Comparison of biannual ultrasonography and annual non-contrast liver magnetic resonance imaging as surveillance tools for hepatocellular carcinoma in patients with liver cirrhosis (MAGNUS-HCC): a study protocol

Background

Ultrasonography (US) is recommended as a standard surveillance tool for patients with a high risk of developing hepatocellular carcinoma (HCC). However, the low sensitivity of US for small HCC can lead to surveillance failure, resulting in advanced stage tumor presentations. For the early detection of HCC in high-risk patients and to improve survival and prognosis, a new efficient imaging tool with a high sensitivity for HCC detection is needed. The purpose of this study is to evaluate and compare the feasibility and efficacy of non-contrast magnetic resonance imaging (MRI) with US as a surveillance tool for HCC in patients with liver cirrhosis.

Methods

MAGNUS-HCC is a prospective, multicenter clinical trial with a crossover design for a single arm of patients. This study was approved by six Institutional Review Boards, and informed consent was obtained from all participants. All patients will undergo liver US every 6 months and non-contrast liver MRI every 12 months during a follow-up period of 3 years. If a focal liver lesion suspected of harboring HCC is detected, dynamic liver computed tomography (CT) will be performed to confirm the diagnosis. After the last surveillance round, patients without suspicion of HCC or who are not diagnosed with HCC will be evaluated with a dynamic liver CT to exclude false-negative findings. The primary endpoint is to compare the rate of detection of HCC by US examinations performed at 6-month intervals with that of yearly non-contrast liver MRI studies during a 3-year follow-up. The secondary endpoint is the survival of the patients who developed HCC within the 3-year follow-up period.

Discussion

MAGNUS-HCC is the first study to compare the feasibility of non-contrast MRI with US as a surveillance tool for the detection of HCC in high-risk patients. We anticipate that the evidence presented in this study will establish the efficacy of non-contrast MRI as a surveillance tool for HCC in high-risk patients.

Trial registration

The date of trial registration (NCT02551250) in this study was September 15, 2015, and follow-up is still ongoing.

Biomarker for the Prediction of Major Adverse Cardiac Events in Patients with Non-ST-Segment Elevation Myocardial Infarction

N-terminal pro-brain natriuretic peptide (NT-proBNP) is a well-known biomarker for the diagnosis and prognosis of heart failure, and is directly associated with myocardial dysfunction. We evaluated the prognostic value of NT-proBNP for major adverse cardiac events (MACEs) among patients with non-ST-segment elevation myocardial infarction (NSTEMI) from the Korea Acute Myocardial Infarction Registry during their mid-term follow-up period. In this paper, we analyzed NT-proBNP according to various MACE and level of NT-proBNP. We used multivariate logistic regression to determine the risk factors according to MACE type and NT-proBNP levels, and to identify the cutoff value for each MACE by using the receiver operating characteristic (ROC) curve. NT-proBNP was a significant variable among cardiac deaths (p = 0.016), myocardial infarction (p = 0.000), and coronary artery bypass grafting (CABG) (p = 0.000) in patients with MACE compared with those without MACE. Two-vessel coronary artery disease (CAD) (p = 0.037) and the maximum creatinine kinase (max-CK) (p = 0.031) produced significant results in repeat percutaneous coronary intervention. The area under the ROC curve was found to be statistically significant for cardiac death and CABG. NT-proBNP is a useful predictor for 12-month MACEs among patients with NSTEMI and in those with heart failure. We propose that a new index incorporating NT-proBNP, max-CK, and CAD vessel will be useful as a prognostic indicator of MACEs in the future.

Single nucleotide polymorphisms at miR-146a/196a2 and their primary ovarian insufficiency-related target gene regulation in granulosa cells

MicroRNAs post-transcriptionally regulate gene expression in animals and plants. The aim of this study was to identify new target genes for microRNA polymorphisms (miR-146aC>G and miR-196a2T>C) in primary ovarian insufficiency (POI). We cloned and transfected miR-146aC>G and miR-196a2T>C into human granulosa cells and used microarrays and qPCR-arrays to examine the changes in the messenger RNA expression profile. We show miR-146aC>G and miR-196a2T>C change the mRNA expression patterns in granulosa cell. In each case, mRNAs were up or down-regulated after treatments with miR-146a C or G and miR-196a2 T or C. We found that miR-146a led to a significantly altered regulation of the mRNA levels of FOXO3, FOXL2 and CCND2 compared to controls. We also found that the polymorphisms of miR-146a led to a significantly altered regulation of CCND2 and FOXO3. Our results suggest that miR-146aC>G and miR-196a2T>C can regulate the levels of many of their target transcripts. In addition, specific target genes of miR-146aC>G polymorphisms may be involved in granulosa cell regulation.

