Hyung Jin Won

Radiotherapy Plus Transarterial Chemoembolization for Hepatocellular Carcinoma Invading the Portal Vein: Long-Term Patient Outcomes

PURPOSE We have evaluated the clinical outcomes of patients after transarterial chemoembolization (TACE) and 3-dimensional conformal radiotherapy for hepatocellular carcinoma (HCC) with portal vein tumor thrombosis (PVTT). METHODS AND MATERIALS A registry database of 412 patients treated with TACE and three-dimensional conformal radiotherapy for HCC with PVTT between August 2002 and August 2008 were analyzed retrospectively. The radiotherapy volume included the PVTT, with a 2- to 3-cm margin to cover adjacent HCC. Intrahepatic primary HCC was managed by TACE before or after radiotherapy. RESULTS Median patient age was 52 years old, and 88.1% of patients were male. Main or bilateral PVTT was observed in 200 (48.5%) patients. Median radiation dose was 40 Gy (range, 21-60 Gy) delivered in 2- to 5-Gy fractions. We found that 3.6% of patients achieved a complete response and that 24.3% of patients achieved a partial response. The response and progression-free rates of PVTT were 39.6% and 85.6%, respectively. Median patient survival was 10.6 months, and the 1- and 2-year survival rates were 42.5% and 22.8%, respectively. Significant independent variables associated with overall survival included advanced tumor stage, alpha-fetoprotein level, degree of PVTT, and response to radiotherapy. Forty-one patients (10.0%) showed grade 3-4 hepatic toxicity during or 3 months after completion of radiotherapy. Grades 2-3 gastroduodenal complications were observed in 15 patients (3.6%). CONCLUSIONS Radiotherapy is a safe and effective treatment for PVTT in patients with HCC. These results suggested that the combination of TACE and radiotherapy is a treatment option for relieving and/or stabilizing PVTT in patients with advanced HCC.

Radiofrequency Ablation for the Treatment of Primary Intrahepatic Cholangiocarcinoma

OBJECTIVE We present the results of percutaneous radiofrequency ablation (RFA) in patients with unresectable primary intrahepatic cholangiocarcinoma. MATERIALS AND METHODS From 2000 to 2009, 13 patients with 17 primary intrahepatic cholangiocarcinomas underwent RFA at our institution. Intrahepatic cholangiocarcinoma was unresectable because of poor hepatic reserve due to liver cirrhosis in nine patients, extrahepatic extension in two, atrophy of the left hepatic lobe in one, and underlying comorbidities in one. Ten tumors had a diameter of less than 3 cm, five were between 3 and 5 cm, and two were larger than 5 cm. Technical effectiveness was defined as the complete ablation of the tumor, shown by imaging follow-up 1 month later. Local progression-free survival, overall survival periods, and complications after RFA were also evaluated. RESULTS Technical effectiveness of RFA was achieved for 15 of the 17 tumors (88%), all smaller than 5 cm in diameter. Treatment failure occurred in two patients with large tumors (7 and 8 cm). After the 17 RFA sessions, one major complication (6%), a liver abscess, occurred 1 month later. During follow-up (median, 19.5 months; range, 3.3-82.1 months), nine patients died and four remain alive. Median local progression-free survival and overall survival periods were 32.2 and 38.5 months, respectively. The 1-, 3-, and 5-year survival rates were 85%, 51%, and 15%, respectively. CONCLUSION RFA may provide successful local tumor control in patients with primary intrahepatic cholangiocarcinomas of intermediate (3-5 cm) or small (< 3 cm) diameter. RFA for unresectable primary intrahepatic cholangiocarcinoma resulted in a median overall survival period of 38.5 months.

Efficient liver segmentation using a level-set method with optimal detection of the initial liver boundary from level-set speed images

Automatic liver segmentation is difficult because of the wide range of human variations in the shapes of the liver. In addition, nearby organs and tissues have similar intensity distributions to the liver, making the livers boundaries ambiguous. In this study, we propose a fast and accurate liver segmentation method from contrast-enhanced computed tomography (CT) images. We apply the two-step seeded region growing (SRG) onto level-set speed images to define an approximate initial liver boundary. The first SRG efficiently divides a CT image into a set of discrete objects based on the gradient information and connectivity. The second SRG detects the objects belonging to the liver based on a 2.5-dimensional shape propagation, which models the segmented liver boundary of the slice immediately above or below the current slice by points being narrow-band, or local maxima of distance from the boundary. With such optimal estimation of the initial liver boundary, our method decreases the computation time by minimizing level-set propagation, which converges at the optimal position within a fixed iteration number. We utilize level-set speed images that have been generally used for level-set propagation to detect the initial liver boundary with the additional help of computationally inexpensive steps, which improves computational efficiency. Finally, a rolling ball algorithm is applied to refine the liver boundary more accurately. Our method was validated on 20 sets of abdominal CT scans and the results were compared with the manually segmented result. The average absolute volume error was 1.25+/-0.70%. The average processing time for segmenting one slice was 3.35 s, which is over 15 times faster than manual segmentation or the previously proposed technique. Our method could be used for liver transplantation planning, which requires a fast and accurate measurement of liver volume.

Image quality and focal lesion detection on T2‐weighted MR imaging of the liver: Comparison of two high‐resolution free‐breathing imaging techniques with two breath‐hold imaging techniques

To evaluate image quality and accuracy for the detection of focal hepatic lesions depicted on T2‐weighted images obtained with two high‐resolution free‐breathing techniques (navigator‐triggered turbo spin‐echo [TSE] and respiratory‐triggered TSE) and two standard‐resolution breath‐hold techniques (breath‐hold TSE with restore pulse and half‐Fourier acquisition single‐shot TSE [HASTE]).

CT-guided Radiofrequency Ablation for Hepatocellular Carcinomas That Were Undetectable at US: Therapeutic Effectiveness and Safety

PURPOSE To determine the therapeutic effectiveness and safety of computed tomography (CT)-guided radiofrequency (RF) ablation for hepatocelluar carcinomas (HCCs) that were undetectable at ultrasonography (US). MATERIALS AND METHODS CT-guided RF ablation with use of internally cooled electrodes was performed in 66 patients with 97 HCCs (diameter range, 3-39 mm) in 78 sessions. Two radiologists retrospectively evaluated in consensus the presence or absence of local tumor progression as well as the complications at CT performed immediately after RF ablation and at 1-, 3-, 6-, and 12-month follow-up. The relationship between the occurrence of pneumothorax and the electrode length in the lung in patients treated with the transpulmonary approach was statistically evaluated with use of the Mann-Whitney test. RESULTS The technical success rate of CT-guided RF ablation immediately after RF ablation was 97% (94 of 97 HCCs). The primary technique effectiveness rates of complete ablation 1, 3, 6, and 12 months after RF ablation were 97% (94 of 97 HCCs), 94% (91 of 97 HCCs), 84% (81 of 96 HCCs), and 74% (66 of 89 HCCs), respectively. Major complications were observed in six of the 78 treatment sessions (7.7%). In five of these six sessions, pneumothorax developed immediately after RF ablation; the remaining complication was tumor seeding along the electrode tract. Self-limiting pneumothorax was observed in 12 of 38 sessions (32%) in which the transpulmonary approach was used. The electrode length in the lung was not statistically related to the occurrence of pneumothorax (P = .26). CONCLUSIONS For HCCs that are undetectable at US, CT-guided RF ablation is effective and relatively safe.

Gastric schwannomas: radiological features with endoscopic and pathological correlation

AIM To describe the radiological, endoscopic, and pathological findings of gastric schwannomas in 16 patients. MATERIALS AND METHODS The radiological, endoscopic, and pathological findings of 16 surgically proven cases of gastric schwannoma were retrospectively reviewed. All patients underwent computed tomography (CT) and four patients were evaluated with upper gastrointestinal series. Two radiologists reviewed the CT and upper gastrointestinal series images by consensus with regard to tumour size, contour, margin, and growth pattern, the presence or absence of ulcer, cystic change, and the CT enhancement pattern. Endoscopy was performed in eight of these 16 patients. Six patients underwent endoscopic ultrasonography. Pathological specimens were obtained from and reviewed in all 16 patients. Immunohistochemistry was performed for c-kit, CD34, smooth muscle actin, and S-100 protein. RESULTS On radiographic examination, gastric schwannomas appeared as submucosal tumours with the CT features of well-demarcated, homogeneous, and uncommonly ulcerated masses. Endoscopy with endoscopic ultrasonography demonstrated homogeneous, submucosal masses contiguous with the muscularis propria in all six examined cases. On pathological examination, gastric schwannomas appeared as well-circumscribed and homogeneous tumours in the muscularis propria and consisted microscopically of interlacing bundles of spindle cells. Strong positivity for S-100 protein was demonstrated in all 16 cases on immunohistochemistry. CONCLUSION Gastric schwannomas appear as submucosal tumours of the stomach and have well-demarcated and homogeneous features on CT, endoscopic ultrasonography, and gross pathology. Immunohistochemistry consistently reveals positivity for S-100 protein in the tumours.

Combination of transarterial chemoembolization and three-dimensional conformal radiotherapy for hepatocellular carcinoma with inferior vena cava tumor thrombus.

PURPOSE To evaluate the effects of transarterial chemoembolization (TACE) and three-dimensional conformal radiotherapy (CRT) in patients with hepatocellular carcinoma (HCC) and inferior vena cava tumor thrombus (IVCTT). METHODS AND MATERIALS A total of 42 consecutive patients who underwent TACE and CRT (TACE+CRT group) for the treatment of HCC with IVCTT were prospectively enrolled from July 2004 to October 2006. As historical controls, 29 HCC patients with IVCTT who received TACE alone (TACE group) between July 2003 and June 2004 were included. CRT was designed to target only the IVCTT and to deliver a median total dose of 45 Gy (range, 28-50 Gy). RESULTS Most baseline characteristics of the two groups were similar (p > 0.05). The response and progression-free rates of IVCTT were significantly higher in the TACE+CRT group than in the TACE group (42.9% and 71.4% vs. 13.8% and 37.9%, respectively; p < 0.01 for both rates). Overall, patient survival was significantly higher in the TACE+CRT group than in the TACE group (p < 0.01), with a median survival time of 11.7 months and 4.7 months, respectively. Treatment with TACE+CRT (hazard ratio [HR] = 0.38; 95% confidence interval [CI], 0.20-0.71), progression of IVCTT (HR = 4.05; 95% CI, 2.00-8.21), Child-Pugh class B (HR = 3.44; 95% CI, 1.79-6.61), and portal vein invasion (HR = 2.31; 95% CI, 1.19-4.50) were identified as independent predictors of mortality by multivariable analysis. CONCLUSIONS The combination of TACE and CRT is more effective in the control of IVCTT associated with HCC and improves patient survival compared with TACE alone.

MDCT of small-bowel disease: value of 3D imaging.

OBJECTIVE Our objective is to show the various clinical applications of MDCT enterography for evaluating small-bowel disease, with a focus on the added value of 3D imaging. CONCLUSION MDCT and refined 3D imaging processes can offer a full examination of the small bowel as well as powerful information about the bowel and its surrounding structures.

Assessment of Hepatic Function with Gd-EOB-DTPA-Enhanced Hepatic MRI

Assessment of hepatic function is essential in determining the prognosis and clinical management of a patient who has chronic liver disease or undergoes liver surgery. For a patient with locally varying hepatic parenchymal abnormalities, a regional assessment of hepatic function mapped onto hepatic anatomy is clinically more meaningful than conventional global metrics of hepatic function. Of late, hepatic magnetic resonance imaging has been increasingly used because of its superb tissue contrast and delineation of hepatic morphology and underlying abnormalities. The introduction of hepatocyte-specific contrast agents such as Gd-EOB-DTPA allows us to view not only the hepatic anatomy but also assess regional hepatic function. In this article, we review and discuss recently published studies that used Gd-EOB-DTPA-enhanced magnetic resonance imaging to evaluate hepatic function.

Maximum number of target lesions required to measure responses to transarterial chemoembolization using the enhancement criteria in patients with intrahepatic hepatocellular carcinoma

BACKGROUND & AIMS The European Association for the Study of the Liver (EASL) criteria and, more recently, the modified Response Evaluation Criteria in Solid Tumors (mRECIST), have been widely adopted for evaluating responses to locoregional therapies for hepatocellular carcinoma (HCC). We wished to establish the optimum maximum number of target lesions that need to be measured in enhancement estimations. METHODS From a prospective registry in our institution we identified 160 consecutive patients who had at least two measurable HCCs of nodular type exceeding 10mm in diameter, and who initially underwent transarterial chemoembolization (TACE). Intra-patient and inter-method agreement on confirmed response status were evaluated based on a maximum of one, two, or three target lesions selected among the measurable lesions according to size, versus all baseline lesions. RESULTS Per patient analyses showed that the most consistent response distribution under both EASL and mRECIST was obtained using two or three targets versus all measurable lesions. These features were maintained even in analyses of subgroups stratified according to size, distribution, and number of tumors. The kappa values of comparisons between using a maximum of two or three targets versus using all the lesions were near 1.0, significantly higher than those obtained under both criteria using just the largest tumor. Similar conclusions were obtained when either two or three targets were measured. CONCLUSIONS Our data indicate that evaluating the largest two lesions is generally the most useful procedure for measuring TACE responses under both EASL and mRECIST.