Chae Yoon Chon
Yonsei University
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International Journal of Radiation Oncology Biology Physics | 2001
Hee Chul Park; Jinsil Seong; Kwang Hyub Han; Chae Yoon Chon; Young Myoung Moon; Chang Ok Suh
PURPOSE Dose escalation using three-dimensional conformal radiotherapy (3D-CRT) is based on the hypothesis that increasing the dose can enhance tumor control. This study aimed to determine whether a dose-response relationship exists in local radiotherapy for primary hepatocellular carcinoma (HCC). METHODS AND MATERIALS One hundred fifty-eight patients were enrolled in the present study between January 1992 and March 2000. The exclusion criteria included the presence of an extrahepatic metastasis, liver cirrhosis of Child class C, tumors occupying more than two-thirds of the entire liver, and a performance status on the Eastern Cooperative Oncology Group scale of more than 3. Radiotherapy was given to the field, including the tumor, with generous margin using 6- or 10-MV X-rays. The mean radiation dose was 48.2 +/- 7.9 Gy in daily 1.8-Gy fractions. The tumor response was assessed based on diagnostic radiologic examinations, including a computed tomography scan, magnetic resonance imaging, and hepatic artery angiography 4-8 weeks after the completion of treatment. Liver toxicity and gastrointestinal complications were evaluated. RESULTS An objective response was observed in 106 of 158 (67.1%) patients. Statistical analysis revealed that the total dose was the most significant factor associated with the tumor response. The response rates in patients treated with doses <40 Gy, 40-50 Gy, and >50 Gy were 29.2%, 68.6%, and 77.1%, respectively. Survivals at 1 and 2 years after radiotherapy were 41.8% and 19.9%, respectively, with a median survival time of 10 months. The rate of liver toxicity according to the doses <40 Gy, 40-50 Gy, and >50 Gy was 4.2%, 5.9%, and 8.4%, respectively, and the rate of gastrointestinal complications was 4.2%, 9.9%, and 13.2%, respectively. CONCLUSIONS The present study showed the existence of a dose-response relationship in local radiotherapy for primary HCC. Only the radiation dose was a significant factor for predicting an objective response. The results of this study showed that 3D-CRT can theoretically be used for treating primary HCC.
Hepatology | 2011
Kyu Sik Jung; Seung Up Kim; Sang Hoon Ahn; Young Nyun Park; Do Young Kim; Jun Yong Park; Chae Yoon Chon; Eun Hee Choi; Kwang Hyub Han
Liver stiffness measurement (LSM) using FibroScan accurately assesses the degree of liver fibrosis and the risk of hepatocellular carcinoma (HCC) development in patients with chronic hepatitis C. This study investigated the usefulness of LSM as a predictor of HCC development in patients with chronic hepatitis B (CHB). A total of 1,130 patients with non‐biopsy–proven CHB who underwent LSM between May 2005 and December 2007 were enrolled in this prospective study. After LSM was performed, patients attended regular follow‐up as part of a surveillance program for the detection of HCC. The mean age of the patients (767 men, 363 women) was 50.2 years, and the median LSM was 7.7 kPa. Six hundred seventy‐two (59.5%) patients received antiviral treatment before or after enrollment. During the follow‐up period (median, 30.7 months; range, 24.0‐50.9 months), HCC developed in 57 patients (2.0% per 1 person‐year). The 1‐, 2‐, and 3‐year cumulative incidence rates of HCC were 0.80%, 3.26%, and 5.98%, respectively. On multivariate analysis, together with old age, male sex, heavy alcohol consumption (>80 g/day), serum albumin, and hepatitis B e antigen positivity, patients with a higher LSM (>8 kPa) were at a significantly greater risk of HCC development, with the following hazard ratios: 3.07 (95% confidence interval [CI], 1.01‐9.31; P = 0.047) for LSM 8.1‐13 kPa; 4.68 (95% CI, 1.40‐15.64; P = 0.012) for LSM 13.1‐18 kPa; 5.55 (95% CI, 1.53–20.04; P = 0.009) for LSM 18.1‐23 kPa; and 6.60 (95% CI, 1.83‐23.84; P = 0.004) for LSM >23 kPa. Conclusion: Our data suggest that LSM could be a useful predictor of HCC development in patients with CHB. (HEPATOLOGY 2011)
