Changing trends in the clinicopathological features, practices and outcomes in the surgical management for cystic lesions of the pancreas and impact of the international guidelines: Single institution experience with 462 cases between 1995-2018.

INTRODUCTION: The impact on clinical practice of the international guidelines including the Sendai Guidelines (SG06) and Fukuoka Guidelines (FG12) on the management of cystic lesions of the pancreas (CLP) has not been well-studied. The primary aim was to examine the changing trends and outcomes in the surgical management of CLP in our institution over time and to determine the impact of these guidelines on our institution practice. METHODS: 462 patients with surgically-treated CLP were retrospectively reviewed and classified under the 2 guidelines. The cohort was divided into 3 time periods: 1998-2006, 2007-2012 and 2013 to 2018. RESULTS: Comparison across the 3 time periods demonstrated significantly increasing frequency of older patients, asymptomatic CLP, male gender, smaller tumor size, elevated Ca 19-9, use of magnetic resonance imaging (MRI) and use of endoscopic ultrasound (EUS) prior to surgery. There was also significantly increasing frequency of adherence to the international guidelines as evidenced by the increasing proportion of HRSG06 and HRFG12 CLP with a corresponding lower proportion of LRSG06 and LRFG12 being resected. This resulted in a significantly higher proportion of resected CLP whereby the final pathology confirmed that a surgery was actually indicated. CONCLUSIONS: Over time, there was increasing adherence to the international guidelines for the selection of patients for surgical resection as evidenced by the significantly increasing proportion of HRSG06 and HRFG06 CLPs undergoing surgery. This was associated with a significantly higher proportion of patients with a definitive indication for surgery. These suggested that over time, there was a continuous improvement in our selection of appropriate CLP for surgical treatment.

Systematic review of the clinical utility and validity of the Sendai and Fukuoka Consensus Guidelines for the management of intraductal papillary mucinous neoplasms of the pancreas.

BACKGROUND: This systematic review was performed to assess the clinical utility of the Sendai Consensus Guidelines (SCG) and Fukuoka Consensus Guidelines (FCG) for intraductal papillary mucinous neoplasm (IPMN). METHODS: A computerized search of PubMed was performed to identify all the studies which evaluated the SCG and FCG in surgically resected, histologically confirmed IPMNs. RESULTS: Ten studies evaluating the FCG, 8 evaluating the SCG and 4 evaluating both guidelines were included. In 14 studies evaluating the FCG, out of a total of 2498 neoplasms, 849 were malignant and 1649 were benign neoplasms. Pooled analysis showed that 751 of 1801 (42%) FCG+ve neoplasms were malignant and 599 neoplasms of 697 (86%) FCG-ve neoplasms were benign. PPV of the high risk and worrisome risk groups were 465/986 (47%) and 239/520 (46%) respectively. In 12 studies evaluating the SCG, 1234 neoplasms were analyzed of which 388 (31%) were malignant and 846 (69%) were benign. Pooled analysis demonstrated that 265 of 802 (33%) SCG+ve neoplasms were malignant and 238 of 266 SCG-ve (90%) neoplasms were benign. CONCLUSION: The FCG had a higher positive predictive value (PPV) compared to the SCG. However, the negative predictive value (NPV) of the FCG was slightly lower than that of the SCG. Malignant and even invasive IPMN may be missed according to both guidelines.

Focal Therapy for Prostate Cancer with In-Bore MR-guided Focused Ultrasound: Two-Year Follow-up of a Phase I Trial-Complications and Functional Outcomes.

