Clinical and molecular insights into the hepatocellular carcinoma tumour marker des‐γ‐carboxyprothrombin

Des‐γ‐carboxyprothrombin (DCP) is known as a tumour marker for hepatocellular carcinoma (HCC). Various tumour markers have been developed for serological diagnosis of cancers, including HCC, in order to increase the survival rate of cancer patients. The currently recommended combined testing of DCP and α‐fetoprotein (AFP) or Lens culinaris agglutinin‐reactive fraction of α‐fetoprotein has been established to diagnose HCC. This combined testing using several tumour markers helps to increase the sensitivity of diagnosis of HCC, thus significantly increasing the clinical usefulness of DCP. The excessive production of DCP may be related to worse tumour behaviour, such as the presence of vascular invasion and intrahepatic metastasis of HCC cells. A high level of DCP was suggested to be useful as one of the factors in new recipient selection criteria of liver transplantation. The clinical use of DCP, therefore, might play a vital role in predicting tumour behaviour in patients with HCC. That said, the basic mechanism of DCP production has not been fully clarified. Various factors such as vitamin K₂ and γ‐glutamyl carboxylase may contribute to the production of DCP and have a complex relationship. Moreover, recent studies have revealed that DCP functions as a growth factor and might play significant roles in cancer progression. Thus, DCP represents a potential target of drug discovery to establish new chemotherapeutic strategy for HCC. However, various issues have to be resolved to construct a novel therapy for HCC‐targeting DCP. Innovation is required to make further progress in examining DCP.     

Clinical significance of half‐lives of tumor markers α‐fetoprotein and des‐γ‐carboxy prothrombin after hepatectomy for hepatocellular carcinoma

Aim

The prognostic significance of the half‐lives (HLs) of α‐fetoprotein (AFP) and des‐γ‐carboxy prothrombin (DCP) in patients undergoing hepatectomy for hepatocellular carcinoma (HCC) is unclear. We evaluated the HLs of AFP and DCP in a cohort of such patients.

Methods

This study included data on 202 patients with HCC who underwent curative hepatectomy and had preoperative AFP concentrations ≥100 ng/mL or DCP ≥200 mAU/mL. We calculated the HLs of AFP and DCP from their values just before and 1 month after hepatectomy. We identified three groups: a normalization group, tumor marker concentrations within normal range 1 month post‐hepatectomy; a long group, HL of AFP ≥7 days or DCP ≥4 days; and a short group, remaining patients. We evaluated associations between HL and prognosis.

Results

Three‐year recurrence‐free survival (RFS) in the normalization (n = 70), short (n = 71), and long groups (n = 61) was 41.3%, 46.0%, and 16.8%, respectively (P = 0.002). Five‐year overall survival (OS) of normalization, short, and long groups was 72.6, 70.6 and 43.8%, respectively (P = 0.002). Multivariate analysis revealed that long HL is an independent risk factor for poor RFS (hazard ratio [HR] 2.21, P = 0.0006) and poor OS (HR 2.70, P = 0.004). The extrahepatic recurrence rate was 21.3% (13/61) in the long group, which is higher than in the normalization group (8.6%, 6/70) (P = 0.04) and short group (9.9%, 7/71) (P = 0.07).

Conclusion

Post‐hepatectomy HLs of AFP and DCP are predictors of long‐term outcome in patients with HCC.     

Predicting the treatment effect of sorafenib using serum angiogenesis markers in patients with hepatocellular carcinoma