International Journal of Radiation Oncology Biology Physics | 2003
Jinsil Seong; Hee Chul Park; Kwang Hyub Han; Chae Yoon Chon
PURPOSE To analyze the treatment results and prognostic factors affecting survival in patients with unresectable hepatocellular carcinoma treated with local radiotherapy (RT). METHODS AND MATERIALS Between 1992 and 2000, 158 patients with unresectable hepatocellular carcinoma received local RT. Sixty-seven patients had an advanced UICC Stage III lesion and 91 patients had Stage IVA. The mean tumor size was 9.0 +/- 3.0 cm, and liver cirrhosis was present in 142 patients. Local RT was combined with transarterial chemoembolization as primary treatment (107 patients) or as salvage after failure of repeated transarterial chemoembolization (51 patients). The mean radiation dose was 48.2 +/- 7.9 Gy in daily 1.8-Gy fractions. RESULTS The mean follow-up was 21.6 months after diagnosis and 14.6 months after RT. The response rate was 67.1%. The overall survival rate at 2 and 5 years was 30.5% and 9%, respectively, from the time of diagnosis (median survival time 16 months) and 19.9% and 4.7%, respectively, after RT (median survival time 10 months). On univariate analysis, tumor size (p = 0.047), the presence of portal vein thrombosis (p = 0.007), and RT dose (p = 0.001) were significant factors for survival. However, on multivariate analysis, RT dose was the only significant factor (p = 0.01). CONCLUSION Local RT achieved substantial tumor regression and survival. The radiation dose was found to be a significant prognostic factor in the RT of hepatocellular carcinoma. Additional efforts for dose escalation are warranted to improve the treatment results in parallel with better protecting the nontumorous liver.
PLOS ONE | 2012
Young Eun Chon; Eun Hee Choi; Ki Jun Song; Jun Yong Park; Do Young Kim; Kwang Hyub Han; Chae Yoon Chon; Sang Hoon Ahn; Seung Up Kim
Background Transient elastography (TE), a non-invasive tool that measures liver stiffness, has been evaluated in meta-analyses for effectiveness in assessing liver fibrosis in European populations with chronic hepatitis C (CHC). However, these data cannot be extrapolated to populations in Asian countries, where chronic hepatitis B (CHB) is more prevalent. In this study, we performed a meta-analysis to assess the overall performance of TE for assessing liver fibrosis in patients with CHB. Methods Studies from the literature and international conference abstracts which enrolled only patients with CHB or performed a subgroup analysis of such patients were enrolled. Combined effects were calculated using area under the receiver operating characteristic curves (AUROC) and diagnostic accuracy values of each study. Result A total of 18 studies comprising 2,772 patients were analyzed. The mean AUROCs for the diagnosis of significant fibrosis (F2), severe fibrosis (F3), and cirrhosis (F4) were 0.859 (95% confidence interval [CI], 0.857–0.860), 0.887 (95% CI, 0.886–0.887), and 0.929 (95% CI, 0.928–0.929), respectively. The estimated cutoff for F2 was 7.9 (range, 6.1–11.8) kPa, with a sensitivity of 74.3% and specificity of 78.3%. For F3, the cutoff value was determined to be 8.8 (range, 8.1–9.7) kPa, with a sensitivity of 74.0% and specificity of 63.8%. The cutoff value for F4 was 11.7 (range, 7.3–17.5) kPa, with a sensitivity of 84.6% and specificity of 81.5%. Conclusion TE can be performed with good diagnostic accuracy for quantifying liver fibrosis in patients with CHB.