Purpose To report the safety profile and 2-year functional outcomes of in-bore magnetic resonance (MR)-guided focused ultrasound on single cancer foci in men with prostate cancer. Materials and Methods Ethics approval was obtained from the centralized institutional review board for this prospective single-arm study, and patients provided informed consent. Patients with untreated low-volume low-grade prostate cancer (clinical stage T2a or lower; Gleason score, 3+3; index tumor ≤10 mm3) underwent MR-guided focused ultrasound between July 2011 and February 2013. All patients underwent robotic transperineal mapping biopsy and multiparametric MR imaging. Only those with a maximum of two lesions smaller than 10 mm at mapping biopsy were included. Target areas were sonicated with real-time MR thermometry monitoring, excluding critical areas from the beam path. Serum prostate-specific antigen (PSA) and Expanded Prostate Index Composite (EPIC) scores were obtained at baseline and at 1, 3, 6, 12, 18, and 24 months and were plotted to observe their trend. Mean EPIC subdomain score changes at each serial time point were compared with the baseline score by using paired t tests (level of significance, P < .007). Repeat transperineal biopsy was performed at 6 and 24 months. Results Fourteen men (mean age, 62.8 years; median PSA level, 8.3 ng/mL) underwent treatment, with 12 men completing 2-year follow-up. A median reduction of PSA level by 2.9 ng/mL was observed at 6 months. Seven men had Clavien-Dindo grade 1-2 complications. There was a slight insignificant deterioration of EPIC urinary symptom score (mean increase of 7.8 points compared with baseline, P = .012) noted at 1 month, but it returned to baseline by 3 months. There was a trend to deterioration in sexual function score (mean decrease, 4.4 points; P = .04 [not significant]) that normalized at 3 months. There was no significant change in EPIC subdomain scores from baseline over the 24 months. At 6-month template biopsy, one man had cancer with a Gleason score greater than 6; at 24 months, three men had cancer with a Gleason score greater than 6. Conclusion MR-guided focused ultrasound is technically feasible for focal prostate ablation and appears to have a favorable early safety and functional profile. Further clinical trials are necessary to establish oncologic efficacy. © RSNA, 2017 Online supplemental material is available for this article.

Single administration of Selective Internal Radiation Therapy versus continuous treatment with sorafeNIB in locally advanced hepatocellular carcinoma (SIRveNIB): study protocol for a phase iii randomized controlled trial.

BACKGROUND: Approximately 20 % of hepatocellular carcinoma (HCC) patients diagnosed in the early stages may benefit from potentially curative ablative therapies such as surgical resection, transplantation or radiofrequency ablation. For patients not eligible for such options, prognosis is poor. Sorafenib and Selective Internal Radiation Therapy (SIRT) are clinically proven treatment options in patients with unresectable HCC, and this study aims to assess overall survival following either SIRT or Sorafenib therapy for locally advanced HCC patients. METHODS: This investigator-initiated, multi-centre, open-label, randomized, controlled trial will enrol 360 patients with locally advanced HCC, as defined by Barcelona Clinic Liver Cancer stage B or stage C, without distant metastases, and which is not amenable to immediate curative treatment. Exclusion criteria include previous systemic therapy, metastatic disease, complete occlusion of the main portal vein, or a Child-Pugh score of >7. Eligible patients will be randomised 1:1 and stratified by centre and presence or absence of portal vein thrombosis to receive either a single administration of SIRT using yttrium-90 resin microspheres (SIR-Spheres®, Sirtex Medical Limited, Sydney, Australia) targeted at HCC in the liver by the trans-arterial route or continuous oral Sorafenib (Nexavar®, Bayer Pharma AG, Berlin, Germany) at a dose of 400 mg twice daily until disease progression, no further response, complete regression or unacceptable toxicity. Patients for both the Sorafenib and SIRT arms will be followed-up every 4 weeks for the first 3 months and 12 weekly thereafter. Overall survival is the primary endpoint, assessed for the intention-to-treat population. Secondary endpoints are tumour response rate, time-to-tumour progression, progression free survival, quality of life and down-staging to receive potentially curative therapy. DISCUSSION: Definitive data comparing these two therapies will help to determine clinical practice in the large group of patients with locally advanced HCC and improve outcomes for such patients. TRIAL REGISTRATION: ClinicalTrials.gov identifier, NCT01135056 , first received 24, May 2010.

Preoperative platelet-to-lymphocyte ratio improves the performance of the international consensus guidelines in predicting malignant pancreatic cystic neoplasms.