Background and Aim: Sorafenib, the first agent demonstrated to have efficacy to improve the survival of patients with advanced hepatocellular carcinoma (HCC), is an active multikinase inhibitor affecting angiogenesis and tumor proliferation. We analyzed cytokines related to angiogenesis or cell proliferation, and tried to determine their utility as biomarkers of sorafenib treatment effect for HCC. Methods: Nine serum cytokines (angiopoietin‐2 [Ang‐2], follistatin, granulocyte colony‐stimulating factor [G‐CSF], hepatocyte growth factor [HGF], interleukin‐8 [IL‐8], leptin, platelet‐derived growth factor‐BB, platelet endothelial cell adhesion molecule‐1, and vascular endothelial growth factor) were measured in 30 HCC patients treated with sorafenib, and the effects of treatment were compared using modified Response Evaluation Criteria in Solid Tumors. Results: All but IL‐8 were significantly higher at baseline in patients with progressive disease. Progression‐free survival was significantly shorter in patients with high levels of Ang‐2, G‐CSF, HGF, and leptin, and the hazard ratios were 2.51, 6.89, 2.55, and 4.14, respectively. As the number of cytokines at a high level increased, the treatment response deteriorated. Disease progression was seen in three of 12 (25.0%) patients with zero to two high biomarkers, two of six (33.3%) patients with 3–5 high biomarkers, and 10 of 12 (83.3%) patients with six to eight high biomarkers (P = 0.008). The prognosis of all patients with eight high biomarkers was progressive disease. Conclusion: High levels of serum cytokines at baseline were correlated with poor effects of sorafenib treatment in patients with HCC.     

Favorable α‐fetoprotein decrease as a prognostic surrogate in patients with hepatocellular carcinoma after radiofrequency ablation

Background and Aim: To assess the significance of adequate α‐fetoprotein decrease in monitoring the treatment effects of radiofrequency ablation (RFA) in hepatocellular carcinoma (HCC) patients. Methods: A total of 72 RFA treatments in 54 HCC patients were analyzed. The favorable α‐fetoprotein decrease was defined as the α‐fetoprotein half‐life of less than 7 days. The efficacy of the ablation response is assessed by standard imaging modality, a computed tomography scan 1 month after RFA. We assessed the correlation between different α‐fetoprotein decreases and treatment outcomes by standard imaging modality. Results: Of the 72 therapies, 15 (21%) were favorable α‐fetoprotein decreases. Fifty‐one (71%) therapies showed concordant results through standard image modality and α‐fetoprotein decrease, including 14 (27%) therapies with a complete radiological response and favorable α‐fetoprotein decrease, and the remaining 37 (73%) therapies with an incomplete radiological response and unfavorable α‐fetoprotein decrease. The accuracy was 70.8% by using α‐fetoprotein decrease in the detection treatment response based on a complete radiological response. Among the 34 therapies with a complete radiological response, 14 therapies with a favorable α‐fetoprotein decrease had a better disease‐free survival curve than 20 therapies with an unfavorable α‐fetoprotein decrease (P = 0.003). Only one case had a favorable α‐fetoprotein decrease, but incomplete radiological response, with massive necrosis, with the exception of a small residual tumor. Conclusions: A favorable α‐fetoprotein decrease has better predictive power for disease‐free survival than for an unfavorable α‐fetoprotein decrease. HCC patients after RFA with an unfavorable α‐fetoprotein decrease should be considered to have undergone incomplete treatment, despite the complete response by standard image modality post‐RFA.     

Postoperative surveillance with monthly serum tumor markers after living‐donor liver transplantation for hepatocellular carcinoma

Aim: Recurrence of hepatocellular carcinoma (HCC) after liver transplantation decreases patient survival. The usefulness of post‐transplant surveillance with tumor markers, however, is not clear. We evaluated our cumulative experience with recurrent HCC detected during post‐transplant surveillance. Methods: We analyzed 100 patients with HCC detected in the explanted liver. Monthly to bimonthly measurement of tumor markers and yearly computed tomography were scheduled postoperatively. Results: Preoperatively, 82 met the Milan criteria. The histological findings indicated that 61 fulfilled the Milan criteria. In nine patients, HCC recurred 10 months (2–29) after liver transplantation in the graft (n = 1), lung (n = 2), bone (n = 3) and multiple organs (n = 3). In all nine recipients, HCC was first suspected based on an increase in tumor marker levels. Recurrent HCC was confirmed by computed tomography (n = 7) or magnetic resonance imaging (n = 2) within 4 months (0–6) after first identifying an increase in the tumor marker levels. Six cases were treated surgically, two of which achieved prolonged survival of 16 and 38 months. Conclusion: Frequent measurement of α‐fetoprotein and des‐γ carboxy prothrombin was useful for detecting recurrent HCC and may be useful long‐term follow‐up markers for post‐transplant surveillance.     

