SEE EDITORIAL ON PAGE 436 PATIENTS AND METHODS

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1 Interferon Beta Prevents Recurrence of Hepatocellular Carcinoma After Complete Resection or Ablation of the Primary Tumor A Prospective Randomized Study of Hepatitis C Virus Related Liver Cancer KENJI IKEDA, YASUJI ARASE, SATOSHI SAITOH, MASAHIRO KOBAYASHI, YOSHIYUKI SUZUKI, FUMITAKA SUZUKI, AKIHITO TSUBOTA, KAZUAKI CHAYAMA, NAOYA MURASHIMA, AND HIROMITSU KUMADA SEE EDITORIAL ON PAGE 436 Because hepatocellular carcinoma often recurs after surgical resection or ethanol injection therapy, we conducted a prospective randomized controlled trial of interferon (IFN) in patients with chronic liver disease caused by hepatitis C virus (HCV). Twenty eligible patients with cirrhosis were randomized into two groups: 10 patients treated with 6 million units of natural IFN- twice a week for 36 months and 10 patients without IFN therapy. One patient within the treatment group discontinued interferon therapy after 19 months of treatment because of a mild degree of retinopathy. None of the patients in either group lost HCV-RNA until the end of the observation. Although 7 (70.0%) of 10 patients in the nontreatment group showed tumor recurrence, only 1 (10.0%) of 10 patients with IFN therapy developed tumor recurrence during a median observation period of 25.0 months. Cumulative recurrence rates of the treated and untreated groups were 0% and 62.5% at the end of the first year, and 0% and 100% at the second year, respectively (log-rank test, P.0004). In conclusion, intermittent administration of IFN suppressed tumor recurrence after treatment with surgery or ethanol injection in patients with HCV-related chronic liver disease. (HEPATOLOGY 2000;32: ) Until recently, chronic infection with hepatitis C virus (HCV) has been causally associated with hepatocellular carcinoma (HCC). 1-4 In 2 cohort studies of Japanese patients with cirrhosis from Tokyo 5 and Osaka, 6 the cumulative appearance rates of hepatocellular carcinoma at 3, 5, 10, and 15 years were, respectively, 12.5%, 19.4%, 44.3%, and 58.2%. Abbreviations: HCV, hepatitis C virus; HCC, hepatocellular carcinoma; IFN, interferon; AST, aspartate transaminase; ALT, alanine transaminase. From the Department of Gastroenterology, Toranomon Hospital, Tokyo, Japan, and Okinaka Memorial Institute for Medical Research, Tokyo, Japan. Received March 3, 2000; accepted May 25, Address reprint requests to: Kenji Ikeda, M.D., Department of Gastroenterology, Toranomon Hospital, 2-2-2, Toranomon, Minato-ku, Tokyo, , Japan. ikedakenji@tora. .ne.jp; fax: (81) Copyright 2000 by the American Association for the Study of Liver Diseases /00/ $3.00/0 doi: /jhep According to our estimation of the carcinogenesis rates in untreated patients with chronic hepatitis C, 7 the 5-, 10-, and 15-year rates were 4.8%, 13.6%, and 26.0%, respectively. Because the recurrence rate of HCC is very high even after potentially curative therapies with surgical resection or ethanol injection therapy, suppression of recurrence is of great importance for prolonging the life of patients with HCV-related liver disease. This high recurrence rate, after curative therapy, was explained by intrahepatic metastasis in the early stage of HCC or by multicentric carcinogenesis in the setting of chronic viral hepatitis or cirrhosis Interferon (IFN) is effective in eliminating HCV and in reducing serum alanine transaminase in some patients with chronic hepatitis C A Japanese trial of IFN therapy on patients with HCV-related cirrhosis showed that the use of IFN reduced the incidence of HCC in those patients who became negative for HCV RNA in their serum. 16 We elucidated the anticarcinogenic activity of interferon also in patients with chronic hepatitis C, by comparing a large number of untreated patients. 