INTRODUCTION: To determine if neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) were predictive of malignancy in pancreatic cystic neoplasms (PCN) and if these improved the performance of the international consensus guidelines (ICG) in the initial triage of these patients. METHODS: 318 patients with surgically-treated suspected PCN were retrospectively reviewed. Malignant neoplasms were defined as neoplasms harbouring invasive carcinoma. The optimal cut-off for NLR and PLR were determined by plotting the receiver operating characteristics (ROC) curves of NLR/PLR in predicting malignant PCN and utilizing the Youden index. RESULTS: The optimal NLR and PLR cut-offs were determined to be 3.33 and 205, respectively. Univariate analyses demonstrated that symptomatic PCNs, age, obstructive jaundice, presence of solid component, dilatation of main pancreatic duct ≥10 mm, high NLR and high PLR were predictive of a malignant PCN. Multivariate analyses demonstrated that obstructive jaundice, presence of solid component, MPD ≥10 mm and high PLR but not NLR were independent predictors of a malignant PCN. A high PLR significantly predicted invasive carcinoma in patients classified within the ICG(HR) group. Comparison between the ROC curves of the ICG versus ICG plus high PLR in predicting malignant PCN demonstrated a significant improvement in the accuracy of the ICG when PLR was included [AUC 0.784 (95% CI: 0.740-0.829) vs AUC 0.822 (95% CI: 0.772-0.872) (p = 0.0032)]. CONCLUSIONS: High PLR is an independent predictor of malignancy in PCN. The addition of PLR as a criterion to the ICG improved the accuracy of these guidelines in detecting invasive neoplasms.

Are preoperative blood neutrophil-to-lymphocyte and platelet-to-lymphocyte ratios useful in predicting malignancy in surgically-treated mucin-producing pancreatic cystic neoplasms?

INTRODUCTION: The aim of this study was to determine if neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) were predictive of malignancy in mucin-producing pancreatic cystic neoplasms (MpPCN). METHODS: One hundred and twenty patients with MpPCN were retrospectively reviewed. Malignant neoplasms were defined as neoplasms harbouring invasive carcinoma or high grade dysplasia. A high NLR and PLR were defined as ≥2.551 and ≥208.1, respectively. RESULTS: High NLR was significantly associated with symptomatic tumors, larger tumors, solid component, main-duct IPMN, and Sendai high risk category. High PLR was significantly associated with jaundice and Sendai high risk category. On univariate analyses, symptomatic tumors, jaundice, solid component, dilated pancreatic duct, and both a high NLR and PLR were significant predictors of malignant and invasive MpPCN. On multivariate analyses, solid component and dilated pancreatic duct were independent predictors of malignant and invasive MpPCN. PLR was an independent predictor for invasive MpPCN. When MpPCN were stratified by the Fukuoka and Sendai Guidelines, both a high NLR and PLR were significantly associated with malignant neoplasms within the high risk categories. CONCLUSIONS: PLR is an independent predictor of invasive carcinoma. The addition of PLR as a criterion to the FCG and SCG significantly improved the predictive value of these guidelines in detecting invasive neoplasms.

Are the Sendai and Fukuoka consensus guidelines for cystic mucinous neoplasms of the pancreas useful in the initial triage of all suspected pancreatic cystic neoplasms? A single-institution experience with 317 surgically-treated patients.

BACKGROUND: The Sendai Consensus Guidelines (SCG) were formulated in 2006 and updated in Fukuoka in 2012 (FCG) to guide management of cystic mucinous neoplasms of the pancreas. This study aims to evaluate the clinical utility of the SCG and FCG in the initial triage of all suspected pancreatic cystic neoplasms. STUDY DESIGN: Overall, 317 surgically-treated patients with a suspected pancreatic cystic neoplasm were classified according to the SCG as high risk (HR(SCG)) and low risk (LR(SCG)), and according to the FCG as high risk (HR(FCG)), worrisome (W(FCG)), and low risk (LR(FCG)). Cystic lesions of the pancreas (CLP) were classified as potentially malignant/malignant or benign according to the final pathology. RESULTS: The presence of symptoms, proximal lesions with obstructive jaundice, elevated serum carcinoembryonic antigen/carbohydrate antigen 19-9 (CEA/CA 19-9), size ≥3 cm, presence of solid component, main pancreatic duct dilatation, thickened enhancing walls, and change in ductal caliber with distal atrophy were predictive of a potentially malignant/malignant CLP on univariate analyses. The positive predictive value (PPV) and negative predictive value (NPV) of HR(SCG) and HR(ICG2012) for a potentially malignant/malignant lesion was 67 and 88 %, and 88 and 92.5 %, respectively. There were no malignant lesions in both LR groups but some potentially malignant lesions such as cystic pancreatic neuroendocrine neoplasms with uncertain behavior were classified as LR. CONCLUSION: The updated FCG was superior to the SCG for the initial triage of all suspected pancreatic cystic neoplasms. CLP in the LR(FCG) group can be safely managed conservatively, and those in the HR(FCG) group should undergo resection.