Effects of anatomical characteristics as factors in abdominal aortic aneurysm rupture: CT aortography analysis

The aim of this study was to analyze the anatomical characteristics of patients with ruptured abdominal aortic aneurysms (AAAs) using computed tomography (CT) aortography in order to determine the risk factors for rupture.We retrospectively reviewed the CT aortography findings and medical records of patients with ruptured AAAs who underwent CT aortography between February 2002 and December 2014. Age, sex, blood pressure at the time of rupture, treatment methods used for the ruptured AAAs, and treatment outcomes were analyzed. Statistical analyses were performed to determine the association between the maximum aneurysm diameter, which is considered the standard predictor of aneurysm rupture, and anatomical characteristics such as proximal neck diameter, angle between the suprarenal aorta and the aneurysm neck (α angle), angle between the aneurysm neck and aneurysm sac (β angle), and angles between the abdominal aorta and both iliac arteries.Data were reviewed for a total of 36 patients. The mean maximum diameter of AAAs was 76.84 ± 21.08 mm. Multivariate analysis adjusted for age and sex indicated statistical correlations between the α and β angles and maximum aneurysm diameter and between the β angle and iliac artery involvement.Our results suggest that the tortuosity of the aorta tends to be associated with the diameter of AAAs and iliac artery involvement. Investigation of the anatomical characteristics of individual patients using CT aortography is expected to aid in predicting the risk of AAA rupture.

Prediction of KRAS Mutation in Rectal Cancer Using MRI

AIM

The purpose of the study was to investigate imaging predictors of Kirsten-ras (KRAS) mutations using magnetic resonance imaging (MRI) in patients with rectal cancer.

PATIENTS AND METHODS

A total of 275 patients with rectal cancer were enrolled. They underwent pretreatment rectal MRI, and then KRAS mutation evaluation following surgery. Two reviewers assessed diverse MRI findings associated with rectal cancer.

RESULTS

KRAS mutations were detected in 107 (38.9%). KRAS mutations were associated with N stage, gross tumor pattern, axial length of the tumor, and the ratio of the axial to the longitudinal dimensions of the tumor (p=0.0064, p<0.0001, p=0.0003 and p=0.0090). The frequency of KRAS mutations was higher in N2 stage (53.70%), and polypoid tumors (59.09%). Tumors with KRAS mutations exhibited a longer axial length, as well as a larger ratio of the axial to the longitudinal dimensions.

CONCLUSION

KRAS mutations were associated with N stage, a polypoid pattern, axial tumor length, and the ratio of the axial to the longitudinal dimensions of the tumor.

Safety issues and updates under MR environments

Magnetic resonance (MR) imaging is a useful imaging tool with superior soft tissue contrast for diagnostic evaluation. The MR environments poses unique risks to patients and employees differently from ionizing radiation exposure originated from computed tomography and plain x-ray films. The technology associated with MR system has evolved continuously since its introduction in the late 1970s. MR systems have advanced with static magnetic fields, faster and stronger gradient magnetic fields and more powerful radiofrequency transmission coils. Higher field strengths of MR offers greater signal to noise capability and better spatial resolution, resulting in better visualization of anatomic detail, with a reduction in scan time. With the rapid evolution of technology associated with MR, we encounter new MR-related circumstances and unexpected dangerous conditions. A comprehensive update of our knowledge about MR safety is necessary to prevent MR-related accidents and to ensure safety for patients and staff associated with MR. This review presents an overview about MR-related safety issues and updates.

MRI traceability of superparamagnetic iron oxide nanoparticle-embedded chitosan microspheres as an embolic material in rabbit uterus

PURPOSE

We aimed to compare polyvinyl alcohol (PVA) particles with calibrated superparamagnetic iron oxide (SPIO) nanoparticle-loaded chitosan microspheres in a rabbit model, specifically regarding the relative distribution of embolic agents within the uterus based on magnetic resonance imaging (MRI) and pathological evaluation.

METHODS

Twelve New Zealand white rabbits underwent uterine artery embolization using either standard PVA particles (45-150 µm or 350-500 µm) or calibrated SPIO-embedded chitosan microspheres (45-150 µm or 300-500 µm). MRI and histopathological findings were compared one week after embolization.