17 Some investigators 18,19 showed that IFN acted as an anticancer agent in the treatment of HCC in vivo and in vitro. However, the effect of IFN in preventing recurrence of HCV-associated HCC in optimally treated patients has not been reported. To elucidate whether IFN suppresses the recurrence rate of HCC, we performed a prospective randomized controlled trial of long-term administration of IFN in patients with HCVrelated HCC. Here we report an interim analysis of 20 patients from a larger, ongoing trial. PATIENTS AND METHODS Study Design. During the study period, a total of 23 patients fulfilled all the criteria and conditions for the study, and 3 patients denied participating in the clinical trial. A total of 20 patients with HCC and chronic liver disease caused by HCV were recruited into this study. Before entering the trial, all the patients had received potentially curative treatments with surgical resection or percutaneous ethanol injection therapy. Serum HCV RNA (Amplicor, Nippon Roche Co., Tokyo, Japan) was examined at the time of study entry and 6 months after that. All the patients had anti-hcv antibody and HCV RNA in the serum, and no patient had concomitant infection with hepatitis B virus. Patients with evidence of decompensated liver disease (ascites, hemorrhage from esophageal varices, serum bilirubin 3 mg/dl, or hepatic encephalopathy) or severe biochemical 228

2 HEPATOLOGY Vol. 32, No. 2, 2000 IKEDA ET AL. 229 findings (albumin 2.5 g/dl, or platelet count 50,000/mm 3 ) were excluded from the study. Patients were randomly allocated into 2 groups: group A received natural IFN- (Toray Co., Tokyo, Japan) in a dose of 6 million units twice a week for 36 months; group B received no therapy. Placebo injections were not given in the latter group. Treated and untreated patients were followed at intervals of 1 month for a median observation period of 25.0 months. The endpoint of the study was tumor recurrence after treatment. All patients gave written informed consent. The Ethical Committee of Toranomon Hospital approved the purpose as well as the entire content of the study. Patient Characteristics. Among the 20 eligible patients, 10 patients were randomized to have IFN therapy (group A) and the other 10 patients to receive no therapy (group B). There were 13 men and 7 women, 51 to 70 years old, with a median age of 61 years. The diagnosis of HCC was established in resected liver specimens in 16 patients, fine needle biopsy in 2, and typical hypervascular characteristic on angiography in 2. Surgically resected specimens and needle biopsy also assessed the associating liver disease: 3 patients had chronic hepatitis and 14 had cirrhosis at the time of study entry, and the remaining 3 patients had already been diagnosed as having pathologically proven cirrhosis 1 to 3 years before the initiation of the study. The median age in group A was slightly lower than that of the group B (60 vs years, P.65). Male to female ratios were 8:2 in group A, and 7:3 in group B. Table 1 outlines the demographic and clinical characteristics of the 2 treatment groups. There were no significant differences between the 2 groups in regard to gender or liver function tests. Follow-up and Diagnosis of HCC. Physicians observed the patients every 4 weeks after entering the study. Data from liver function tests and hematologic and virologic examinations were measured every month. To find any recurred HCC nodules at an early stage, imaging diagnosis was performed every 3 months by using ultrasonography and computerized tomography. Alpha-fetoprotein and des-gammacarboxyprothrombin were also assayed every 2 months. When angiography showed a characteristic hypervascular nodule, it was usually a specific finding for HCC in these follow-up patients, and histologic confirmation was usually not required in the majority of these HCC patients. Most of the angiographically diagnosed HCC patients showed intrahepatic multiplicity and pathognomonic findings of capsule formation or nodule-in-nodule appearance or even portal vein invasion. If angiographic study did not show any hypervascular stain in a small hepatic nodule, a histologic study was always performed. No patients were lost to follow-up, and none died until the end of the observation period. The date of the last follow-up for this study was January 20, The patients have been followed for a median observation period of 25.0 months after randomization, and subsequent follow-up has ranged from 2.0 months to 34.6 months. Statistical Methods. Obtained clinical data was analyzed on an intention-to-treat basis. Standard statistical measures and procedures were used in calculations. The 2, Fisher s exact test, and Mann- Whitney U tests were used to analyze the differences of background features and biochemical data between the 2 groups. HCC appearance rate was calculated from a period between the randomization and recurrence of HCC in both groups, using the Kaplan-Meier technique. 