Assessment of tumor necrotic fraction by dynamic contrast-enhanced MRI: a preclinical study of human tumor xenografts with histopathologic correlation.

Contrary to the common notion that tumor necrotic regions are non-enhancing after contrast administration, recent evidence has shown that necrotic regions exhibit delayed and slow uptake of gadolinium tracer on dynamic contrast-enhanced MRI (DCE MRI). The purpose of this study is to explore whether the mapping of tumor voxels with delayed and slow enhancement on DCE MRI can be used to derive estimates of tumor necrotic fraction. Patient-derived tumor xenograft lines of seven human cancers were implanted in 26 mice which were subjected to DCE MRI performed using a spoiled gradient recalled sequence. Gadolinium tracer concentration was estimated using the variable flip angle technique. To identify tumor voxels exhibiting delayed and slow uptake of contrast medium, clustering analysis was performed using a k-means clustering algorithm that classified tumor voxels according to their contrast enhancement patterns. Comparison of the percentage of tumor voxels exhibiting delayed and slow enhancement with the tumor necrotic fraction estimated on histology showed a strong correlation (r = 0.962, p < 0.001). The mapping of tumor regions with delayed and slow contrast uptake on DCE MRI correlated strongly with tumor necrotic fraction, and can potentially serve as a non-invasive imaging surrogate for the in vivo assessment of necrotic fraction.

Correlative assessment of tumor microcirculation using contrast-enhanced perfusion MRI and intravoxel incoherent motion diffusion-weighted MRI: is there a link between them?

The purpose of this study was to correlate intravoxel incoherent motion (IVIM) imaging with classical perfusion-weighted MRI metrics in human gliomas. Parametric images for slow diffusion coefficient (D), fast diffusion coefficient (D*), and fractional perfusion-related volume (f) in patients with high-grade gliomas were generated. Maps of Fp (plasma flow), vp (vascular plasma volume), PS (permeability surface-area product), ve (extravascular, extracellular volume), E (extraction ratio), ke (influx ratio into the interstitium), and tc (vascular transit time) from dynamic contrast-enhanced (DCE) and dynamic susceptibility contrast-enhanced (DSC) MRI were also generated. A region-of-interest analysis on the contralateral healthy white matter and on the tumor areas was performed and the extracted parameter values were tested for any significant differences among tumor grades or any correlations. Only f could be significantly correlated to DSC-derived vp and tc in healthy brain tissue. Concerning the tumor regions, Fp was significantly positively correlated with D* and inversely correlated with f in DSC measurements. The D*, f, and f × D* values in the WHO grade III gliomas were non-significantly different from those in the grade IV gliomas. There was a trend to significant negative correlations between f and PS as well as between f × D* and ke in DCE experiments. Presumably due to different theoretical background, tracer properties and modeling of the tumor vasculature in the IVIM theory, there is no clearly evident link between D*, f and DSC- and DCE-derived metrics.

Use of Natural Language Processing to Infer Sites of Metastatic Disease From Radiology Reports at Scale.

PURPOSE: To evaluate natural language processing (NLP) methods to infer metastatic sites from radiology reports. METHODS: A set of 4,522 computed tomography (CT) reports of 550 patients with 14 types of cancer was used to fine-tune four clinical large language models (LLMs) for multilabel classification of metastatic sites. We also developed an NLP information extraction (IE) system (on the basis of named entity recognition, assertion status detection, and relation extraction) for comparison. Model performances were measured by F1 scores on test and three external validation sets. The best model was used to facilitate analysis of metastatic frequencies in a cohort study of 6,555 patients with 53,838 CT reports. RESULTS: The RadBERT, BioBERT, GatorTron-base, and GatorTron-medium LLMs achieved F1 scores of 0.84, 0.87, 0.89, and 0.91, respectively, on the test set. The IE system performed best, achieving an F1 score of 0.93. F1 scores of the IE system by individual cancer type ranged from 0.89 to 0.96. The IE system attained F1 scores of 0.89, 0.83, and 0.81, respectively, on external validation sets including additional cancer types, positron emission tomography-CT ,and magnetic resonance imaging scans, respectively. In our cohort study, we found that for colorectal cancer, liver-only metastases were higher in de novo stage IV versus recurrent patients (29.7% v 12.2%; P < .001). Conversely, lung-only metastases were more frequent in recurrent versus de novo stage IV patients (17.2% v 7.3%; P < .001). CONCLUSION: We developed an IE system that accurately infers metastatic sites in multiple primary cancers from radiology reports. It has explainable methods and performs better than some clinical LLMs. The inferred metastatic phenotypes could enhance cancer research databases and clinical trial matching, and identify potential patients for oligometastatic interventions.

