paired t test p=0·0070), which was sustained for up to 24 h (mean 33·9% [range 6·5–64·9]; p=0·035). This decrease in blood volume was associated with an increase in the number of non-perfused pixels from 7·3% (SD 5·5) at baseline to 25·1% (15·3; p=0·0089) at 1 h, and 18·2% (12·9; p=0·050) at 24 h. There was a significant correlation between L-NNA plasma AUC and the reduction in tumour blood volume at 24 h after L-NNA (r=0·83; p=0·010). Interpretation: We have shown in vivo in patients with cancer that nitric oxide has a role in maintaining tumour blood supply, and we provide early clinical evidence that inhibition of nitric-oxide synthesis has tumour antivascular activity. [Copyright &y& Elsevier]

Perfusion CT was first described in the 1970s but has become accepted as a clinical technique in recent years. In oncological practice Perfusion CT allows the downstream effects of therapies on the tumour vasculature to be monitored. From the dynamic changes in tumour and vascular enhancement following intravenous iodinated contrast agent administration, qualitative and quantitative parameters may be derived that reflect tumour perfusion, blood volume, and microcirculatory changes with treatment. This review outlines the mechanisms of action of available therapies and state-of-the-art imaging practice. [ABSTRACT FROM AUTHOR]

Objectives: Given the limited diagnostic accuracy of radiographs on presentation to the emergency department (ED), the management of suspected scaphoid fractures remains clinically challenging and poses an unknown economic burden to healthcare systems. We aimed to evaluate the cost-effectiveness of immediate magnetic resonance imaging (MRI) in the management of patients presenting with suspected scaphoid fracture to an ED in England.Methods: A pragmatic, randomized, single-center trial compared the use of immediate MRI in the ED against standard care with radiographs only. Participants' use of healthcare services and costs were estimated from primary care and secondary care databases and questionnaires at baseline, 1, 3, and 6 months postrecruitment. Costs were compared using generalized linear models and combined with quality-adjusted life years (QALYs, based on the EQ-5D-5L) to estimate cost-effectiveness at 6 months postrecruitment. Cost-effectiveness acceptability curves and bootstrapping techniques were used to estimate the probability of cost-effectiveness at different willingness-to-pay (WTP) thresholds. Four deterministic sensitivity scenarios were considered around key parameters.Results: The MRI intervention dominated standard care in the base case and all 4 deterministic sensitivity scenarios, costing less and achieving more QALY gains, with a probability of 100% of being cost-effective at 6 months using the conventional United Kingdom WTP thresholds of £20 000 to £30 000 per QALY.Conclusion: The use of immediate MRI is a cost-effective intervention in the management of suspected scaphoid fractures in a Central Hospital in London. Routine clinical practice at our institution has been changed to include the intervention. [ABSTRACT FROM AUTHOR]

• PET-based radiomic features (RFs) may be able to predict survival. • Initial radiomic studies on lung cancer patients show promising results. • Validation of RFs on external patients cohorts is necessary. • GTV and clinical stage predicted progression free survival (PFS). • None of the preselected RFs predicted independently for PFS. The aim was to validate promising radiomic features (RFs)1 on 18F-flourodeoxyglucose positron emission tomography/computed tomography-scans (18F-FDG PET/CT) of non-small cell lung cancer (NSCLC) patients undergoing definitive chemo-radiotherapy. 18F-FDG PET/CT scans performed for radiotherapy (RT) planning were retrieved. Auto-segmentation with visual adaption was used to define the primary tumour on PET images. Six pre-selected prognostic and reproducible PET texture -and shape-features were calculated using texture respectively shape analysis. The correlation between these RFs and metabolic active tumour volume (MTV)3, gross tumour volume (GTV)4 and maximum and mean of standardized uptake value (SUV)5 was tested with a Spearman's Rank test. The prognostic value of RFs was tested in a univariate cox regression analysis and a multivariate cox regression analysis with GTV, clinical stage and histology. P -value ≤ 0.05 were considered significant. Image analysis was performed for 233 patients: 145 males and 88 females, mean age of 65.7 and clinical stage II-IV. Mean GTV was 129.87 cm3 (SD 130.30 cm3). Texture and shape-features correlated more strongly to MTV and GTV compared to SUV-measurements. Four RFs predicted PFS in the univariate analysis. No RFs predicted PFS in the multivariate analysis, whereas GTV and clinical stage predicted PFS (p = 0.001 and p = 0.008 respectively). The pre-selected RFs were insignificant in predicting PFS in combination with GTV, clinical stage and histology. These results might be due to variations in technical parameters. However, it is relevant to question whether RFs are stable enough to provide clinically useful information. [ABSTRACT FROM AUTHOR]