RESULTS

Calibrated SPIO-loaded chitosan microspheres 45-150 µm in size were detected on T2-weighted images. On histological analysis, calibrated SPIO-embedded chitosan microspheres were found in both myometrium and endometrium, whereas PVA particles were found only in the perimyometrium or extrauterine fat pads. A proportional relationship was noted between the calibrated SPIO-embedded chitosan microsphere size and the size of the occluded artery.

CONCLUSION

Calibrated SPIO-embedded chitosan microspheres induced greater segmental arterial occlusion than PVA particles and showed great potential as a new embolic material. SPIO-embedded chitosan microspheres can be used to follow distribution of embolic particles through MRI studies.

Safety and Efficacy of Percutaneous Biliary Covered Stent Placement in Patients with Malignant Biliary Hilar Obstruction; Correlation with Liver Function

PURPOSE

To estimate the safety and efficacy of percutaneous ePTFE-covered biliary stent placement and the relationship between underlying liver function and stent patency in patients with malignant hilar obstruction.

MATERIALS AND METHODS

From March 2012 to June 2015, 41 patients [22 females, 19 males; mean age 69.8 (range 34-94) years] with malignant biliary obstruction underwent percutaneous biliary stent placement (31 patients with unilateral, 10 patients with bilateral side-by-side). Cumulative patient survival and stent patency rate curves were derived using the Kaplan-Meier method. A Cox model was used to explore the relationship between liver function and patient survival, and also biliary stent patency. Pearson correlation coefficient was used to analyze the relationship between patient survival and stent patency.

RESULTS

Technical success rate was 100 % and clinical success rate was 95 %. During follow-up, four complications occurred (two bilomas and two cases of acute cholecystitis) and were treated successfully with percutaneous drainage. No other complication occurred. Mean serum bilirubin level was 11.34 ± 7.35 mg/dL before drainage and 5.00 ± 4.83 mg/dL 2 weeks after stent placement. The median patent survival duration was 147 days (95 % CI, 69.6-224.4 days). The median stent patency duration was 101 days (95 % CI, 70.0-132.0 days). The cumulative stent patency rates at 1, 3, 6, and 12 months were 97, 57.6, 30.3, and 17.0 %, respectively. Child-Pugh score was correlated significantly with patient survival (P = 0.011) and stent patency (P = 0.007). MELD score was correlated significantly with stent patency (P = 0.044). There was a correlation between patient survival and stent patency (r = 0.778, P < 0.001).

CONCLUSION

Percutaneous placement of ePTFE-covered biliary stent was a safe and an effective method for malignant biliary obstruction. Underlying liver function seemed to be one of the important factors affecting patient survival and stent patency, and stent patency showed statistically significant correlation with patient survival.

Proposal reviewer recommendation system based on big data for a national research management institute

National research management organizations need to ensure that research proposals are reviewed fairly and efficiently, which requires the selection of suitable reviewers. In particular, reviewing research proposals in a particular area necessitates the selection of a group with the most reasonable standard for recommending an expert in that area. In this study, we develop an automatic matching system that matches a research proposal with a reviewer who can evaluate it most effectively, using keywords with fuzzy weights based on databases in the corresponding field of research. All functions that we developed were based on the MapReduce framework created by Hadoop, which was verified to enhance matching performance and ensure expandability. This enabled us to select suitable researchers from existing research projects, papers and research reviewer databases. Our system can influence the operation of the national research management system and contribute to academic development.

Efficiency of Non-Contrast-Enhanced Liver Imaging Sequences Added to Initial Rectal MRI in Rectal Cancer Patients

Purpose

The purpose of this study was to estimate the value of addition of liver imaging to initial rectal magnetic resonance imaging (MRI) for detection of liver metastasis and evaluate imaging predictors of a high risk of liver metastasis on rectal MRI.

Methods

We enrolled 144 patients who from October 2010 to May 2013 underwent rectal MRI with T2-weighted imaging (T2WI) and diffusion-weighted imaging (DWI) (b values = 50, 500, and 900 s/mm²) of the liver and abdominopelvic computed tomography (APCT) for the initial staging of rectal cancer. Two reviewers scored the possibility of liver metastasis on different sets of liver images (T2WI, DWI, and combined T2WI and DWI) and APCT and reached a conclusion by consensus for different analytic results. Imaging features from rectal MRI were also analyzed. The diagnostic performances of CT and an additional liver scan to detect liver metastasis were compared. Multivariate logistic regression to determine independent predictors of liver metastasis among rectal MRI features and tumor markers was performed. This retrospective study was approved by the Institutional Review Board, and the requirement for informed consent was waived.