Primary colorectal cancer: use of kinetic modeling of dynamic contrast-enhanced CT data to predict clinical outcome.

PURPOSE: To compare four different tracer kinetic models for the analysis of dynamic contrast material-enhanced computed tomographic (CT) data with respect to the prediction of 5-year overall survival in primary colorectal cancer. MATERIALS AND METHODS: This study was approved by the ethical review board. Archival dynamic contrast-enhanced CT data from 46 patients with colorectal cancer, obtained as part of a research study, were analyzed retrospectively by using the distributed parameter, conventional compartmental, adiabatic tissue homogeneity, and generalized kinetic models. Blood flow, blood volume, mean transit time (MTT), permeability-surface area product, extraction fraction, extravascular extracellular volume (v(e)), and volume transfer constant (K(trans)) were compared by using the Friedman test, with statistical significance at 5%. Following receiver operating characteristic analysis, parameters of the different kinetic models and tumor stage were compared with respect to overall survival discrimination, with use of Kaplan Meier analysis and a univariate Cox proportional hazard model, with additional cross-validation and permutation testing. RESULTS: Blood flow was lower with the distributed parameter model than with the conventional compartmental and adiabatic tissue homogeneity models (P < .0001), and blood flow values determined with the conventional compartmental and adiabatic tissue homogeneity models were similar. Conversely, MTT was longer with the distributed parameter model than with the conventional compartmental and adiabatic tissue homogeneity models (P < .0001). Blood volume, permeability-surface area product, and v(e) were higher with the conventional compartmental model than with the adiabatic tissue homogeneity, distributed parameter, or generalized kinetic models (P < .0001). The extraction fraction was higher with the distributed parameter model than with the adiabatic tissue homogeneity model. With respect to 5-year overall survival, only the distributed parameter model-derived v(e) was predictive of 5-year overall survival with a threshold value of 15.48 mL/100 mL after cross-validation and permutation testing. CONCLUSION: Parameter values differ significantly between models. Of the models investigated, the distributed parameter model was the best predictor of 5-year overall survival. SUPPLEMENTAL MATERIAL: http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.12120186/-/DC1.

Inferring cancer disease response from radiology reports using large language models with data augmentation and prompting.

OBJECTIVE: To assess large language models on their ability to accurately infer cancer disease response from free-text radiology reports. MATERIALS AND METHODS: We assembled 10 602 computed tomography reports from cancer patients seen at a single institution. All reports were classified into: no evidence of disease, partial response, stable disease, or progressive disease. We applied transformer models, a bidirectional long short-term memory model, a convolutional neural network model, and conventional machine learning methods to this task. Data augmentation using sentence permutation with consistency loss as well as prompt-based fine-tuning were used on the best-performing models. Models were validated on a hold-out test set and an external validation set based on Response Evaluation Criteria in Solid Tumors (RECIST) classifications. RESULTS: The best-performing model was the GatorTron transformer which achieved an accuracy of 0.8916 on the test set and 0.8919 on the RECIST validation set. Data augmentation further improved the accuracy to 0.8976. Prompt-based fine-tuning did not further improve accuracy but was able to reduce the number of training reports to 500 while still achieving good performance. DISCUSSION: These models could be used by researchers to derive progression-free survival in large datasets. It may also serve as a decision support tool by providing clinicians an automated second opinion of disease response. CONCLUSIONS: Large clinical language models demonstrate potential to infer cancer disease response from radiology reports at scale. Data augmentation techniques are useful to further improve performance. Prompt-based fine-tuning can significantly reduce the size of the training dataset.

A Systematic Review and Meta-Analysis of Mapping Biopsy for Primary Extramammary Paget's Disease in Reducing Recurrence Following Surgical Excision.