20 The differences in recurrence curves were tested using the log-rank test. A P value of less than.05 with 2-tailed analysis was considered to be significant. Data analysis was performed using the computer program SAS version 6.11 (SAS Institute Inc., Cary, NC). 21 RESULTS Side Effects and Toxicity of Interferon. In group A, side effects of the IFN included the expected symptoms of fever, chills, myalgias, and headaches after the first few injections of IFN TABLE 1. Profiles and Laboratory Tests of the Patients Characteristic Group A (IFN) Groups Group B (Placebo) Patient characteristics No. of patients Median age (yr) (range) 60 (54-70) 64.5 (51-69).65 Sex (male/female) 7/3 6/4.64 Positive HBs antigen 0 0 NS Positive HCV antibody 10 (100%) 10 (100%) NS Positive HCV RNA 10 (100%) 10 (100%) NS Chronic hepatitis/cirrhosis 2/8 1/9.53 Decompensated cirrhosis 0 0 NS Cancer characteristics before treatment Number of nodules Solitary 9 9 NS Multiple 1 1 Size of maximal tumor (median, range) 22 (12-45) 20 (14-30).73 Vascular invasion 0 0 NS Capsule formation 4/8 3/8 NS Histologic differentiation Well 1/8 1/8 NS Moderate 7/8 7/8 Cancer therapy Surgical resection 8 (80%) 8 (80%) NS Ethanol injection 2 (20%) 2 (20%) Laboratory findings, median (range) Albumin (g/dl) 3.4 ( ) 3.25 ( ).66 Bilirubin (mg/dl) 0.7 ( ) 0.8 ( ).36 AST (IU) 39 (23-81) 55 (21-104).24 ALT (IU) 29 (15-101) 42 (7-66).50 -GTP (IU) 59 (17-314) 58 (24-113).68 Red blood cell (million/ cmm) 4.01 ( ) 4.04 ( ).86 White blood cell ( 1,000/ cmm) 3.4 ( ) 3.5 ( ).76 Platelet ( 1,000/cmm) 119 (50-292) 109 (51-415).70 Abbreviations: HBs, hepatitis B surface; NS, not significant; -GTP, gamma glutamyl transpeptidase. * Nonparametric test ( 2 test, Fisher s exact test, or Mann-Whitney U test). Histologic findings for surgically resected specimen. followed by fatigue, anorexia, weight loss, irritability, concentration difficulty, sleep disturbance, and emotional lability. Although decreases in platelet and leukocyte counts were also found in all the patients in group A, a severe degree of thrombocytopenia and leukocytopenia, requiring a reduction of IFN dosage, was not found during the treatment. In both groups, none of the patients developed decompensated liver disease with ascites, encephalopathy, jaundice, or variceal bleeding. IFN therapy was discontinued in 1 patient in the treated group, because of a slight degree of retinal hemorrhage 19 months after the initiation of IFN therapy. His retinopathy was resolved after several weeks with discontinuation of the therapy. He, nonetheless, was treated for 19 months and has been regarded as a treated patient on an intention-to-treat basis. Virological and Biochemical Changes During the Observation. None of the 20 patients lost HCV-RNA during the entire observation period in the study. The median serum aspartate transaminase (AST) and alanine transaminase (ALT) activity at entry were 39 IU/L and 29 P*

3 230 IKEDA ET AL. HEPATOLOGY August 2000 IU/L in group A (IFN therapy group), and 55 IU/L and 42 IU/L in group B (untreated group), respectively. Median AST values in groups A and B were 57 IU/L and 57 IU/L at the end of the third month, 59.5 IU/L and 61 IU/L at the sixth month, and 44 IU/L and 76 IU/L at the 12th month, respectively. Median ALT values in groups A and B were 62 IU/L and 55 IU/L at the end of the third month, 77.5 IU/L and 53.5 IU/L at the sixth month, and 42 IU/L and 68 IU/L at the 12th month, respectively. Although no significant differences were found in transaminase values between the 2 groups