Prognostic value of 18F‐FDG PET for hepatocellular carcinoma patients treated with sorafenib

Background: Sorafenib (Nexavar) is an orally active multikinase inhibitor that is approved for the treatment of hepatocellular carcinoma (HCC). In this study, we used ¹⁸F‐2‐fluoro‐2‐deoxyglucose (¹⁸F‐FDG) with positron emission tomography (PET) to predict the treatment outcome of sorafenib in patients with advanced HCC. Materials and methods: A total of 29 patients with HCC were included. Baseline ¹⁸F‐FDG PET scans were performed a median of 14 days before sorafenib treatment. Sorafenib was administered orally at a dose of 400 mg twice daily. For statistical analysis, the standardized uptake value (SUV) of the most hypermetabolic lesion was obtained and assigned as the SUVmax for each patient. Results: Among 29 patients, one patient achieved partial remission and 14 patients showed stable disease. The overall survival (OS) and progression free survival (PFS) were 5.1 months [95% confidence interval (CI): 0.0–12.0] and 3.8 months (95% CI: 1.4–6.2). The multivariate analysis of OS showed that four indices, Eastern Cooperative Oncology Group performance status, α‐fetoprotein (AFP) concentration, portal vein thrombosis and SUVmax were significant prognostic factors (P=0.030, P=0.024, P=0.020 and P=0.015 respectively). AFP concentration and SUVmax were independent prognostic factors for PFS, too (P=0.003 and P=0.026 respectively). When the patients were divided into two groups: low SUVmax (n=10; <5.00) and high SUVmax (n=19;≥5.00), the low SUV group showed significantly longer OS and PFS (P=0.023 and P=0.042 respectively). Conclusion: Our study showed that the degree of FDG uptake is an independent prognostic factor in patients with HCC who undergo sorafenib treatment.     

Differential vascular endothelial growth factor A protein expression between small hepatocellular carcinoma and cirrhosis correlates with serum vascular endothelial growth factor A and α‐fetoprotein

Background/Aims: Drugs with antivascular endothelial growth factor A (anti‐VEGF‐A) action are under clinical evaluation with encouraging results in advanced hepatocellular carcinoma (HCC). The relative VEGF‐A protein expression in non‐advanced HCC and in the cirrhotic non‐tumoral tissue in the same patient, a variable that could be important for treatment efficacy, has been investigated with conflicting results, only using the cirrhotic tissue surrounding the neoplasm (CS). Methods: We measured, for the first time, VEGF‐A expression in non‐advanced HCC and in the respective CS and cirrhotic tissue at a distance from the tumour (CD), in 24 patients who underwent liver transplantation. Results: VEGF‐A protein was more expressed (P<0.05) in HCC than in CD, while no difference was found between HCC and CS. In HCC patients with a serum α‐fetoprotein (AFP) higher than 20 ng/ml, VEGF‐A protein expression in HCC was higher than in the corresponding CD in 83% of cases and AFP and serum VEGF‐A corrected for the platelet count positively correlated with the differential VEGF‐A protein expression between HCC and CD. Conclusion: Our data provide a rationale for clinical trials involving anti‐VEGF‐A treatments in patients with non‐advanced HCC, and suggest that serum AFP and VEGF‐A are variables to be taken into account in these studies.     