Purpose: Radiomics describes the extraction of multiple, otherwise invisible, features from medical images that, with bioinformatic approaches, can be used to provide additional information that can predict underlying tumor biology and behavior.Methods and Materials: Radiomic signatures can be used alone or with other patient-specific data to improve tumor phenotyping, treatment response prediction, and prognosis, noninvasively. The data describing 18F-fluorodeoxyglucose positron emission tomography radiomics, often using texture or heterogeneity parameters, are increasing rapidly.Results: In relation to radiation therapy practice, early data have reported the use of radiomic approaches to better define tumor volumes and predict radiation toxicity and treatment response.Conclusions: Although at an early stage of development, with many technical challenges remaining and a need for standardization, promise nevertheless exists that PET radiomics will contribute to personalized medicine, especially with the availability of increased computing power and the development of machine-learning approaches for imaging. [ABSTRACT FROM AUTHOR]

18F-fluorodeoxyglucose (18F-FDG) positron emission tomography–computed tomography (PET/CT) is established for characterising indeterminate pulmonary nodules and staging lung cancer where there is curative intent. Whilst a sensitive technique, specificity for characterising lung cancer is limited. There is recognition that evaluation of other aspects of abnormal cancer biology in addition to glucose metabolism may be more helpful in characterising tumours and predicting response to novel targeted cancer therapeutics. Therefore, efforts have been made to develop and evaluate new radiopharmaceuticals in order to improve the sensitivity and specificity of PET imaging in lung cancer with regards to characterisation, treatment stratification and therapeutic monitoring. 18F-fluorothymidine (18F-FLT) is a marker of cellular proliferation. It shows a lower accumulation in tumours than 18F-FDG as it only accumulates in the cells that are in the S phase of growth and demonstrates a low sensitivity for nodal staging. Its main role is in evaluating treatment response. Methionine is an essential amino acid. 11C-methionine is more specific and sensitive than 18F-FDG in differentiating benign and malignant thoracic nodules. 18Ffluoromisonidazole (18F-FMISO) is used for imaging tumour hypoxia. Tumour response to treatment is significantly related to the level of tumour oxygenation. Angiogenesis is the process by which new blood vessels are formed in tumours and is involved in tumour growth and metastatic tumour spread and is a therapeutic target. Most clinical studies have focused on targeted integrin PET imaging of which αvβ3 integrin is the most extensively investigated. It is upregulated on activated endothelial cells in association with tumour angiogenesis. Neuroendocrine tumour tracers, particularly 68Ga-DOTA-peptides, have an established role in imaging of carcinoid tumours. Whilst most of these tracers have predominantly been used in the research environment, they offer exciting opportunities for improving staging, characterisation, stratification and response assessment in an era of increased personalised therapy in lung cancer. [ABSTRACT FROM AUTHOR]

Squamous cell carcinoma of the anus (SCCA) is a rare cancer but its incidence is increasing throughout the world, and is particularly high in the human immunodeficiency virus positive (HIV+) population. A multidisciplinary approach is mandatory (involving radiation therapists, medical oncologists, surgeons, radiologists and pathologists). SCCA usually spreads in a loco-regional manner within and outside the anal canal. Lymph node involvement at diagnosis is observed in 30-40% of cases while systemic spread is uncommon with distant extrapelvic metastases recorded in 5-8% at onset, and rates of metastatic progression after primary treatment between 10% and 20%. SCCA is strongly associated with human papilloma virus (HPV, types 16-18) infection. The primary aim of treatment is to achieve cure with loco-regional control and preservation of anal function, with the best possible quality of life. Treatment dramatically differs from adenocarcinomas of the lower rectum. Combinations of 5FU-based chemoradiation and other cytotoxic agents (mitomycin C) have been established as the standard of care, leading to complete tumour regression in 80-90% of patients with locoregional failures in the region of 15%. There is an accepted role for surgical salvage. Assessment and treatment should be carried out in specialised centres treating a high number of patients as early as possible in the clinical diagnosis. To date, the limited evidence from only 6 randomised trials [1,2,3,4,5,6,7], the rarity of the cancer, and the different behaviour/natural history depending on the predominant site of origin, (the anal margin, anal canal or above the dentate line) provide scanty direction for any individual oncologist. Here we aim to provide guidelines which can assist medical, radiation and surgical oncologists in the practical management of this unusual cancer. [ABSTRACT FROM AUTHOR]