Objective: To examine the association between the performance of mapping biopsies and surgical outcomes postexcision of extramammary Paget's disease (EMPD). Background: Primary EMPD is a rare entity associated with poorly defined surgical margins and difficult-to-access sites of lesions. Surgical resection with clear margins remains the preferred management method. The use of mapping biopsies might be beneficial, particularly in lowering disease recurrence. Methods: Available literature was reviewed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses methodology before a fixed-effect meta-analysis was performed to identify the presence of a correlation between performing mapping biopsies and positive margins on permanent sections as well as disease-free survival. Additional study results not included in the quantitative assessment were qualitatively assessed and reported. Results: A total of 12 studies were shortlisted for final analysis. 294 patients who underwent mapping biopsies and 48 patients who did not undergo mapping biopsies were included in the assessment. Forest plot analysis revealed a pooled rate ratio of 0.50 (95% CI, 0.32-0.77) in the prevalence of positive margins in patients with mapping biopsies performed as compared to patients without. The pooled rate ratio of the prevalence of disease-free survival in patients with mapping biopsies performed as compared to patients without was 1.38 (95% CI, 1.03-1.84). Qualitative assessment of the remaining selected studies revealed equivocal results. Conclusions: Mapping biopsies are able to improve EMPD surgical excision outcomes but given the rarity of the disease and heterogeneity of mapping biopsy procedures, further confirmation with randomized controlled trials or a larger patient pool is necessary.

Neuroendocrine tumor liver metastases: use of dynamic contrast-enhanced MR imaging to monitor and predict radiolabeled octreotide therapy response.

PURPOSE: To evaluate dynamic contrast-enhanced (DCE) magnetic resonance (MR) imaging for monitoring and assessing treatment response in patients with neuroendocrine liver metastases treated using yttrium 90 ((90)Y)-labeled octreotide ((90)Y-DOTATOC). MATERIALS AND METHODS: The study was approved by the local research and ethics committee and patient informed consent was obtained. Twenty patients with liver metastases from neuroendocrine tumors underwent T1-weighted DCE MR imaging of the liver before and at 2 months after intravenous (90)Y-DOTATOC treatment. Regions of interest were drawn around target lesions, as well as along liver outlines for each patient. A dual-input single-compartment model was used to compute parameters including fractional distribution volume and the arterial flow fraction. Pre- and posttreatment values were compared using Wilcoxon signed rank test. Treatment response was defined as showing a greater than 50% reduction in the nadir chromogranin A level within the 1st year after treatment. Pretreatment values of responders and nonresponders were compared using the Mann-Whitney test. A two-tailed P value of .008 or less, which accounts for multiple testing, was considered to indicate a significant difference. RESULTS: In responders, tumor and whole liver distribution volume significantly increased after treatment (median tumor distribution volume, 0.182 vs 0.244; median whole liver distribution volume, 0.175 vs 0.207; P = .008). The pretreatment whole liver distribution volume was significantly lower in responders (median, 0.175 vs 0.248; P = .003), while pretreatment tumor arterial flow fraction was significantly higher in responders (median, 1.000 vs 0.7 ± 1, P = .006). CONCLUSION: DCE MR imaging may be used to monitor the effects of peptide receptor radiolabeled targeted therapy in patients with neuroendocrine tumors liver metastases; a lower pretreatment distribution volume and high arterial flow fraction was associated with a better response to treatment.

Prospective Comparison of the Performance of MRI Versus CT in the Detection and Evaluation of Peritoneal Surface Malignancies.

Background: The performance of MRI versus CT in the detection and evaluation of peritoneal surface malignancies (PSM) remains unclear in the current literature. Our study is the first prospective study in an Asian center comparing the two imaging modalities, validated against intra-operative findings. Methods: A total of 36 patients with PSM eligible for CRS-HIPEC underwent both MRI and CT scans up to 6 weeks before the operation. The scans were assessed for the presence and distribution of PSM and scored using the peritoneal cancer index (PCI), which were compared against PCI determined at surgery. Results: Both MRI and CT were 100% sensitive and specific in detecting the overall presence of PSM. Across all peritoneal regions, the sensitivity and specificity for PSM detection was 49.1% and 93.0% for MRI, compared to 47.8% and 95.1% for CT (p = 0.76). MRI was more sensitive than CT for small bowel disease, although the difference did not reach statistical significance. Comparing PCI on imaging with intra-operative PCI, the mean difference was found to be −3.4 ± 5.4 (p < 0.01) for MRI, and −3.9 ± 4.1 (p < 0.01) for CT. The correlation between imaging and intra-operative PCI was poor, with a concordance coefficient of 0.76 and 0.79 for MRI and CT, respectively. Within individual peritoneal regions, there was also poor agreement between imaging and intra-operative PCI for both modalities, other than in regions 1 and 3. Conclusion: MRI and CT are comparable in the detection and evaluation of PSM. While sensitive in the overall detection of PSM, they are likely to underestimate the true disease burden.