Recent topics on α‐fetoprotein

Zinc‐fingers and homeoboxes 2 (ZHX2) and zinc‐finger and BTB domain containing 20 (ZBTB20) repress the postnatal expression of α‐fetoprotein (AFP) by interacting with the AFP gene promoter regions. ZHX2 inhibits the expression of AFP and cyclins A and E. ZBTB20 is negatively regulated by CUX1, which promotes cell‐cycle progression, suggesting that AFP reactivation is closely linked to hepatocyte proliferation. A slight elevation in the serum AFP level often occurs in patients with chronic hepatitis C in the absence of hepatocellular carcinoma (HCC) and is an independent risk factor for HCC development to complement the fibrosis stage. In addition, the sustained elevation of AFP after interferon therapy is a risk factor of HCC development. AFP levels are clinically useful in predicting the outcomes of liver transplantation and sorafenib therapy for HCC patients. A low preoperative AFP level is a predictor of long‐term survival and is associated with a low recurrence rate of HCC after liver transplantation. AFP response (≥20% decrease in AFP during 6–8 weeks of treatment) rather than radiological outcomes is a significant prognostic factor for survival in sorafenib‐treated HCC patients. Highly sensitive Lens culinaris agglutinin‐reactive AFP (AFP‐L3) is 5–10 times more sensitive than conventional AFP‐L3, and useful for early detection of HCC in patients with total AFP below 20 ng/mL.     

Des-gamma-carboxyprothrombin, alpha-fetoprotein and AFP-L3 in patients with chronic hepatitis, cirrhosis and hepatocellular carcinoma

Background and Aim: Hepatocellular carcinoma (HCC) is a common complication in patients with chronic viral hepatitis. Detection of HCC at an early stage is critical for a favorable clinical outcome. The study aim was to: (i) compare the levels of des‐γ‐carboxyprothrombin (DCP), α‐fetoprotein (AFP) and AFP‐L3 in HCC patients and in chronic viral hepatitis patients without HCC; (ii) define the level of each tumor marker with the best sensitivity and specificity for HCC diagnosis; and (iii) to correlate the levels of these markers with respect to size and tumor burden. Methods: Two hundred and forty patients with either hepatitis B virus (HBV) or hepatitis C virus (HCV) infection were studied. These included 144 with HCC, 47 with chronic hepatitis (fibrosis stage I–III on liver biopsy) and 49 with cirrhosis. Results: Levels of DCP, AFP and AFP L‐3 were significantly higher in patients with HCC than in those without HCC (P ≤ 0.0001). Receiver–operating curves (ROC) indicated that the cut‐off value with the best sensitivity and specificity for each test was ≥84 mAU/mL for DCP, ≥25 ng/mL for AFP and ≥10% for AFP‐L3. The sensitivity, specificity and positive predictive value (PPV) for DCP was 87%, 85% and 86.8%, for AFP 69%, 87% and 69.8%, and for AFP‐L3 56%, 90% and 56.1%, respectively. DCP levels were below the ROC cut‐off in all patients without HCC. In patients with single lesions, there was a direct correlation of DCP to tumor size. High levels of AFP correlated with diffuse type of HCC. All three markers were significantly elevated in the presence of metastatic HCC. No advantage was observed by combining two or three markers for HCC diagnosis. Conclusion: DCP had the highest sensitivity and PPV for HCC diagnosis, had a direct correlation with tumor size, and was not elevated in any patients without HCC. DCP should be used as the main serum test for HCC detection.     

Clinical course of sorafenib treatment in patients with hepatocellular carcinoma

Abstract

Objective. Sorafenib has been shown to improve survival of patients with advanced hepatocellular carcinoma (HCC). However, its tolerance in clinical practice has not been well evaluated, and whether sorafenib should be continued in cases of tumor progression or intolerance has not been established. The authors retrospectively assessed sorafenib tolerability, and evaluated the clinical course in patients who showed progression during sorafenib treatment. Material and methods. Between March 2008 and July 2010, 80 patients with advanced HCC were treated with sorafenib. Results. With a median of 78.5 days of treatment, 15% discontinued sorafenib due to adverse events. The duration was significantly longer in patients with Child–Pugh class A liver function (233 ± 240 days) than in those with Child–Pugh class B (100 ± 136 days; p = 0.006). The overall progression rate was 53% (43/80), with a median time to progression of 105 days (95% confidence interval, 59–150 days). After progression, 14 patients received conservative care only (group 1), 14 continued sorafenib monotherapy (group 2), 6 changed to treatment without sorafenib (group 3) and 9 underwent additional treatment with concomitant sorafenib (group 4). Survival after progression was significantly better in groups 2, 3 and 4 than in group 1 (p = 0.001). Conclusions. Sorafenib was tolerable for most patients in clinical practice and may be continued in patients who show progression during sorafenib therapy. However, it was less well tolerated in patients with Child–Pugh class B liver function and should be used with caution in these patients.     