Objectives: Objective evaluation of the extent of skeletal marrow involvement in multiple myeloma remains a clinical gap for CT. We aimed to develop a quantitative segmentation pipeline for dual energy CT and to assess whether quantified whole skeleton calcium-subtracted attenuation values correlate with biopsy-derived bone marrow infiltration in multiple myeloma.Methods: Consecutive prospective patients with suspected/established myeloma underwent dual source CT from the skull vertex to proximal tibia. Whole skeleton segmentation was performed for 120 kVp-equivalent images as follows: following Hounsfield unit (HU) thresholding, a Chan-Vese morphological operation was implemented to generate a whole skeleton segmentation mask. This mask was then applied to corresponding whole skeleton material decomposition calcium-subtracted maps, generating whole skeleton HU values. Associations with biopsy-derived bone marrow plasma cell infiltration percentage were assessed with Spearman's rank correlation; significance was at 5%.Results: 21 patients (12 females; median (IQR) 67 (61, 73) years) were included; 16 patients had osteolytic bone lesions; 15 patients underwent bone marrow biopsy. Segmentation and quantification were feasible in all patients. Median (IQR) of the average skeletal calcium-subtracted attenuation was -59.9 HU (-66.3, -51.8HU). There was a positive correlation with bone marrow plasma cell infiltration percentage (Spearman's rho: + 0.79, p < 0.001).Conclusion: Whole skeleton calcium-subtracted attenuation is associated with the degree of bone marrow infiltration by plasma cells, providing an objective measure of marrow involvement with the potential to allow earlier detection of disease. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To determine if there is a difference between contrast enhanced CT texture features from the largest cross-sectional area versus the whole tumor, and its effect on clinical outcome prediction. Methods: Entropy (E) and uniformity (U) were derived for different filter values (1.0–2.5: fine to coarse textures) for the largest primary tumor cross-sectional area and the whole tumor of the staging contrast enhanced CT in 55 patients with primary colorectal cancer. Parameters were compared using non-parametric Wilcoxon test. Kaplan–Meier analysis was performed to determine the relationship between CT texture and 5-year overall survival. Results: E was higher and U lower for the whole tumor indicating greater heterogeneity at all filter levels (1.0–2.5): median (range) for E and U for whole tumor versus largest cross-sectional area of 7.89 (7.43–8.31) versus 7.62 (6.94–8.08) and 0.005 (0.004–0.01) versus 0.006 (0.005–0.01) for filter 1.0; 7.88 (7.22–8.48) versus 7.54 (6.86–8.1) and 0.005 (0.003–0.01) versus 0.007 (0.004–0.01) for filter 1.5; 7.88 (7.17–8.54) versus 7.48 (5.84–8.25) and 0.005 (0.003–0.01) versus 0.007 (0.004–0.02) for filter 2.0; and 7.83 (7.03–8.57) versus 7.42 (5.19–8.26) and 0.005 (0.003–0.01) versus 0.006 (0.004–0.03) for filter 2.5 respectively (p ≤0.001). Kaplan–Meier analysis demonstrated better separation of E and U for whole tumor analysis for 5-year overall survival. Conclusion: Whole tumor analysis appears more representative of tumor heterogeneity. [Copyright &y& Elsevier]

Abstract: Purpose: To assess the feasibility of diffusion tensor imaging (DTI) of desmoid tumours in familial adenomatous polyposis (FAP). Materials and methods: Following ethical approval and informed consent, FAP patients with desmoids underwent DTI. Fractional anisotropy (FA), relative anisotropy (RA) and apparent diffusion coefficient (ADC) were compared to control muscle using Mann–Whitney test; and to tumour site and signal intensity using one way analysis of variance (ANOVA). Imaging was repeated after 1 year. Results: 15 desmoids (6 intra-abdominal; 6 abdominal wall, 3 extra-abdominal; size range: 1.6–22.9cm) were evaluated in 9 patients. DTI was successful in 12/15 desmoid tumours. Median (range) of RA, FA and ADC were 0.23×10−3 mm2/s (0.17–0.26); 0.27×10−3 mm2/s (0.21–0.31); and 1.65×10−3 mm2/s (1.39–1.91) for desmoids, significantly different from muscle: 0.27×10−3 mm2/s (0.23–0.40), 0.32×10−3 mm2/s (0.28–0.46), and 1.45×10−3 mm2/s (0.92–1.63) (p =0.0001, p =0.0001, p =0.0016, respectively). There was no difference in RA, FA or ADC between tumour sites, or signal intensity (p >0.05). One year later, 2 patients had died. Tumour increased in size in 1 patient (+61%). DTI quantification was possible in only 8/13 tumours. FA, RA and ADC were not significantly different from baseline (p =0.77, 0.71 and 0.34, respectively). Conclusions: Assessment of water diffusion has the potential to provide insight into tumour microstructure and is feasible in desmoids. Desmoid tumours demonstrate anisotropy but diffusion is less restricted and less directional than in muscle. [Copyright &y& Elsevier]