International Journal of Radiation Oncology Biology Physics | 1999
Jinsil Seong; Ki Chang Keum; Kwang Hyub Han; Do Yun Lee; Jong Tae Lee; Chae Yoon Chon; Young Myoung Moon; C.O. Suh; Gwi Eon Kim
PURPOSE The best prognosis in hepatocellular carcinoma (HCC) can be achieved with surgical resection; however, the number of resected cases are limited due to advanced lesions or associated liver disease. The purpose of this study was to investigate the efficacy and toxicity of a prospective trial of combined transcatheter arterial chemoembolization (TACE) and local radiotherapy (RT) in unresectable HCC. METHODS AND MATERIALS Patients with histologically proven unresectable HCC due to either advanced lesions or associated cirrhosis were eligible. From March 1992 to August 1994, 30 patients were entered into this study. TACE was performed with Lipiodol (5 ml) and doxorubicin (Adriamycin ; 50 mg), followed by gelatin sponge particle (Gelfoam) embolization. Local RT was started within 7-10 days following TACE. Mean tumor dose was 44.0+/-9.3 Gy in daily 1.8 Gy fractions. Response was assessed by computerized tomography (CT) scan 4-6 weeks following completion of the treatment and then at 1-3-month intervals. Survival was calculated from the start of TACE using the Kaplan-Meier method. RESULTS An objective response was observed in 19 patients, giving a response rate of 63.3%. Distant metastasis occurred in 10 patients, with 8 in the lung only and 2 in both lung and bone. Survival rates at 1, 2, and 3 years were 67%, 33.3%, and 22.2%, respectively. Median survival was 17 months. There were 6 patients surviving more than 3 years. Toxicity included transient elevation of liver function tests in all patients, fever in 20, thrombocytopenia in 4, and nausea and vomiting in 1. There was no treatment-related death. CONCLUSION Combined TACE and local RT is feasible and tolerable. It gives a 63.3% response rate with median survival of 17 months. We feel that this regimen would be a new promising modality in unresectable HCC. Further study is required to compare the therapeutic efficacy of this regimen to TACE alone.
Hepatology | 2007
Byung Chul Yoo; Ju Hyun Kim; Young-Hwa Chung; Kwan Sik Lee; Seung Woon Paik; Soo Hyung Ryu; Byung Hoon Han; Joon-Yeol Han; Kwan Soo Byun; Mong Cho; Heon-Ju Lee; Tae Hun Kim; S.-G. Cho; Joong-Won Park; Soon-Ho Um; Seong Gyu Hwang; Young Soo Kim; Youn-Jae Lee; Chae Yoon Chon; Byungik Kim; Y. S. Lee; Jin-Mo Yang; Haak Cheoul Kim; Jae Seok Hwang; Sung-Kyu Choi; Y.O. Kweon; Sook-Hyang Jeong; Myung-Seok Lee; Jong-Young Choi; Dae-Ghon Kim
Clevudine is a pyrimidine analogue with potent and sustained antiviral activity against HBV. The present study evaluated the safety and efficacy of 30 mg clevudine once daily for 24 weeks and assessed the durable antiviral response for 24 weeks after cessation of dosing. A total of 243 hepatitis B e antigen (HBeAg)‐positive chronic hepatitis B patients were randomized (3:1) to receive clevudine 30 mg once daily (n = 182) or placebo (n = 61) for 24 weeks. Patients were followed for a further 24 weeks off therapy. Median serum HBV DNA reductions from baseline at week 24 were 5.10 and 0.27 log10 copies/mL in the clevudine and placebo groups, respectively (P < 0.0001). Viral suppression in the clevudine group was sustained off therapy, with 3.73 log10 reduction at week 34 and 2.02 log10 reduction at week 48. At week 24, 59.0% of patients in the clevudine group had undetectable serum HBV DNA levels by Amplicor PCR assay (less than 300 copies/mL). The proportion of patients who achieved normalization of alanine aminotransferase (ALT) levels was 68.2% in the clevudine group and 17.5% in the placebo group at week 24 (P < 0.0001). ALT normalization in the clevudine group was well maintained during post‐treatment follow‐up period. The incidence of adverse events (AEs) was similar between the clevudine group and the placebo group. No resistance to clevudine was detected with 24 weeks of administration of drug. Conclusion: A 24‐week clevudine therapy was well tolerated and showed potent and sustained antiviral effect without evidence of viral resistance during treatment period in HBeAg‐positive chronic hepatitis B. (HEPATOLOGY 2007;45:1172–1178.)