Results

All sets of liver images were more effective than APCT for detecting liver metastasis, and DWI was the most effective. Perivascular stranding and anal sphincter invasion were statistically significant for liver metastasis (p = 0.0077 and p = 0.0471), while extramural vascular invasion based on MRI (mrEMVI) was marginally significant (p = 0.0534).

Conclusion

The addition of non-contrast-enhanced liver imaging, particularly DWI, to initial rectal MRI in rectal cancer patients could facilitate detection of liver metastasis without APCT. Perivascular stranding, anal sphincter invasion, and mrEMVI detected on rectal MRI were important imaging predictors of liver metastasis.

Inter-observer variability of response evaluation criteria for hepatocellular carcinoma treated with chemoembolization

BACKGROUND

Data comparing EASL and mRECIST criteria for response evaluation in treatment of hepatocellular carcinoma are rare. We evaluated inter-observer variability by these two response evaluation criteria in treatment-naïve patients undergoing chemoembolization.

METHODS

For 133 patients undergoing chemoembolization, two radiologists independently measured sum of bi-dimensional and uni-dimensional diameters at baseline using both EASL criteria and mRECIST, and their changes on first follow-up for up to 5 target lesions.

RESULTS

Concordance correlation coefficients for sum of bi-dimensional and uni-dimensional diameters at baseline between two observers were 0.992 and 0.988, respectively. However, those for their changes on follow-up were 0.865 and 0.877, respectively. Similarly, mean differences in sum of bi-dimensional and uni-dimensional diameters at baseline between two observers were small; -0.455 and 0.079 cm, respectively. However, mean differences in changes (%) in sum of bi-dimensional and uni-dimensional diameters on first follow-up between observers increased by -9.715% and -9.320%, respectively. Regarding tumour numbers, kappa-value between observers was 0.942. For treatment response (complete or partial response, stable disease and progression), kappa-value was 0.941 by both criteria. When only up to two target lesions were assessed, kappa-value was 1.000 by both criteria.

CONCLUSIONS

Inter-observer agreements using both response evaluation criteria were excellent, especially when up to two targets were assessed.

MRI Findings and Prediction of Time to Progression of Patients with Hepatocellular Carcinoma Treated with Drug-eluting Bead Transcatheter Arterial Chemoembolization

The purpose of this study was to investigate the utility of MRI findings after drug-eluting beads (DEB) - transcatheter arterial chemoembolization (TACE) for hepatocellular carcinoma in predicting time to progression (TTP). This study included 48 patients with 60 lesions who underwent liver MRI within 3 months after DEB-TACE. MRI was assessed for arterial enhancement pattern, late washout, arterioportal shunt, signal intensity on T2-weighted image, intratumoral septa, enhancing tissue on subtraction images, and treatment response. Cox-regression analysis was performed to identify independent factors to predict TTP. TTP was calculated using the Kaplan-Meier method with the log-rank test. Per lesion, 30 achieved complete remission, 22 had a partial response, and the remaining 8 lesions displayed stable disease on MRI. Arterial enhancement pattern, washout and enhancing tissue on subtraction images from MRI were associated with viable tumor on the last follow-up computerized tomography. Arterial enhancement, washout and enhancing tissue on subtraction images were significant predictors of TTP, but only enhancing tissue on subtraction images remained a significant predictor of TTP (P=0.018) in the multivariate analysis. TTP was longer in the group without enhancing tissue on subtraction images compared to the group with enhancing tissue (601 days vs. 287 days, P<0.001). Enhancing tissue on subtraction images from MRI after DEB-TACE is predictive for longer TTP.

Prognostic role of magnetic resonance imaging vs. computed tomography for hepatocellular carcinoma undergoing chemoembolization

BACKGROUND & AIMS

Computed tomography (CT) and magnetic resonance imaging (MRI) play important roles in diagnosis and staging of hepatocellular carcinoma (HCC). However, prognostic roles of radiological characteristics are not yet determined.

METHODS

Eighty-eight patients treated with chemoembolization were analysed. Radiological parameters at baseline were assessed in all patients using both dynamic CT and MRI. Treatment responses were assessed using modified RECIST 4 weeks after the first chemoembolization.

RESULTS

Gross vascular invasion (GVI), bile duct invasion, irregular tumour margin (ITM), peripheral ragged enhancement (PRE) and satellite nodules on CT or MRI were associated with non-response (stable disease or progression) after chemoembolization respectively (all P ≤ 0.05). GVI, ITM and PRE on CT or MRI were also independently associated with poor overall survival (OS) respectively (all P ≤ 0.05). Using these results, a prognostic scoring system for CT and MRI were developed; 0, absence of all three features (GVI, ITM and PRE); 1, presence of one feature; 2, presence of two features; and 3, presence of three features. After adjusting tumour size, tumour number and alpha-foetoprotein level, both CT and MRI scores were independently associated with OS (both P < 0.001). Patients with CT or MRI score ≥2 had a worse OS than those with score <2 (adjusted hazard ratios, 3.837 and 2.938 respectively). MRI-specific parameters such as signal intensity on T2- or T1-weighted images, fat signal or hyperintensity on diffusion-weighted images did not have prognostic value (all P > 0.05).

CONCLUSIONS

Radiological parameters by CT and MRI may be useful in biological characterization of tumours and prognostification for HCC treated with chemoembolization.

Complete response at first chemoembolization is still the most robust predictor for favorable outcome in hepatocellular carcinoma

BACKGROUNDS & AIMS

The aim of this study is to evaluate the prognostic significances of not only the initial and the best response during repeated transarterial chemoembolization (TACE) for hepatocellular carcinoma (HCC), but if eligible, also the time point of achieving treatment responses.

METHODS

Three hundred and fourteen treatment-naïve patients with well-preserved liver function undergoing TACE were recruited. Treatment responses were assessed using modified Response Evaluation Criteria in Solid Tumors. Overall survival (OS) was analyzed using Kaplan-Meier methods, and Cox regression analysis was performed for multivariate analysis.

RESULTS

After adjusting other variables, objective response (complete response [CR] and partial response [PR]) as the initial response (adjusted hazard ratio [HR] 0.410) and the best response (adjusted HR 0.335) had independent prognostic significances for OS, respectively (both p < 0.001). Objective responders as the initial response had the longest OS, followed by patients who subsequently achieved objective response after at least two sessions and those who did not achieve objective response during treatment course eventually (52.6, 27.0, and 10.8 months, respectively; log-rank test, p < 0.001). Likewise, patients with CR as the initial response had the longest OS, followed by those who subsequently achieved CR after at least two sessions and those who achieved PR as the best response (70.2, 40.6, and 23.0 months, respectively; log-rank test, p < 0.001). Large (>5 cm) and multiple (⩾ 4) tumors were independently associated with failure to achieve CR after the initial TACE (both p < 0.05).

CONCLUSION

Both the initial and the best response predicts OS effectively. However, achievement of treatment response at an early time point is still the most robust predictor for favorable outcomes.

Added value of arterial enhancement fraction color maps for the characterization of small hepatic low-attenuating lesions in patients with colorectal cancer

OBJECTIVE

To assess the added value of arterial enhancement fraction (AEF) color maps for the differentiation of small metastases from hepatic benign lesions.

SUBJECTS AND METHODS

We retrospectively analyzed 46 patients with colorectal cancer who underwent multiphasic liver CT imaging and had low-attenuating liver lesions smaller than 3 cm (123 total lesions; metastasis: benign = 32:91). AEF color maps of the liver were created from multiphasic liver CT images using dedicated software. Two radiologists independently reviewed multiphasic CT image sets alone and in combination with image sets with AEF color maps using a five-point scale. The additional diagnostic value of the color maps was assessed by means of receiver-operating characteristic (ROC) analysis.

RESULTS

The area under the ROC curve (Az) increased when multiphasic CT images were combined with AEF color map analysis as compared with evaluation based only on multiphasic CT images (from 0.698 to 0.897 for reader 1, and from 0.825 to 0.945 for reader 2; P < 0.001 and 0.002, respectively). The increase Az was especially significant for lesions less than 1 cm (from 0.702 to 0.888 for reader 1, and from 0.768 to 0.958 for reader 2; P = 0.001 and P = 0.001, respectively). The mean AEF of tumor-adjacent parenchyma (35.07 ± 27.2) was significantly higher than that of tumor-free liver parenchyma (27.3 ± 20.6) (P = 0.04).

CONCLUSIONS

AEF color mapping can improve the diagnostic performance for small hepatic metastases from colorectal cancer and may allow for the elimination of additional examinations.

Rapid genotyping of Plasmodium vivax Pvs25 and Pv38 genes by using mismatch specific endonuclease

Mismatch specific endonuclease (MSE) method was used to detect natural polymorphisms in Pvs25 and Pv38 genes of Plasmodium vivax. Eighty seven patients with P. vivax were recruited in the Republic of Korea (ROK). Pvs25 and Pv38 genes were amplified by polymerase chain reaction (PCR), and the PCR amplicons were mixed with reference DNA sequences. Following the denaturation and gradual annealing, the product mixtures were cleaved by the MSE. Heteroduplex types were readily detected by gel electrophoresis, where extra bands with shorter sizes would appear from the cleavage. After MSE cleavage of 657- bp product from Pvs25 mixtures, three genotypes were detected, while Pv38 mixtures with 1220-bp products presented two genotypes in ROK isolates. After the MSE cleavage, the mismatched samples of Pvs25 and Pv38 were completely sequenced, and the results were in complete agreement with the MSE analyses. In conclusion, genotyping of Pvs25 and Pv38 with MSE cleavage could be a potential method for the high-throughput screening of the large field samples.

Diffusion and perfusion MRI prediction of progression-free survival in patients with hepatocellular carcinoma treated with concurrent chemoradiotherapy

PURPOSE

To assess whether MR perfusion and diffusion parameters taken before concurrent chemoradiotherapy (CCRT) are useful imaging biomarkers for predicting progression-free survival (PFS) in patients with hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

Twenty patients with locally advanced HCC who had no treatment before CCRT underwent dynamic contrast-enhanced (DCE) and diffusion-weighted MRI. Mean values of the volume transfer constant (K(trans) ), reflex constant (Kep ), extravascular extracellular volume fraction (Ve ) and the apparent diffusion coefficient (ADC) were estimated on a region of interest. The best cutoff value for each factor was assessed to differentiate between patients who had PFS shorter or longer than the median PFS. Patients were dichotomized in terms of the cutoff value. The survival outcome of the two groups and the predictive ability of each factor on PFS were evaluated.

RESULTS

Median time to PFS was 179 days. The best cutoff values for ADC, K(trans) , Kep , and Ve was 1.008 × 10(-3) mm(2) s(-1) , 0.108 min(-1) , 0.570 min(-1) , and 0.298%. Patients with higher ADC had significantly longer PFS than those with lower ADC(P < 0.0001).

CONCLUSION

The ADC of HCC acquired before CCRT correlated with PFS and was valuable in the prediction of the clinical outcome of HCC treated with CCRT.

¹⁸F-FDG PET metabolic parameters and MRI perfusion and diffusion parameters in hepatocellular carcinoma: a preliminary study

Objectives

Glucose metabolism, perfusion, and water diffusion may have a relationship or affect each other in the same tumor. The understanding of their relationship could expand the knowledge of tumor characteristics and contribute to the field of oncologic imaging. The purpose of this study was to evaluate the relationships between metabolism, vasculature and cellularity of advanced hepatocellular carcinoma (HCC), using multimodality imaging such as ¹⁸F-FDG positron emission tomography (PET), dynamic contrast enhanced (DCE)-MRI, and diffusion weighted imaging(DWI).

Materials and Methods

Twenty-one patients with advanced HCC underwent ¹⁸F-FDG PET, DCE-MRI, and DWI before treatment. Maximum standard uptake values (SUV_max) from ¹⁸F-FDG-PET, variables of the volume transfer constant (K^trans) from DCE-MRI and apparent diffusion coefficient (ADC) from DWI were obtained for the tumor and their relationships were examined by Spearman’s correlation analysis. The influence of portal vein thrombosis on SUV_max and variables of K^trans and ADC was evaluated by Mann-Whitney test.

Results

SUV_max showed significant negative correlation with K^trans_max (ρ = −0.622, p = 0.002). However, variables of ADC showed no relationship with variables of K^trans or SUV_max (p>0.05). Whether portal vein thrombosis was present or not did not influence the SUV _max and variables of ADC and K^trans (p>0.05).

Conclusion

In this study, SUV was shown to be correlated with K_trans in advanced HCCs; the higher the glucose metabolism a tumor had, the lower the perfusion it had, which might help in guiding target therapy.

Number of target lesions for EASL and modified RECIST to predict survivals in hepatocellular carcinoma treated with chemoembolization

PURPOSES

To date, most studies about the optimal number of target lesions for enhancement criteria for hepatocellular carcinoma (HCC) have focused on cross-sectional analyses of concordance. We investigated the optimal number of target lesions for European Association for the Study of the Liver (EASL) and modified Response Evaluation Criteria in Solid Tumors (mRECIST) guidelines in predicting overall survival (OS).

EXPERIMENTAL DESIGN

We analyzed 254 consecutive treatment-naïve patients with HCC having at least 2 measurable target lesions undergoing transarterial chemoembolization. Kappa values for intermethod agreement of treatment responses were calculated for comparisons between use of maximum of 1, 2, 3, 4, or 5 targets versus use of all target lesions. Prognostic values of radiologic assessments according to number of target lesions for predicting OS were expressed as C-index.

RESULTS

By EASL and mRECIST guidelines, κ values between responses assessing the longest 2, 3, 4, or 5 targets and assessing all targets were 0.924, 0.977, 1.000, or 1.000 and 0.907, 0.959, 1.000, or 1.000, respectively, whereas those between responses assessing only one target and assessing all target lesions were 0.723 and 0.666, respectively. C-index when measuring the longest 1, 2, 3, 4, 5, and all targets was similar, ranging from 0.739 to 0.749 for EASL criteria and from 0.750 to 0.759 for mRECIST. From Cox regression analyses, radiologic response from each calculation method showed independently significant effects on OS for both guidelines, regardless of number of target lesions.

CONCLUSIONS

Prognostic values for predicting OS were similar regardless of number of target lesions. Assessing the 2 largest targets rather than only 1 index lesion could be recommended considering high concordances from cross-sectional analyses.

Comparison of breathhold, navigator-triggered, and free-breathing diffusion-weighted MRI for focal hepatic lesions

PURPOSE

To compare the breathhold, navigator-triggered, and free-breathing techniques in diffusion-weighted magnetic resonance imaging (MRI) for the evaluation of focal liver lesions on a 3.0T system.

MATERIALS AND METHODS

Fifty-two patients (36 men, 16 women; mean age, 56.4 years) with focal liver lesions underwent breathhold, navigator-triggered, and free-breathing diffusion-weighted imaging (DWI) of the liver on a 3.0 Tesla (T) system. All sequences were performed with b values of 50 and 800 s/mm(2) and identical parameters except for signal averages (two for navigator-triggered, one for breathhold, and four for free-breathing) and repetition time (3389 ms for navigator-triggered, 1500 ms for breathhold, and 4400 ms for free-breathing). A total of 74 lesions (50 malignant, 24 benign) were evaluated. The signal-to-noise ratios (SNR) of the liver and lesions, contrast-to-noise ratios (CNR) of each lesion, and ADC values of the liver and lesions were compared for each DWI sequence. The detection sensitivity and characterization accuracy were also compared.

RESULTS

The SNRs of the liver and lesions were significantly lower for breathhold DWI than for non-breathhold DWI (navigator-triggered and free-breathing DWI) for all b values. The CNRs of the lesions were also significantly lower for breathhold DWI than for non-breathhold DWI. The ADC values of the liver and focal lesions measured using the three DWI techniques were not significantly different and showed good correlation. For lesion detection and characterization, there were no significant differences between breathhold and non-breathhold DWI.

CONCLUSION

Both breathhold and non-breathhold DWI are comparable for the detection or characterization of focal liver lesions at 3.0T; however, non-breathhold DWI provides higher SNR and CNR than breathhold DWI. In addition, although free-breathing and navigator-triggered DWI sequences show similar performance for 3.0T liver imaging, free-breathing DWI is more time efficient than navigator-triggered DWI.

Robot-assisted spleen-preserving distal pancreatectomy: a single surgeon's experiences and proposal of clinical application

BACKGROUND

Advanced and delicate laparoscopic techniques are usually required for safe and successful laparoscopic spleen-preserving distal pancreatectomy. The unique characteristics of robotic surgical system are thought to be useful for this minimally invasive procedure.

METHODS

From September 2007 to May 2011, patients who underwent robot-assisted, spleen-preserving, distal pancreatectomy for benign and borderline malignant tumors of the pancreas were retrospectively reviewed. Perioperative clinicopathologic surgical outcomes were evaluated.

RESULTS

Twenty-two patients were attempted for robot-assisted, spleen-preserving, distal pancreatectomy, and in 21 patients (95.5 %), the spleen was saved either by splenic vessels conservation (SVC; n = 17, 81 %) or by splenic vessels sacrifice (SVS; n = 4, 19 %). Seven patients were male and 15 were female with a mean age of 43.2 ± 15.2 years. Pathologic diagnosis included MCT in five patients, SCT in five, SPT in four, IPMT in three, NET in three, and other benign conditions in two. The mean operation time was 398.9 ± 166.3 min, but it gradually decreased as experiences were accumulated (Rsq = 0.223, p = 0.023). Intraoperative blood loss was 361.3 ± 360.1 ml, and intraoperative transfusion was required in four patients (18.1 %). A soft diet was given for 1.2 ± 0.4 days, and the length of hospital stay was 7.0 ± 2.4 days postoperatively. Clinically relevant pancreatic fistula was noted in two patients (9.1 %) but was successfully managed conservatively. Most patients (87.5 %) showed patency in conserved both splenic vessels, and only two patients (12.5 %) had partially or completely obliterated in splenic veins in the SVC-SpDP group. Partially impaired splenic perfusion was observed in one patient in the SVS-SpDP group. The perfusion defect area decreased without any clinical symptom after 4 months.

CONCLUSIONS

The robotic surgical system is thought to be beneficial for improving the spleen-preservation rate in laparoscopic distal pancreatectomy. Robot-assisted approach can be chosen for patients who require spleen-preserving distal pancreatectomy.

A case report on 30-week premature twin babies with congenital myotonic dystrophy conceived by in vitro fertilization

Congenital myotonic dystrophy type 1 (DM1) presents severe generalized weakness, hypotonia, and respiratory compromise after delivery with high mortality and poor prognosis. We presented a congenital DM1 of premature twins in the 30th week of gestation. These twins were conceived by in vitro fertilization (IVF). Both babies presented apnea and hypotonia and had characteristic facial appearance. They were diagnosed DM1 by genetic method. They were complicated by chylothorax and expired at 100 and 215 days of age, respectively. Mother was diagnosed DM1 during the evaluation of babies. This is the first report on congenital DM1 which accompanied the chylothorax. More investigation on the association with chylothorax and congenital DM1 is recommended. With a case of severe neonatal hypotonia, congenital DM1 should be differentiated in any gestational age. Finally, since DM1 is a cause of infertility, we should consider DM1 in infertility clinic with detailed history and physical examination.

Prospective comparison of prognostic values of modified Response Evaluation Criteria in Solid Tumours with European Association for the Study of the Liver criteria in hepatocellular carcinoma following chemoembolisation

BACKGROUNDS

European Association for the Study of the Liver (EASL) and modified Response Evaluation Criteria in Solid Tumours (mRECIST) guidelines, which measure changes in arterialised hepatocellular carcinoma (HCC), differ in terms of number of target lesions (all versus ≤2) and calculation method (bidimensional versus unidimensional). We compared prognostic values of mRECIST for predicting overall survival (OS) with reference to EASL criteria in treatment-naïve HCC undergoing trans-arterial chemoembolisation (TACE).

METHODS

The ability to predict OS during longitudinal follow-up was expressed as C-index, and a sample size of 292 patients was required to validate its equivalence between each criteria. Treatment responses were assessed using both guidelines 4weeks after the first TACE, using dynamic computed tomography or magnetic resonance imaging. Kaplan-Meier and Cox regression analyses were used to explore differences in OS between responders (complete or partial) and non-responders (stable or progressive disease), defined by each method.

RESULTS

C-index for EASL and mRECIST guidelines was 0.753 and 0.759, respectively, demonstrating equivalence between two methods. Differences in median OS between responders and non-responders were statistically significant for both EASL (30.1 versus 18.7 months, p<0.001) and mRECIST (33.8 versus 17.1 months, p<0.001) guidelines. In addition to radiological response, α-fetoprotein (p<0.001), tumour number (p<0.001) and tumour size (p=0.048) were significant predictors of OS. In multivariate analysis, radiological criteria, tumour number and α-fetoprotein were identified as independent predictors (all p<0.05).

CONCLUSION

mRECIST, a simpler method, provided prognostic values for predicting OS equivalent to EASL criteria in patients with HCC undergoing TACE as an initial treatment modality.

Hyperintense HCC on hepatobiliary phase images of gadoxetic acid-enhanced MRI: correlation with clinical and pathological features

PURPOSE

To retrospectively determine whether the hyperintense hepatocellular carcinomas (HCCs) seen on the hepatobiliary phase of gadoxetic acid-enhanced MR imaging (EOB-MRI) might have different histologic characteristics from usual hypointense HCCs.

MATERIALS AND METHODS

Two hundred three surgically proven HCCs from 192 patients who underwent preoperative EOB-MRI were analyzed. The demographic and histologic characteristics of hyperintense HCCs were compared with usual hypointense HCCs by using the t-test or Fisher's exact test.

RESULTS

By visual assessment, 18 (8.8%) tumors were classified as hyperintense HCCs. Patients with hyperintense HCC were significantly (p<0.05) older (60.1 vs. 55.2 years) than those with hypointense HCCs. Hyperintense HCCs showed significantly lower rate of microvascular invasion (27.8% vs. 53.5%) and significantly higher rate of peliosis (61.1% vs. 30.8%). Hyperintense HCCs were more frequently expanding type, and none showed infiltrative type or scirrhous histologic pattern.

CONCLUSIONS

Hyperintense HCCs seem to have clinical and histologic features that might be related with more favorable outcomes.