Des-gamma-carboxyprothrombin in patients with hepatocellular carcinoma and liver cirrhosis

OBJECTIVES: To ascertain serum and tissue expression of des‐gamma‐carboxyprothrombin (DCP) in patients with hepatocellular carcinoma (HCC) and liver cirrhosis and clarify the relationship between DCP expression and prognosis. METHODS: Expression of DCP in tissues was evaluated with immunohistochemical staining using anti‐DCP antibody in 74 patients with a single primary HCC nodule and liver cirrhosis. Their serum DCP levels were determined using an enzyme immunoassay with a double antibody sandwich system. RESULTS: Positive DCP expression in cancerous and non‐cancerous tissues was related to a worse prognosis for patients with HCC and liver cirrhosis. The combined evaluation of tissue DCP expression and serum DCP level showed that prognosis was the worst for patients with positive tissue DCP expression and a high serum DCP level. Univariate analysis indicated that a lower 5‐year survival rate was significantly correlated with positive tissue DCP expression, a high serum DCP level and the combined factor of positive tissue DCP expression and a high serum DCP level. Multivariate analysis indicated that the combined factor of positive tissue DCP expression and a high serum DCP level was a significant prognostic factor. CONCLUSION: The combined evaluation of tissue DCP expression and serum DCP level is more useful than either factor alone in predicting prognosis for patients with HCC and liver cirrhosis.     

Early α‐fetoprotein response as a predictor for clinical outcome after localized concurrent chemoradiotherapy for advanced hepatocellular carcinoma

Backgrounds: There are limitations in using only radiological criteria to evaluate treatment outcomes in hepatocellular carcinoma (HCC). α‐fetoprotein (AFP) is regarded as an indicator of tumour activity in HCC. Aims: We present a novel correlation between AFP response and survival outcome in patients treated with localized concurrent chemoradiotherapy (CCRT). Materials: From 2005 to 2008, 187 locally advanced HCC patients underwent localized CCRT (external beam radiotherapy at 45 Gy over 5 weeks plus a concurrent hepatic arterial infusion of 5‐fluorouracil during the first/fifth week), followed by repetitive hepatic arterial infusional chemotherapy (HAIC) with 5‐fluorouracil and cisplatin. Among them, 149 with an elevated baseline AFP level (>20 ng/ml) were finally studied. AFP response was defined as >50% decrease from baseline, 1 month after the completion of localized CCRT. Results: Patients' characteristics were as follows: median age (52 years); Child–Pugh class A/B (n=137/12 respectively); and portal vein thrombosis (n=118). AFP responders (101 patients) had better objective responses than AFP non‐responders (48 patients) after CCRT (44.5 vs. 12.5%; P<0.001) and subsequent HAIC (51.5 vs. 16.7%; P<0.001). Both median progression‐free survival (PFS, 8.1 vs. 3.9 months; P<0.001) and overall survival (OS, 13.3 vs. 5.9 months; P<0.001) were longer in AFP responders than AFP non‐responders. In multivariate analysis, AFP response and objective response were independent factors affecting PFS and OS. Furthermore, AFP non‐responders were more likely to have extrahepatic metastasis within 6 months of treatments initiation than AFP responders (59.5 vs. 25.9%; P<0.001). Conclusions: Early AFP response may be useful not only in predicting prognosis and treatment response but also in establishing optimized treatment plans for HCC.