The American Journal of Gastroenterology | 2010
Beom Kyung Kim; Kwang Hyub Han; Jun Yong Park; Sang Hoon Ahn; Ja Kyung Kim; Kwan Sik Lee; Chae Yoon Chon; Do Young Kim
OBJECTIVES:Periodic endoscopic screening for esophageal varices (EVs) and prophylactic treatment for high-risk EVs ((HEVs); (1) medium/large EVs and (2) small EVs with red sign or decompensated cirrhosis) are currently recommended for all cirrhotic patients. However, if a simple, noninvasive test is available, many low-risk patients may safely avoid endoscopy. We developed and validated a new liver stiffness measurement (LSM)-based prediction model for HEVs.METHODS:We prospectively enrolled 280 consecutive B-viral cirrhosis patients from 2005 to 2007 (training set) and 121 from 2007 to 2008 (validation set). All underwent laboratory workups, endoscopy, LSM, and ultrasonography. For detection of HEVs, univariate and multivariate analysis were performed, using χ2-test/t-test and logistic regression, respectively. A prediction model was derived from multivariate predictors.RESULTS:In the training set, 90 had HEVs, and multivariate analysis showed significant differences in LSM, spleen diameter, and platelet count between patients with and without HEVs. We developed LSM-spleen diameter to platelet ratio score (LSPS): LSM × spleen diameter/platelet count. The area under the receiver-operating characteristic curve (AUROC) in the training set was 0.954. At LSPS<3.5, 94.0% negative predictive value (NPV) was provided (184 patients), whereas 94.2% positive predictive value (PPV) was achieved (69 patients) at LSPS>5.5. Overall, the likelihood of HEVs was correctly diagnosed in 253 patients (90.3%). Its predictive values were maintained at similar accuracy in subsequent validation set (AUROC=0.953; 94.7% NPV/93.3% PPV at cutoff 3.5/5.5, respectively).CONCLUSIONS:LSPS is a reliable, noninvasive method for detection of HEVs. Patients with LSPS<3.5 may avoid endoscopy safely, whereas those with LSPS>5.5 should be considered for appropriate prophylactic treatments.
Hepatology | 2011
Jung Min Lee; Sang Hoon Ahn; Hyon Suk Kim; Hana Park; Hye Young Chang; Do Young Kim; Seong Gyu Hwang; Kyu Sung Rim; Chae Yoon Chon; Kwang Hyub Han; Jun Yong Park
Quantitative hepatitis B surface antigen (qHBsAg) and quantitative hepatitis B e antigen (qHBeAg) titers are emerging as useful tools for measuring viral loads and for predicting the virological response (VR) and serological response (SR) to pegylated interferon therapy. However, the clinical utility of these assays in patients taking entecavir (ETV) is largely unknown. Treatment‐naive patients with chronic hepatitis B (CHB) who were taking ETV for 2 years were enrolled. The qHBsAg and qHBeAg levels were serially measured with the Architect assay. From 95 patients, 60.0% of whom were hepatitis B e antigen–positive [HBeAg(+)], 475 samples were analyzed. The median baseline log hepatitis B virus (HBV) DNA, log qHBsAg, and log qHBeAg values were 6.73 copies/mL (4.04‐9.11 copies/mL), 3.58 IU/mL (1.17‐5.10 IU/mL), and 1.71 Paul Ehrlich (PE) IU/mL (−0.64 to 2.63 PE IU/mL), respectively. For the prediction of VR (HBV DNA < 60 copies/mL at 24 months) in HBeAg(+) patients, baseline alanine aminotransferase (P = 0.013), HBV DNA (P = 0.040), and qHBsAg levels (P = 0.033) were significant. For the prediction of VR, the area under the curve for the baseline log qHBsAg level was 0.823 (P < 0.001); a cutoff level of 3.98 IU/mL (9550 IU/mL on a nonlogarithmic scale) yielded the highest predictive value with a sensitivity of 86.8% and a specificity of 78.9%. As for SR (HBeAg loss at 24 months), the reduction of qHBeAg was significantly greater in the SR(+) group versus the SR(−) group. The sensitivity and specificity were 75.0% and 89.8%, respectively, with a decline of 1.00 PE IU/mL at 6 months. With ETV therapy, the correlation between HBV DNA and qHBsAg peaked at 6 months in HBeAg(+) patients. Conclusion: Both qHBsAg and qHBeAg decreased significantly with ETV therapy. The baseline qHBsAg levels and the on‐treatment decline of qHBeAg in HBeAg(+) patients were proven to be highly useful in predicting VR and SR, respectively. The determination of qHBsAg and qHBeAg can help us to select the appropriate strategy for the management of patients with CHB. However, the dynamic interplay between qHBsAg, qHBeAg, and HBV DNA during antiviral therapy remains to be elucidated. (Hepatology 2011;)
Cancer | 2008
Kwang Hyub Han; Jinsil Seong; Ja Kyung Kim; Sang Hoon Ahn; Do Yun Lee; Chae Yoon Chon
Patients with advanced hepatocellular carcinoma (HCC) with portal vein thrombosis (PVT) have a particularly grave prognosis. In the current study, an attempt was made to localize chemoradiation therapy (CCRT) followed by hepatic arterial infusion chemotherapy (HAIC) in patients with locally advanced HCC with PVT and good reserve liver function. The objective of the current study was to evaluate the therapeutic effect of localized CCRT followed by HAIC as a new treatment modality for these patients.
Hepatology | 2007
Byung Chul Yoo; Ju Hyun Kim; Tae Hun Kim; Kwang Cheol Koh; Soon-Ho Um; Young Soo Kim; Kwan Sik Lee; Byung Hoon Han; Chae Yoon Chon; Joon-Yeol Han; Soo Hyung Ryu; Haak Cheoul Kim; Kwan Soo Byun; Seong Gyu Hwang; Byungik Kim; Mong Cho; Kwon Yoo; Heon-Ju Lee; Jae Seok Hwang; Yun Soo Kim; Y. S. Lee; Sung-Kyu Choi; Youn-Jae Lee; Jin-Mo Yang; Joong-Won Park; Myung-Seok Lee; Dae-Ghon Kim; Young-Hwa Chung; S.-G. Cho; Jong-Young Choi
Clevudine is a pyrimidine analog with potent and sustained antiviral activity against HBV. In the present study, we evaluated the safety and efficacy of clevudine 30 mg daily for 24 weeks and assessed the durability of antiviral response for 24 weeks after cessation of dosing in hepatitis B e antigen (HBeAg)‐negative chronic hepatitis B (e‐CHB). We randomized a total of 86 patients (3:1) to receive clevudine 30 mg (n = 63) or placebo (n = 23) daily for 24 weeks. We followed patients for an additional 24 weeks after withdrawal of treatment. The median changes in HBV DNA from baseline were −4.25 and −0.48 log10 copies/mL at week 24 in the clevudine and placebo groups, respectively (P < 0.0001). Viral suppression in the clevudine group was sustained after withdrawal of therapy, with 3.11 log10 reduction at week 48. At week 24 and week 48, 92.1% and 16.4% of patients in the clevudine group had undetectable serum HBV DNA levels by Amplicor PCR assay (<300 copies/mL). The proportion of patients who achieved ALT normalization was 74.6% and 33.3% in the clevudine and placebo groups at week 24, respectively (P = 0.0006). ALT normalization in the clevudine group was well‐maintained during the post‐treatment follow‐up period. The incidence of adverse events was similar in the 2 groups. No resistance to clevudine was detected during treatment. Conclusion: A 24‐week clevudine therapy was well‐tolerated and showed potent and sustained antiviral effect without evidence of viral resistance in e‐CHB patients. However, treatment for longer than 24 weeks would be needed to achieve durable remission. (HEPATOLOGY 2007.)