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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 (v p ), and permeability surface area product (PS), infigratinib induced the exact opposite changes as early as day 3 after treatment: increase in F, v p , 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.

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.

Purpose: There is a need for methods which enable precise correlation of histologic sections with in vivo prostate images. Such methods would allow direct comparison between imaging features and functional or histopathological heterogeneity of tumors. Correlation would be particularly useful for validating the accuracy of imaging modalities, developing imaging techniques, assessing image-guided therapy, etc. An optimum prostate slicing method for accurate correlation between the histopathological and medical imaging planes in terms of section angle, thickness and level was sought., Methods: Literature review (51 references from 1986-2009 were cited) was done on the various sectioning apparatus or techniques used to slice the prostate specimen for accurate correlation between histopathological data and medical imaging. Technology evaluation was performed with review and discussion of various methods used to section other organs and their possible applications for sectioning prostatectomy specimens., Results: No consensus has been achieved on how the prostate should be dissected to achieve a good correlation. Various customized sectioning instruments and techniques working with different mechanism are used in different research institutes to improve the correlation. Some of the methods have convincingly shown significant potential for improving image-specimen correlation. However, the semisolid consistent property of prostate tissue and the lack of identifiable landmarks remain challenges to be overcome, especially for fresh prostate sectioning and microtomy without external fiducials., Conclusions: A standardized optimum protocol to dissect prostatectomy specimens is needed for the validation of medical imaging modalities by histologic correlation. These standards can enhance disease management by improving the comparability between different modalities.

The in vivo assessment of physiological processes associated with microcirculation in the head and neck tissue by means of perfusion computed tomography is widely used in the management of patients with head and neck tumors. However, there is no systematic consideration of the total acquisition duration and placement of the scans. A simulation study for optimizing perfusion studies of extracranial head and neck tumors, with considerations of reducing radiation dose while maintaining accuracy of the perfusion parameters, is demonstrated here. The suggested that dual-phase optimized protocols may provide reliable estimations of the permeability surface area product as well as blood flow and volume without additional radiation burden and serious patient discomfort. These optimized protocols can potentially be useful in the clinical setting of examining patients with extracranial head and neck tumors.

Purpose: Hepatocellular carcinoma (HCC) displays a characteristic hypervascularity and depends on angiogenesis for tumor growth, which thus provides a potential target for therapeutic approaches to HCC. In this study, through the use of combined micro-positron emission tomography (PET)/computed tomography (CT), we investigate if such a combined targeting of vascular endothelial growth factor (VEGF) activity and expression might retard HCC growth in an orthotopic intrahepatic xenograft model., Procedures: Xenograft models were created by intraportal vein injection of HepG2 cell suspensions in severe combined immunodeficient mice. The mice were then treated with (1) rapamycin (RAPA), a mammalian target of rapamycin pathway inhibitor; (2) bevazicumab (BEV), a VEGF monoclonal antibody; and (3) a RAPA/BEV combination., Results: Assessment of HCC progression using CT with Omnipaque and PET with 2-deoxy-2-(F-18)-fluoro-D: -glucose showed that mice treated with RAPA/BEV had the lowest standardized uptake values (SUVs). At week 2, mice treated with RAPA/BEV, RAPA, and BEV all showed a marked decrease in the SUV(max) readings with the greatest drop being observed in the RAPA/BEV group (1.33 + 0.26, 1.81 + 0.2, 2.05 + 0.4 vs. vehicle control 2.11 + 0.53)., Conclusions: Our results, supported by micro-PET/CT, suggest that RAPA/BEV represents a potential novel antiangiogenic therapy for the treatment of HCC.

Ultrasound is a universal guidance tool for many medical procedures, whereas it is of poor image quality and resolution. Merging high-contrast image information from other image modalities enhances the guidance capability of ultrasound. However, few registration methods work well for it. In this paper we present a surface-to-image registration technique for mono- or multimodal medical data concerning ultrasound. This approach is able to automatically register the object surface to its counterpart in image volume. Three similarity measurements are investigated in the rigid registration experiments of the pubic arch in transrectal ultrasound images. It shown that the selection of the similarity function is related to the ultrasound characteristics of the object to be registered.

A patient with advanced and chemotherapy-refractory nodal marginal zone B-cell lymphoma was given a course of chimeric CD 20 monoclonal antibody Rituximab. Partial response was observed without any major toxicities. Retreatment with Rituximab for disease progression six months after the first course led to partial remission. Adjuvant radiotherapy was given for the residual disease and, currently, patient's disease remains stable eight months after the second course of Rituximab. This case demonstrates the therapeutic efficacy and feasibility of retreatment with Rituximab for relapsed or refractory low grade lymphoma.