at the third and sixth months, transaminases tended to decrease at the 12th month in group A. Recurrence Rates of HCC. During the observation period of 2.8 years, HCC recurred in 8 patients: 1 patient belonged to group A and the remaining 7 patients to group B (Fig. 1). The number of the patients with tumor recurrence in group B was significantly higher than that of group A ( 2 test with Yates correction: P.022; Fisher s exact test: P.020). The cumulative recurrence rate of all patients was 33.3% at the end of the first year and 49.9% at the end of the second year, respectively. The recurrence rates in groups A and B were 0% and 62.5% at the end of the first year, and 0% and 100% at the end of the second year, respectively. The recurrence rate in group A was significantly lower than that of group B (log-rank test: P.0004). Relationship Between Background Features and Incidence of HCC Recurrence. HCC recurrence was found in 4 (44.4%) of 9 patients of 60 years or younger during the observation period, and in 4 (36.4%) of 11 patients of more than 60 years ( 2 test with Yates correction: P.71). Five men (38.5%) and 3 women (42.9%) showed tumor recurrence at the end of the follow-up period (see Table 2). Recurrence was found in 5 (50.0%) of 10 patients with a tumor size of 20 mm or less, and in 3 (30.0%) of 10 patients with a larger tumor of 21 mm or more (P.65). Tumor multiplicity, capsule formation, and histologic differentiation also did not affect the recurrence rate. The influences of initial biochemical data were also analyzed on the incidence of HCC recurrence. Three (33.3%) of 9 patients with an albumin concentration of 3.5 g/dl or more developed HCC recurrence, and 5 (45.5%) of 11 patients with an albumin of less than 3.5 g/dl showed a recurrence (P.93). Recurrence was found in 4 (50.0%) of 8 patients with a FIG. 1. Cumulative recurrence rate of HCC in patients with and without interferon therapy. TABLE 2. Characteristics of 8 Recurrent Tumors in Groups A and B Characteristics platelet concentration of less than 100,000/ L and 4 (33.3%) of 12 patients with a high concentration (P.78). The incidence of recurrence was slightly higher in patients with AST values of 50 IU/L or higher (5 of 9, 55.5%) than in patients with lower AST concentration (3 of 11, 27.3%) (P.41). Among various background characteristics and laboratory data, only the IFN treatment factor influenced the recurrence rate after curative therapy (P.022 by the 2 test with Yates correction, P.020 by Fisher s exact test; Table 3). DISCUSSION Group A (IFN) Group B (Placebo) Features in diagnostic procedures Detection by computed tomography 1 7/7 Detection by angiography 1 6/7 Alpha-fetoprotein (ng/ml), median (range) (3-1150) DCP# (IU/L), median (range) ( ) Characteristics of tumor Size (mm), median (range) 8 14 (12-60) Tumor multiplicity 0/1 (0%) 5 (71.4%) Capsule formation 1/1 (100%) 2/7 (28.6%) Vascular invasion 0/1 0/7 Histologic differentiation* Well 0/1 1/1 Moderate 1/1 0/1 Number of Recurrence 1 7 Abbreviation: DCP, Des-gamma-carboxyprothrombin. * Histologic classification for surgically resected specimen. Because the life expectancy of patients with HCV-related chronic liver disease is largely influenced by development and recurrence of HCC in the clinical course, and because an effective and truly curative therapy for HCC still remains limited at best, tertiary prevention of HCC is of great importance after removal of primary tumor nodules. Recognition of the Factors TABLE 3. Factors Affecting the Recurrence of HCC After Curative Treatment Category Number of Recurrences P* Age (yr) 60 (n 9) 4 (44.4%) (n 11) 4 (36.4%) Gender Male (n 13) 5 (38.5%).85 Female (n 7) 3 (42.9%) Tumor diameter 20 mm (n 10) 5 (50.0%) mm (n 10) 3 (30.0%) Albumin 3.5 g/dl (n 11) 5 (45.5%) g/dl (n 9) 3 (33.3%) Bilirubin 1.1 mg/dl (n 15) 7 (46.7%) mg/dl (n 5) 1 (20.0%) Platelet count 100,000/cmm (n 8) 4 (50.0%) ,000/cmm (n 12) 4 (33.3%) AST 50 IU/L (n 11) 3 (27.3%) IU/L (n 9) 5 (55.5%) ALT 50 IU/L (n 12) 4 (33.3%) IU/L (n 8) 4 (50.0%) IFN Yes (n 10) 1 (10.0%).022 No (n 10) 7 (70.0%) * 2 test (with Yates correction).