A comparative study of dynamic contrast-enhanced MRI parameters as biomarkers for anti-angiogenic drug therapy.

The aim of the present study was to compare three tracer kinetics methods for the analysis of dynamic contrast-enhanced (DCE) MRI data, namely the generalized kinetics model, the distributed-parameter model and the initial area under the tumor tracer curve (IAUC) method, in a Phase I study of an anti-angiogenic drug ABT -869; and to explore their utility as biomarkers. Twenty-eight patients with a range of tumors formed the study population. DCE MRI performed at baseline and 2 weeks post-treatment was analyzed using all three methods, yielding percentage changes for various tracer kinetics parameters. Correlation analyzes were performed between these parameters and in relation to drug exposure. The association of these parameters with time-to-progression was examined using receiver-operating characteristic and Kaplan-Meier curves. Significant correlation with drug exposure was found for the following parameters: normalized IAUC (IAUC(norm)), fractional interstitial volume v(e), fractional intravascular volume v(1) and permeability PS. However, only v(e) and PS were effective in predicting late progression. A decrease in v(e) of more than 1.7% and a decrease in PS of more than 25.1% observed at 2 weeks post-treatment could be associated with late progression. All three tracer kinetics methods have biomarker potential for assessing the effects of anti-angiogenic therapy.

Fundamentals of tracer kinetics for dynamic contrast-enhanced MRI.

Tracer kinetic methods employed for quantitative analysis of dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) share common roots with earlier tracer studies involving arterial-venous sampling and other dynamic imaging modalities. This article reviews the essential foundation concepts and principles in tracer kinetics that are relevant to DCE MRI, including the notions of impulse response and convolution, which are central to the analysis of DCE MRI data. We further examine the formulation and solutions of various compartmental models frequently used in the literature. Topics of recent interest in the processing of DCE MRI data, such as the account of water exchange and the use of reference tissue methods to obviate the measurement of an arterial input, are also discussed. Although the primary focus of this review is on the tracer models and methods for T(1) -weighted DCE MRI, some of these concepts and methods are also applicable for analysis of dynamic susceptibility contrast-enhanced MRI data.

Deconvolution assessment of splenic and splanchnic contributions to portal venous blood flow in liver cirrhosis.

PURPOSE: To devise a noninvasive imaging method for resolving the relative contribution of splenic and splanchnic blood flow to portal venous flow and derive quantitative estimates for parameters pertaining to splenic and portal hemodynamics. METHODS: Tracer concentration-time curves of the aorta, portal vein, and spleen can be extracted from dynamic contrast-enhanced (DCE) CT or MR images. A combination of two tracer analysis approaches, namely arterial-venous sampling and residual tracer deconvolution, is proposed to model these concentration-time curves and derive hemodynamic parameters pertaining to splenic and portal circulation. Clinical feasibility of the proposed method was explored using DCE CT datasets of eight cirrhotic patients. Monte Carlo simulations were performed to evaluate the confidence of the parameter estimates. RESULTS: Portal blood flow was estimated to be 763.8 +/- 438.1 ml/min in cirrhotic patients and the splenic contribution was found to be elevated (0.75 +/- 0.22). Estimates of splenic blood flow (582 +/- 420 ml/min) and transit time (15.3 +/- 10.1 s) in cirrhotic patients were consistent with reported values obtained using duplex Doppler ultrasound and dynamic scintigraphy, respectively. CONCLUSIONS: This study shows the feasibility of noninvasive assessment of splenic and portal hemodynamic parameters by DCE imaging using a combination of tracer kinetics modeling techniques.

Dynamic Contrast-Enhanced Magnetic Resonance Imaging as Imaging Biomarker for Vascular Normalization Effect of Infigratinib in High-FGFR-Expressing Hepatocellular Carcinoma Xenografts.

