980
CORRESPONDENCE
HEPATOLOGY, September 2015
Department of Hepatobiliary Surgery The First Affiliated Hospital of Xi’an Jiaotong University College of Medicine Xi’an, China
References 1. El-Serag HB, Kanwal F. Epidemiology of hepatocellular carcinoma in the United States: where are we? Where do we go? HEPATOLOGY 2014;60:1767-1775. 2. Kim HJ, Kim HJ, Lee KE, Kim DJ, Kim SK, Ahn CW, et al. Metabolic significance of nonalcoholic fatty liver disease in nonobese, nondiabetic adults. Arch Intern Med 2004;164:2169-2175. 3. Pang Q, Zhang JY, Song SD, Qu K, Xu XS, Liu SS, et al. Central obesity and nonalcoholic fatty liver disease risk after adjusting for body mass index.
World J Gastroenterol 2014 (In press). Available at: http://www.wjgnet.com/esps/ArticleInPressDetail.aspx?id511230. Accessed August 28, 2014. 4. Schlesinger S, Aleksandrova K, Pischon T, Fedirko V, Jenab M, Trepo E, et al. Abdominal obesity, weight gain during adulthood and risk of liver and biliary tract cancer in a European cohort. Int J Cancer 2013;132:645-657. 5. Ma Y, Yang Y, Wang F, Zhang P, Shi C, Zou Y, et al. Obesity and risk of colorectal cancer: a systematic review of prospective studies. PLoS One 2013;8:e53916.
Author names in bold designate shared co-first authorship. C 2015 by the American Association for the Study of Liver Diseases. Copyright V View this article online at wileyonlinelibrary.com. DOI 10.1002/hep.27668 Potential conflict of interest: Nothing to report.
Randomized, Controlled Trial of Percutaneous Cryoablation Versus Radiofrequency Ablation in Hepatocellular Carcinoma To the Editor: We read the article by Wang et al.1 with great interest regarding percutaneous cryoablation (CRYO) and radiofrequency ablation (RFA) in early hepatocellular carcinoma (HCC) up to 4 cm in diameter. The researchers found that the 3-year tumor progression rate for CRYO is lower than that of RFA with comparable major complications rates. One of the most interesting findings is that patients with relatively large (>3 cm) early HCC showed a significantly lower tumor progression rate in the CRYO group (7.7% vs. 18.2%; P 5 0.041). Current Barcelona Clinic Liver Cancer Group HCC management guidelines do not recommend RFA owing to marked decrease in efficacy when tumor size exceeds 3 cm.2 Theoretically, CRYO therapy has important advantages, including concurrent placement of multiple probes under precisely guiding iceball formation during procedure, which is not available with RFA.3,4 It was a well-designed first randomized trial that reports on these potential benefits, which is consistent with previous nonrandomized studies.5,6 However, the subgroup analyses are still losing their statistical power owing to the small number of patients, which is sensitively influenced by aberrant cases. Additional information, including baseline characteristics and 1-, 3-, and 5-year progression free survival (adjusted by multivariate regression model, if necessary) for each of the >3 cm HCC patient subgroups would be required to reduce perceived bias. Besides, the researchers provided informative data regarding the alternative treatment for those with distant tumor recurrence (110 patients; 30%). Given that combination therapy using transarterial chemoembolization (TACE), sorafenib, and local ablation were associated with patients’ survival,7,8 detailed proportion for postablative treatments with HCC patient (34 cm) subgroups would be helpful to understand why the benefits of tumor progression rate cannot extend the overall survival rates. This information may be supportive for clinicians who consider percutaneous CRYO therapy for relatively large early-stage HCC. MYUNG HAN HYUN, M.D. SANG MI CHUNG, M.D. Department of Internal Medicine Korea University Guro Hospital Korea University Medical Center Seoul, Korea
References 1. Wang C, Wang H, Yang W, Hu K, Xie H, Hu KQ, et al. A multicenter randomized controlled trial of percutaneous cryoablation versus radiofre-
2.
3. 4.
5.
6.
7.
8.
quency ablation in hepatocellular carcinoma. HEPATOLOGY 2014 Oct 6. doi: 10.1002/hep.27548. [Epub ahead of print] Forner A, Reig ME, de Lope CR, Bruix J. Current strategy for staging and treatment: the BCLC update and future prospects. Semin Liver Dis 2010;30:61-74. Ahmed M, Brace CL, Lee FT, Jr., Goldberg SN. Principles of and advances in percutaneous ablation. Radiology 2011;258:351-369. Nair RT, Silverman SG, Tuncali K, Obuchowski NA, vanSonnenberg E, Shankar S. Biochemical and hematologic alterations following percutaneous cryoablation of liver tumors: experience in 48 procedures. Radiology 2008;248:303-311. Bilchik AJ, Wood TF, Allegra D, Tsioulias GJ, Chung M, Rose DM, et al. Cryosurgical ablation and radiofrequency ablation for unresectable hepatic malignant neoplasms: a proposed algorithm. Arch Surg 2000; 135:657-662; discussion, 662-654. Ei S, Hibi T, Tanabe M, Itano O, Shinoda M, Kitago M, et al. Cryoablation provides superior local control of primary hepatocellular carcinomas of >2 cm compared with radiofrequency ablation and microwave coagulation therapy: an underestimated tool in the toolbox. Ann Surg Oncol 2014 Oct 7. doi: 10.1245/s10434-014-4114-7. [Epub ahead of print] Wang C, Lu Y, Wang H, Gao X, Bai W, Qu J, et al. Transarterial chemoembolization with/without cryotherapy is associated with improved clinical outcomes of sorafenib for the treatment of advanced hepatocellular carcinoma. Exp Ther Med 2012;4:188-196. Wang W, Shi J, Xie WF. Transarterial chemoembolization in combination with percutaneous ablation therapy in unresectable hepatocellular carcinoma: a meta-analysis. Liver Int 2010;30:741-749. C 2015 by the American Association for the Study of Liver Diseases. Copyright V View this article online at wileyonlinelibrary.com. DOI 10.1002/hep.27714 Potential conflict of interest: Nothing to report.
Reply: We thank Prof. Hyun for interest in our work. As indicated, radiofrequency ablation (RFA) is considered a curative treatment in patients with cirrhosis and hepatocellular carcinoma (HCC) smaller than 3 cm. With improvements in devices and techniques, many recent studies reported encouraging results, including complete ablation and survival rate of RFA for treating HCC greater than 3 cm.1,2 Our experiences demonstrated that percutaneous cryotherapy could successfully ablate
CORRESPONDENCE
HEPATOLOGY, September 2015
Department of Hepatobiliary Surgery The First Affiliated Hospital of Xi’an Jiaotong University College of Medicine Xi’an, China
References 1. El-Serag HB, Kanwal F. Epidemiology of hepatocellular carcinoma in the United States: where are we? Where do we go? HEPATOLOGY 2014;60:1767-1775. 2. Kim HJ, Kim HJ, Lee KE, Kim DJ, Kim SK, Ahn CW, et al. Metabolic significance of nonalcoholic fatty liver disease in nonobese, nondiabetic adults. Arch Intern Med 2004;164:2169-2175. 3. Pang Q, Zhang JY, Song SD, Qu K, Xu XS, Liu SS, et al. Central obesity and nonalcoholic fatty liver disease risk after adjusting for body mass index.
World J Gastroenterol 2014 (In press). Available at: http://www.wjgnet.com/esps/ArticleInPressDetail.aspx?id511230. Accessed August 28, 2014. 4. Schlesinger S, Aleksandrova K, Pischon T, Fedirko V, Jenab M, Trepo E, et al. Abdominal obesity, weight gain during adulthood and risk of liver and biliary tract cancer in a European cohort. Int J Cancer 2013;132:645-657. 5. Ma Y, Yang Y, Wang F, Zhang P, Shi C, Zou Y, et al. Obesity and risk of colorectal cancer: a systematic review of prospective studies. PLoS One 2013;8:e53916.
Author names in bold designate shared co-first authorship. C 2015 by the American Association for the Study of Liver Diseases. Copyright V View this article online at wileyonlinelibrary.com. DOI 10.1002/hep.27668 Potential conflict of interest: Nothing to report.
Randomized, Controlled Trial of Percutaneous Cryoablation Versus Radiofrequency Ablation in Hepatocellular Carcinoma To the Editor: We read the article by Wang et al.1 with great interest regarding percutaneous cryoablation (CRYO) and radiofrequency ablation (RFA) in early hepatocellular carcinoma (HCC) up to 4 cm in diameter. The researchers found that the 3-year tumor progression rate for CRYO is lower than that of RFA with comparable major complications rates. One of the most interesting findings is that patients with relatively large (>3 cm) early HCC showed a significantly lower tumor progression rate in the CRYO group (7.7% vs. 18.2%; P 5 0.041). Current Barcelona Clinic Liver Cancer Group HCC management guidelines do not recommend RFA owing to marked decrease in efficacy when tumor size exceeds 3 cm.2 Theoretically, CRYO therapy has important advantages, including concurrent placement of multiple probes under precisely guiding iceball formation during procedure, which is not available with RFA.3,4 It was a well-designed first randomized trial that reports on these potential benefits, which is consistent with previous nonrandomized studies.5,6 However, the subgroup analyses are still losing their statistical power owing to the small number of patients, which is sensitively influenced by aberrant cases. Additional information, including baseline characteristics and 1-, 3-, and 5-year progression free survival (adjusted by multivariate regression model, if necessary) for each of the >3 cm HCC patient subgroups would be required to reduce perceived bias. Besides, the researchers provided informative data regarding the alternative treatment for those with distant tumor recurrence (110 patients; 30%). Given that combination therapy using transarterial chemoembolization (TACE), sorafenib, and local ablation were associated with patients’ survival,7,8 detailed proportion for postablative treatments with HCC patient (34 cm) subgroups would be helpful to understand why the benefits of tumor progression rate cannot extend the overall survival rates. This information may be supportive for clinicians who consider percutaneous CRYO therapy for relatively large early-stage HCC. MYUNG HAN HYUN, M.D. SANG MI CHUNG, M.D. Department of Internal Medicine Korea University Guro Hospital Korea University Medical Center Seoul, Korea
References 1. Wang C, Wang H, Yang W, Hu K, Xie H, Hu KQ, et al. A multicenter randomized controlled trial of percutaneous cryoablation versus radiofre-
2.
3. 4.
5.
6.
7.
8.
quency ablation in hepatocellular carcinoma. HEPATOLOGY 2014 Oct 6. doi: 10.1002/hep.27548. [Epub ahead of print] Forner A, Reig ME, de Lope CR, Bruix J. Current strategy for staging and treatment: the BCLC update and future prospects. Semin Liver Dis 2010;30:61-74. Ahmed M, Brace CL, Lee FT, Jr., Goldberg SN. Principles of and advances in percutaneous ablation. Radiology 2011;258:351-369. Nair RT, Silverman SG, Tuncali K, Obuchowski NA, vanSonnenberg E, Shankar S. Biochemical and hematologic alterations following percutaneous cryoablation of liver tumors: experience in 48 procedures. Radiology 2008;248:303-311. Bilchik AJ, Wood TF, Allegra D, Tsioulias GJ, Chung M, Rose DM, et al. Cryosurgical ablation and radiofrequency ablation for unresectable hepatic malignant neoplasms: a proposed algorithm. Arch Surg 2000; 135:657-662; discussion, 662-654. Ei S, Hibi T, Tanabe M, Itano O, Shinoda M, Kitago M, et al. Cryoablation provides superior local control of primary hepatocellular carcinomas of >2 cm compared with radiofrequency ablation and microwave coagulation therapy: an underestimated tool in the toolbox. Ann Surg Oncol 2014 Oct 7. doi: 10.1245/s10434-014-4114-7. [Epub ahead of print] Wang C, Lu Y, Wang H, Gao X, Bai W, Qu J, et al. Transarterial chemoembolization with/without cryotherapy is associated with improved clinical outcomes of sorafenib for the treatment of advanced hepatocellular carcinoma. Exp Ther Med 2012;4:188-196. Wang W, Shi J, Xie WF. Transarterial chemoembolization in combination with percutaneous ablation therapy in unresectable hepatocellular carcinoma: a meta-analysis. Liver Int 2010;30:741-749. C 2015 by the American Association for the Study of Liver Diseases. Copyright V View this article online at wileyonlinelibrary.com. DOI 10.1002/hep.27714 Potential conflict of interest: Nothing to report.
Reply: We thank Prof. Hyun for interest in our work. As indicated, radiofrequency ablation (RFA) is considered a curative treatment in patients with cirrhosis and hepatocellular carcinoma (HCC) smaller than 3 cm. With improvements in devices and techniques, many recent studies reported encouraging results, including complete ablation and survival rate of RFA for treating HCC greater than 3 cm.1,2 Our experiences demonstrated that percutaneous cryotherapy could successfully ablate