4 HEPATOLOGY Vol. 32, No. 2, 2000 IKEDA ET AL. 231 conditions associated with HCC recurrence in actual clinical observation can contribute to the prevention of recurrence, ensuring more effective management of patients with HCVrelated HCC. Therefore, this trial was undertaken to evaluate whether a long-term IFN therapy could decrease the recurrence rate of HCC after curative therapy. There was no significant difference in the background features and laboratory tests at study entry between the 2 groups, suggesting a proper randomization had been performed. None of the patients with or without IFN therapy cleared serum HCV RNA during the observation period, and serum transaminase values did not show any differences between the 2 groups. Of 20 patients who entered the randomized controlled trial, only 1 (10.0%) of 10 with IFN therapy developed HCC recurrence after the randomization compared with 7 (70.0%) of 10 untreated controls during the follow-up period ( 2 test with Yates correction P.022). The cumulative recurrence rate in the treated group was also significantly lower than that of the untreated group (log-rank test, P.0004). Although the sample size of the study is small and the trial is still in progress, the results strongly indicate that IFN suppresses the recurrence rate after potentially curative treatment of HCC. Biochemical and virologic improvement was not associated with the recurrence rate, whereas several investigators have related the primary carcinogenesis rate to transaminase fluctuation in HCV-related hepatitis. 17,22 The reason why IFN administration suppresses the carcinogenesis rate in HCV-related cirrhosis remains uncertain. One reason may be that IFN acts as an antitumor agent in the early stage of HCC. Another explanation for the decreased carcinogenesis is the antiviral effect of IFN. Human lymphoblastoid IFN- has been shown to have a powerful antiproliferative effect on the human hepatoma cell line PLC/PRF/5 in a dose-dependent manner, both in vitro and in vivo, after implantation in nude mice. 18 Lai et al. 19 showed that IFN induced objective tumor regression in a significant number of patients with inoperable HCC in a randomized controlled trial. Considering the period between randomization and HCC recurrence in our study, IFN may have a direct antitumor effect on clinically undetectable HCC. There have been several studies showing primary anticarcinogenic activity of IFN in patients with HCV-related chronic liver diseases. Moreno et al. 23 reported that IFN induced remission of liver fibrosis. Control of necroinflammatory processes may, therefore, induce a suppression of the growth process of HCC. Tarao et al. 24 reported that high transaminase activity resulted in an increased HCC recurrence rate. A randomized controlled trial of IFN for patients with cirrhosis showed that IFN therapy decreased the HCC appearance rate in association with disappearance of HCV RNA. 16 We also showed that IFN suppressed the hepatocellular carcinogenesis rate in patients with chronic hepatitis type C, especially in those with a decrease in transaminase level after therapy. 17 Taking into account that hepatocellular carcinogenesis in HCV-related chronic liver disease is accelerated by a prolonged period of necroinflammation of hepatocytes, IFN is hypothesized to diminish the HCC appearance rate through suppression of HCV replication. Because the entire process of hepatocellular carcinogenesis from initial transformation of a hepatocyte to detectable growth is considered to take at least a several years, the influence of IFN on the carcinogenesis rate or recurrence rate might not be evaluated in as short a period as a few years. Indeed as the rapidity of tumor growth may depend on individual tumor characteristics, many efforts should be made to understand ordinary carcinogenesis and the recurrence process in chronic liver disease from epidemiologic and detailed clinicopathologic analysis such as this study. Aside from the exact mechanism of the prevention of HCC recurrence, our study showed an encouraging result in the medical management of HCC. Because only 20 patients were included in this study, a long-term follow-up study with an increased number of cases is now under way to confirm the activity and the mode of IFN action. REFERENCES 1. Bruix J, Calvet X, Costa J, Ventura M, Bruguera M, Castillo R, Barrera JM, et al. Prevalence of antibodies to hepatitis C virus in Spanish patients with hepatocellular carcinoma and hepatic cirrhosis. Lancet 1989;2: Colombo M, Kuo G, Choo