PURPOSE: Overexpression of fibroblast growth factor receptor (FGFR) contributes to tumorigenesis, metastasis, and poor prognosis of hepatocellular carcinoma (HCC). Infigratinib-a pan-FGFR inhibitor-potently suppresses the growth of high-FGFR-expressing HCCs in part via alteration of the tumor microenvironment and vessel normalization. In this study, we aim to assess the utility of dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) as a non-invasive imaging technique to detect microenvironment changes associated with infigratinib and sorafenib treatment in high-FGFR-expressing HCC xenografts. PROCEDURES: Serial DCE-MRIs were performed on 12 nude mice bearing high-FGFR-expressing patient-derived HCC xenografts to quantify tumor microenvironment pre- (day 0) and post-treatment (days 3, 6, 9, and 15) of vehicle, sorafenib, and infigratinib. DCE-MRI data were analyzed using extended generalized kinetic model and two-compartment distributed parameter model. After treatment, immunohistochemistry stains were performed on the harvested tumors to confirm DCE-MRI findings. RESULTS: By treatment day 15, infigratinib induced tumor regression (70 % volume reduction from baseline) while sorafenib induced relative growth arrest (185 % volume increase from baseline versus 694 % volume increase from baseline of control). DCE-MRI analysis revealed different changes in microcirculatory parameters upon exposure to sorafenib versus infigratinib. While sorafenib induced microenvironment changes similar to those of rapidly growing tumors, such as a decrease in blood flow (F), fractional intravascular volume (vp), and permeability surface area product (PS), infigratinib induced the exact opposite changes as early as day 3 after treatment: increase in F, vp, and PS. CONCLUSIONS: Our study demonstrated that DCE-MRI is a reliable non-invasive imaging technique to monitor tumor microcirculatory response to FGFR inhibition and VEGF inhibition in high-FGFR-expressing HCC xenografts. Furthermore, the microcirculatory changes from FGFR inhibition manifested early upon treatment initiation and were reliably detected by DCE-MRI, creating possibilities of combinatorial therapy for synergistic effect.

Radioembolisation with Y90-resin microspheres followed by nivolumab for advanced hepatocellular carcinoma (CA 209-678): a single arm, single centre, phase 2 trial.

BACKGROUND: Therapeutic synergism between radiotherapy and immune checkpoint blockade has been observed in preclinical models of hepatocellular carcinoma. We aimed to study the safety and efficacy of sequential radioembolisation with yttrium-90-resin microspheres (Y90-radioembolisation) followed by nivolumab in patients with advanced hepatocellular carcinoma. METHODS: Patients with Child-Pugh A cirrhosis and advanced hepatocellular carcinoma not suitable for curative surgery were treated with Y90-radioembolisation followed by intravenous nivolumab 240 mg 21 days after Y90-radioembolisation and every 2 weeks thereafter. The primary endpoint, assessed in the per-protocol population, was the objective response rate, determined by RECIST version 1.1, defined as the proportion of patients with a confirmed complete or partial response observed for lesions both within and outside the Y90-radioembolisation field. This study is registered with ClinicalTrials.gov, NCT03033446 and has been completed. FINDINGS: 40 patients were enrolled, of whom 36 received Y90-radioembolisation followed by nivolumab. One (3%) patient had a complete response and ten (28%) had a partial response; the objective response rate was 30·6% (95% CI 16·4-48·1). The most common treatment-related adverse events of any grade were pruritus (18 [50%] of 36 patients) and maculopapular rash (13 [36%]). Two (6%) patients experienced grade 3-4 treatment-related adverse events: one patient had a grade 3 increase in alanine aminotransferase levels, grade 3 bilirubin increase, and grade 4 increase in aspartate aminotransferase levels, while the other had a grade 3 maculopapular rash. Five (14%) patients had a treatment-related serious adverse event (Steven-Johnson syndrome, hepatitis E infection, fever, liver abscesses, and ascites). INTERPRETATION: Y90-radioembolisation followed by nivolumab resulted in an encouraging objective response rate in patients with advanced hepatocellular carcinoma, although the activity observed was not as high as the study was powered for. This strategy should be further evaluated in patients with Barcelona Clinic Liver Clinic (BCLC) stage B hepatocellular carcinoma that is ineligible or refractory to transarterial chemoembolisation and patients with BCLC C disease without extrahepatic spread. FUNDING: National Medical Research Council Singapore, Bristol-Myers Squibb, Sirtex.