QL, Donato MF, Del Ninno E, Tommasini MA, Dioguardi N, et al. Prevalence of antibodies to hepatitis C virus in Italian patients with hepatocellular carcinoma. Lancet 1989;2: Hasan F, Jeffers LJ, Medina MD, Reddy KR, Parker T, Schiff ER, Houghton M, et al. Hepatitis C associated hepatocellular carcinoma. HEPATOL- OGY 1990;12: Kew MC, Houghton M, Choo QL, Kuo G. Hepatitis C virus antibodies in southern African blacks with hepatocellular carcinoma. Lancet 1990; 335: Ikeda K, Saitoh S, Koida I, Arase Y, Tsubota A, Chayama K, Kumada H, Kawanishi M. A multivariate analysis of risk factors for hepatocellular carcinogenesis A prospective observation of 795 cases with viral and alcoholic cirrhosis. HEPATOLOGY 1993;18: Tsukuma H, Hiyama T, Tanaka S, Nakao M, Yabuuchi T, Kitamura T, Nakanishi K, et al. Risk factors for hepatocellular carcinoma among patients with chronic liver disease. N Engl J Med 1993;328: Ikeda K, Saitoh S, Suzuki Y, Kobayashi M, Tsubota A, Koida I, Arase Y, et al. Disease progression and hepatocellular carcinogenesis in patients with chronic viral hepatitis A prospective observation of 2215 patients. J Hepatol 1998;28: Franco D, Smadja C, Meakins JL, Berthoux L, Grange D. Improved early results of elective hepatic resection for liver tumors: one hundred consecutive hepatectomies in cirrhotic and noncirrhotic patients. Arch Surg 1989;124: Nagao T, Inoue S, Yoshimi F, Sodeyama M, Omori Y, Mizuta T, Kawano N, et al. Postoperative recurrence of hepatocellular carcinoma. Ann Surg 1990;211: Yamanaka N, Okamoto,E, Toyosaka A, Mitunobu M, Fujiwara S, Kato T, Fujimoto J, et al. Prognostic factors after hepatectomy for hepatocellular carcinomas: a univariate and multivariate analysis. Cancer 1990;65: Arii S, Tanaka J, Yamazoe Y, Minematsu S, Morino T, Fujita K, Maetani S, et al. Predictive factors for intrahepatic recurrence of hepatocellular carcinoma after partial hepatectomy. Cancer 1992;69: Ikeda K, Saitoh S, Tsubota A, Arase Y, Chayama K, Kumada H, Watanabe G, et al. Risk factors for tumor recurrence and prognosis after curative resection of hepatocellular carcinoma. Cancer 1993;71: Davis GL, Balart LA, Schiff ER, Lindsay K, Bodenheimer HC, Perrillo RP, Carey W, et al. Treatment of chronic hepatitis C with recombinant interferon alfa. A multicenter, randomized, controlled trial. N Engl J Med 1989;321: Di Bisceglie AM, Martin P, Kassianides C, Lisker-Melman M, Murray L, Waggoner J, Goodman Z, et al. Recombinant interferon alfa therapy for chronic hepatitis C: a randomized, double-blind, placebo-controlled trial. N Engl J Med 1989;321: Causse X, Godinot H, Chevallier M, Chossegros P, Zoulim F, Ouzan D, Heyraud JP, et al. Comparison of 1 or 3 MU of interferon alfa-2b and placebo in patients with chronic non-a, non-b hepatitis. Gastroenterology 1991;101:

5 232 IKEDA ET AL. HEPATOLOGY August Nishiguchi S, Kuroki T, Nakatani S, Morimoto H, Takeda T, Nakajima S, Shiomi S, et al. Randomized trial of effects of interferon-alpha on incidence of hepatocellular carcinoma in chronic active hepatitis C with cirrhosis. Lancet 1995;346: Ikeda K, Saitoh S, Arase Y, Chayama K, Suzuki Y, Kobayashi M, Teubota A, et al. Effect of interferon therapy on hepatocellular carcinogenesis in patients with chronic hepatitis type C a long-term observation study of 1643 patients using statistical bias correction with proportional hazard analysis. HEPATOLOGY 1999;29: Dunk AA, Ikeda T, Pignatelli M, Thomas HC. Human lymphoblastoid interferon: in vitro and in vivo studies in hepatocellular carcinoma. J Hepatol 1986;2: Lai CL, Lau JY, Wu PC, Ngan H, Chung HT, Mitchell SJ, Corbett TJ, et al. Recombinant interferon-alpha in inoperable hepatocellular carcinoma: a randomized controlled trial. HEPATOLOGY 1993;17: Kaplan EL, Meier P. Nonparametric estimation for incomplete observation. J Am Stat Assoc 1958;53: SAS Institute Inc.: SAS/STAT User s Guide, Release 6.11 Edition. Cary, NC, USA, Kasahara A, Hayashi N, Mochizuki K, Takayanagi M, Yoshioka K, Kakumu S, Iijima A, et al. Risk factors for hepatocellular carcinoma and its incidence after interferon treatment in patients with chronic hepatitis C. Osaka Liver Disease Study Group. HEPATOLOGY 1998;27: Moreno MG, Muriel P. Remission of liver fibrosis by interferon-alpha 2b. Biochem Pharmacol 1995;50: Tarao K, Takemiya S, Tamai S, Sugimasa Y, Ohkawa S, Akaike M, Tanabe H, et al. Relationship between the recurrence of hepatocellular carcinoma (HCC) and serum alanine aminotransferase levels in hepatectomized patients with hepatitis C virus-associated cirrhosis and HCC. Cancer 1997;79: