Preoperative FDG-PET predicts recurrence patterns in hepatocellular carcinoma

Proposal for Prognosis-Oriented Definition of Borderline Resectable Hepatocellular Carcinoma

BACKGROUND

Owing to advances in the multidisciplinary treatment of hepatocellular carcinoma (HCC), a conceptualization and definition for borderline resectable (BR) HCC, which carries a high risk of recurrence, is warranted. In this study, we aimed to define BR-HCC using a prognosis-oriented approach.

STUDY DESIGN

The study included an original cohort of 221 patients and an independent validation cohort of 181 patients who had undergone primary hepatic resection for HCC. To define biological BR-HCC, we evaluated the risk factors for early recurrence beyond the Milan criteria within 1 year after hepatic resection using multivariable logistic regression models. Subsequently, we developed high-risk scores using the identified risk factors and defined BR-HCC. The utility of high-risk score was validated in the validation cohort.

RESULTS

In the original cohort (hepatitis B virus:hepatitis C virus = 20%:29%), recurrence beyond the Milan criteria within 1 year was observed in 28 patients (13%), with a 5-year survival rate of 25%. Multivariable analysis identified risk factors for recurrence beyond the Milan criteria within 1 year, including serum alpha-fetoprotein levels of 12 ng/mL or more (p = 0.02), tumor diameters less than 5 cm (p = 0.02), tumor number 3 or more (p = 0.001), and macrovascular invasion (p = 0.04). BR-HCC was defined as a tumor with 2 or more identified risk factors, and 42 patients (19%) were diagnosed with BR-HCC, with a 5-year survival rate of 51%. In the validation cohort, 45 (25%) patients had BR-HCC, with a 5-year survival rate of 42%.

CONCLUSIONS

The prognosis-oriented definition of BR-HCC enabled us to identify patients who are susceptible to early unresectable recurrence and have poor survival after hepatic resection for HCC. For patients with BR-HCC, preoperative systemic therapy may be a viable option to improve postresection outcomes.

Quarter-Century PET/Computed Tomography Transformation of Oncology: Hepatobiliary and Pancreatic Cancer

[18F] Fluorodeoxyglucose (18F-FDG) PET/CT can improve the staging accuracy and clinical management of patients with hepatobiliary and pancreatic cancers, by detection of unsuspected metastases. 18F-FDG PET/CT metabolic parameters are valuable in predicting treatment response and survival. Metabolic response on 18F-FDG PET/CT can predict preoperative pathologic response to neoadjuvant therapy in patients with pancreatic cancer and determine prognosis. Several novel non-FDG tracers, such as 68Ga prostate-specific membrane antigen (PSMA) and 68Ga-fibroblast activation protein inhibitor (FAPI) PET/CT, show promise for imaging hepatobiliary and pancreatic cancers with potential for radioligand therapy.

Achievement of Complete Response and Drug-Free Status by Atezolizumab plus Bevacizumab Combined with or without Curative Conversion in Patients with Transarterial Chemoembolization-Unsuitable, Intermediate-Stage Hepatocellular Carcinoma: A Multicenter Proof-Of-Concept Study

Introduction

Atezolizumab plus bevacizumab therapy is extremely effective in the treatment of intermediate-stage hepatocellular carcinoma (HCC), with a response rate of 44%, as reported in the IMbrave150 trial. When tumor shrinkage is obtained, achieving complete response (CR) is possible in many cases using curative conversion with resection, ablation, or superselective transarterial chemoembolization (TACE) with curative intent. This concept, i.e., curative conversion by combining systemic therapy and locoregional therapy, has not been reported before. This multicenter proof-of-concept study was conducted to show the value of curative conversion in immunotherapy-treated intermediate-stage HCC meeting TACE-unsuitable criteria.

Methods

This study included 110 consecutive Child-Pugh A patients who received atezolizumab plus bevacizumab as first-line treatment for unresectable and TACE-unsuitable intermediate-stage HCC at seven centers in Japan. CR rate, drug-free rate, time to CR, change in liver function, efficacy in positron emission tomography (PET)-positive HCC, progression-free survival (PFS), and overall survival (OS) were assessed in patients who achieved CR using resection, ablation, superselective TACE with curative intent following atezolizumab plus bevacizumab or atezolizumab plus bevacizumab alone.

Results

Clinical or pathological CR was achieved in 38 patients (35%) (median observation period: 21.2 months). The modalities of curative conversion in 35 patients were as follows: resection, 7; ablation, 13; and superselective TACE, 15. Three patients achieved clinical CR with atezolizumab plus bevacizumab therapy alone. Among the 38 CR patients, 25 achieved drug-free status. PFS was not reached, and 3 patients experienced recurrence after reaching CR. Regarding OS, there were no deaths in any of the CR patients. The albumin-bilirubin score did not deteriorate after locoregional therapy or resection. Of seven PET-positive patients who achieved CR with atezolizumab plus bevacizumab followed by curative conversion, five achieved drug-free status.

Conclusion

The achievement of CR rate by curative conversion in patients treated with atezolizumab plus bevacizumab as the preceding therapy for unresectable and TACE-unsuitable intermediate-stage HCC was 35%. Overall, 23% of patients achieved drug-free status and no recurrence was observed from this patient subgroup with CR and drug-free status. Thus, achieving CR and/or drug-free status should be a therapeutic goal for patients with intermediate-stage HCC without vascular invasion or extrahepatic spread.

Pretreatment Metabolic Parameters Measured by 18F-FDG PET to Predict the Pathological Treatment Response of HCC Patients Treated With PD-1 Inhibitors and Lenvatinib as a Conversion Therapy in BCLC Stage C

Objectives

This study aimed to assess the pretreatment ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) as a predictor of the pathological treatment response (PTR) of hepatocellular carcinoma (HCC) patients treated with PD-1 inhibitors and lenvatinib as a conversion therapy in BCLC stage C.

Methods

All patients (n=20) underwent pretreatment ¹⁸F-FDG PET/CT and were treated with conversion therapy and surgery. Patients were categorized into responders (n=9) and non-responders (n=11) according to PTR. The parameters of PET/CT, including lesion size, SUVmean (mean standard uptake value), MTV (metabolic tumor volume), TLG (total lesion glycolysis), SUVpeak (peak standard uptake value), and TLR (tumor-to-normal liver standardized uptake value ratio), were calculated. The diagnostic efficacy was evaluated by receiver operating characteristic analysis (ROC). PTR was compared with pretreatment PET/CT parameters by using Spearman correlation analysis. The patients were followed up.

Results

There was significant difference in TLR (5.59 ± 1.90 vs. 2.84 ± 1.70, respectively; P=0.003) between responders and non-responders, with the largest area under the curve (sensitivity=100%, specificity=72.7%, AUC=0.899, 95%CI: 0.759-1.000, optimal diagnostic threshold of 3.09). The relationship between ¹⁸F-FDG PET/CT parameters and PTR indicated TLR was moderately and positively correlated with pathological treatment response, with correlation coefficients (rs) of 0.69 (P<0.01). During the follow-up, no patients died, and tumor recurrence was found in one of the responders (11.1%). In all 11 non-responders, tumor recurrence was found in six patients (54.5%) and four patients (36.4%) died.

Conclusions

TLR may be a powerful marker to predict PTR of HCC patients with BCLC stage C who were treated with conversion therapy.

The value of preoperative 18F-FDG PET metabolic and volumetric parameters in predicting microvascular invasion and postoperative recurrence of hepatocellular carcinoma

BACKGROUND

Microvascular invasion (MVI) is very important in the evaluation of hepatocellular carcinoma (HCC), but diagnosis is determined by postoperative pathology; thus, preoperative noninvasive methods will play an active role. The purpose of the study was to assess the performance of metabolic parameters of preoperative 18F-fluorodeoxyglucose PET/computerized tomography (18F-FDG PET/CT) in the prediction of MVI and postoperative recurrence in primary hepatocellular carcinoma.

METHODS

We retrospectively collected 72 patients with HCC who have performed 18F-FDG PET/CT scan before partial hepatectomy between 2016 and 2019. We used both normal liver tissue and inferior vena cava as the reference background and combined with clinicopathological features, 18F-FDG PET/CT metabolic and volumetric indices to predict MVI and postoperative recurrence of primary HCC before surgery.

RESULTS

Twenty-one of the 72 patients recurred, in recurrent cases showed higher maximum standard uptake value (SUVmax), TNR (ratio of tumor SUVmax to mean SUV [SUVmean] of the background tissue), metabolic tumor volume (MTV) and total lesion glycolysis (TLG) than nonrecurrence cases (P < 0.001). All 18F-FDG PET metabolic and volumetric indices for predicting postoperative HCC recurrence were significant on receiver-operating-characteristic (ROC) curve analyses (P < 0.05). TNRIVC, TNRNL, MTVIVC, MTVNL TLGIVC and TLGNL were significant factors for predicting MVI in HCC (P < 0.05). On multivariate analyses, MVI, SUVmax, TNRIVC, TNRNL, MTVIVC, MTVNL, TLGIVC and TLGNL (P < 0.05) are independent risk factors for predicting postoperative HCC recurrence. TNRIVC is the most relevant PET/CT parameter for predicting MVI in HCC, and MTVIVC is the most valuable for predicting postoperative HCC recurrence. Moreover, the PET/CT parameters are more accurate for prognosis with inferior vena cava as a reference background than with normal liver tissue.

CONCLUSION

18F-FDG PET/CT metabolic and volumetric indices are effective predictors, and could noninvasively provide more comprehensive predictive information on MVI and postoperative recurrence of primary HCC before surgery.

Metabolic Switch in Hepatocellular Carcinoma Patients Treated with Sorafenib: a Proof-of-Concept Trial

BACKGROUND

Sorafenib is a multikinase inhibitor used to treat advanced hepatocellular carcinoma (HCC). Recently, a preclinical trial has shown that response to sorafenib is associated with a metabolic shift towards aerobic glycolysis. To test this observation in humans, we decided to conduct a proof-of-concept trial investigating the role of metabolic shift detected on [¹⁸F]FDG PET/CT in predicting survival and tumor response in HCC patients treated with sorafenib.

METHODS

We prospectively enrolled advanced HCC patients candidate to sorafenib and undergoing [¹⁸F]FDG PET/CT at baseline, at 24 h, and at day 7 following treatment start. Response evaluation was obtained after 8 weeks according to Response Evaluation Criteria in Solid Tumors (RECIST). All clinical variables and metabolic parameters (i.e., SUVmax; metabolic tumor volume, MTV; total lesion glycolysis, TLG; and their variations, Δ) were compared with those of treatment response and correlated to progression-free (PFS) and overall survival (OS).

RESULTS

For this proof-of-concept trial, between August 2016 and August 2018, 13 patients (10 male, 3 female, median age 69) were enrolled. Considering the entire cohort, we demonstrated a significant negative correlation between ΔSUVmax at 24 h and 1 week (rho = - 0.733, p = 0.016). The metabolic shift, as expected, demonstrated median SUVmax, MTV, and TLG after 1 week lower in patients with a stable disease than a progressive disease (p = 0.019). Metabolic parameters and ECOG performance status (PS) resulted significantly correlated to PFS and OS at univariate analysis. On multivariate analysis, only median MTV at 1 week resulted as an independent prognostic factor for PFS (p = 0.033).

CONCLUSIONS

As hypothesized, [¹⁸F]FDG PET/CT resulted in able to evaluate metabolic shift at 24 h and early treatment response already 1 week after treatment start. Moreover, metabolic parameters and ECOG PS resulted in predictive and prognostic factors to PFS and OS, with MTV at 1 week appearing as an independent predictive factor for PFS.

Pretreatment Positron Emission Tomography with 18F-Fluorodeoxyglucose May Be a Useful New Predictor of Overall Prognosis Following Lenvatinib Treatment

BACKGROUND AND AIM

The aim of this study was to identify the utility of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG-PET/CT) as a predictor of overall prognosis in patients with hepatocellular carcinoma treated with lenvatinib.

METHODS

Forty-eight consecutive patients who received lenvatinib treatment were reviewed. The oncological aggressiveness of tumors estimated using 18F-FDG-PET/CT was investigated by the analysis of progression-free survival (PFS), post-progression survival (PPS), and overall survival (OS). Multivariate analysis was used to identify potential confounders for OS during lenvatinib therapy.

RESULTS

Using the Modified Response Evaluation Criteria in Solid Tumors, a tumor-to-normal liver ratio (TLR) ≥2, indicating higher oncological aggressiveness in HCCs, was associated with a better objective response to lenvatinib than a TLR <2 (78 vs. 62%), resulting in a similar PFS (p = 0.751). Because of a significantly worse PPS, OS with a TLR ≥2 was poor compared to a TLR < 2 (p = 0.012). Multivariate analysis confirmed that a TLR ≥ 2 was associated with poor OS (hazard ratio, 2.709; 95% CI, 1.140-6.436; p = 0.024). Analysis of 24 patients who received a repeat 18F-FDG-PET/CT showed that daily changes expressed as ΔTLR × 103/day over the treatment course tended to be different among the types of subsequent treatment. A R0 resection and lenvatinib-TACE sequential therapy provided good disease control (median, -4.593 and -0.024, respectively) compared with other treatments (median, 5.278) (p = 0.075).

CONCLUSION

Lenvatinib has acceptable disease control regardless of estimated tumor differentiation. A high TLR (≥2) is a poor prognostic factor of OS following lenvatinib treatment, while ΔTLR × 103/day provides useful information of disease control status.

Enhanced patterns on intraoperative contrast-enhanced ultrasonography predict outcomes after curative liver resection in patients with hepatocellular carcinoma

PURPOSE

This study aimed to clarify what hepatocellular carcinoma (HCC) phenotype, as categorized by intraoperative contrast-enhanced ultrasonography (CEUS), showed a high risk of recurrence after hepatic resection.

METHODS

Patients who underwent initial curative hepatectomy with intraoperative CEUS for a single HCC nodule were retrospectively assigned to three patterns of fine (FI), vascular (VA), and irregular (IR) according to the maximum intensity projection pattern based on intraoperative CEUS. Staining was performed for Ki-67, pyruvate kinase type M2 (PKM2), and vascular endothelial growth factor (VEGF) to assess the tumor proliferative activity, tumor glucose metabolism, and angiogenesis, respectively.

RESULTS

Of 116 patients, 18, 50, and 48 were assigned to the FI, VA and IR patterns, respectively. IR patients demonstrated a significantly worse prognosis for both the recurrence-free survival (RFS) and overall survival (OS) (P = 0.0002, 0.0262, respectively) than did patients with other patterns. A multivariate analysis revealed an IR pattern in intraoperative CEUS to be an independent predictive factor for a poor RFS, and major hepatectomy and an IR pattern were independent predictive factors for a poor OS. An IR pattern was closely related to the tumor size (≥ 3.3 cm) and poor histological differentiation and showed a high Ki-67 index, low VEGF expression, and high PKM2 expression.

CONCLUSION

IR-pattern HCCs as classified by intraoperative CEUS may be associated with a higher risk of recurrence and worse outcomes in HCC patients after hepatic resection than other patterns.

Prediction of Post-resection Prognosis Using the ADV Score for Huge Hepatocellular Carcinomas ≥13 cm

Background/Aims

Multiplication of α-fetoprotein, des-γ-carboxy prothrombin, and tumor volume (ADV score) is a surrogate marker for post-resection prognosis of hepatocellular carcinoma (HCC). This study aimed to validate the predictive power of the ADV score-based prognostic prediction model for patients with solitary huge HCC.

Methods

Of 3,018 patients, 100 patients who underwent hepatic resection for solitary HCC ≥13 cm between 2008 and 2012 were selected.

Results

The median tumor diameter and tumor volume were 15.0 cm and 886 mL, respectively. Tumor recurrence and overall survival (OS) rates were 70.7% and 66.0% at one year and 84.9% and 34.0% at five years, respectively. Microvascular invasion (MVI) was the only independent risk factor for disease-free survival (DFS) and OS. DFS and OS, stratified by ADV score with 1-log intervals, showed significant prognostic contrasts (P=0.007 and P=0.017, respectively). DFS and OS, stratified by ADV score with a cut-off of 8-log, showed significant prognostic contrasts (P=0.014 and P=0.042, respectively). The combination of MVI and ADV score with a cut-off of 8-log also showed significant prognostic contrasts in DFS (P<0.001) and OS (P=0.001) considering the number of risk factors. Prognostic contrast was enhanced after combining the MVI and ADV score.

Conclusions

The prognostic prediction model with the ADV score could reliably predict the risk of tumor recurrence and long-term patient survival outcomes in patients with solitary huge HCC ≥13 cm. The results of this study suggest that our prognostic prediction models can be used to guide surgical treatment and post-resection follow-up for patients with huge HCCs.

Efficacy and Safety of Ramucirumab in Patients with Unresectable Hepatocellular Carcinoma with Progression after Treatment with Lenvatinib

Objective A survival benefit was demonstrated for ramucirumab (RAM) in patients with unresectable hepatocellular carcinoma (uHCC) and α-fetoprotein (AFP) concentrations ≥400 ng/mL who had previously received sorafenib (SOR). However, it is unclear whether RAM has a similar efficacy in patients with uHCC that progresses after lenvatinib (LEN) treatment. This study aimed to evaluate the early anti-tumor response to RAM as a second-line treatment for advanced uHCC after LEN treatment. Methods We retrospectively assessed the efficacy and safety of RAM at 6 weeks after initiation. The therapeutic effects were evaluated according to the Response Evaluation Criteria in Solid Tumors version 1.1. Patients We evaluated 7 patients with uHCC who received RAM as a second- or third-line treatment after LEN failure. Results The disease control rate (DCR) was 28.6% (2 of 7 patients). After the initiation of RAM, a rapid disease progression resulted in 1 patient death after 19 days. The median progression-free survival (PFS) was 41 days. There were no grade 3 or 4 treatment-related adverse events. At 6 weeks, there was no deterioration in the modified albumin-bilirubin (mALBI) grade. In patients with an imaging response of stable disease (SD), the rate of AFP production decreased from the baseline. Conclusion RAM may have a therapeutic potential for the suppression of uHCC progression in patients previously treated with LEN, as well as for maintaining the liver function during treatment. Evaluating the AFP trends may therefore be useful for predicting RAM effectiveness.

Advanced intra-tumoural structural characterisation of hepatocellular carcinoma utilising FDG-PET/CT: a comparative study of radiomics and metabolic features in 3D and 2D

PURPOSE

The aim of our work is to evaluate the correlation of two-dimensional (2D) and three-dimensional (3D) radiomics and metabolic features of hepatocellular carcinoma (HCC) with tumour diameter, staging, and metabolic tumour volume (MTV).

MATERIAL AND METHODS

Thirty-three patients with HCC were studied using 18F-fluorodeoxyglucose positron-emission tomography with computed tomography (18F [FDG] PET/CT). The tumours were segmented from the PET images after CT correction. Metabolic parameters and 35 radiomics features were compared using 2D and 3D modes. The metabolic parameters and tumour morphology were compared using 2 different types of software. Tumour heterogeneity was studied in both metabolic parameters and radiomics features. Finally, the correlation between the metabolic and radiomics features in 3D mode, as well as tumour morphology and staging according to the American Joint Committee on Cancer (AJCC) staging were studied.

RESULTS

Most of the metabolic parameters and radiomics features are statically stable through the 2D and 3D modes. Most of the 3D mode features show a correlation with metabolic parameters; the total lesion glycolysis (TLG) shows the highest correlation, with a Spearman correlation coefficient (rs) of 0.9776. Also, the grey level run length matrix/run length non-uniformity (GLRLM_RLNU) from radiomics features exhibits a correlation with a Spearman correlation coefficient of 0.9733. Maximum tumour diameter is correlated with TLG and GLRLM_RLNU, with rs equal to 0.7461 and 0.7143, respectively. Regarding AJCC staging, some features show a medium but prognostic correlation. In the case of 2D-mode features, all metabolic and radiomics features show no significant correlation with MTV, AJCC staging, and tumour maximum diameter.

CONCLUSIONS

Most of the normal metabolic parameters and radiomics features are statistically stable through the 3D and 2D modes. 3D radiomics features are significantly correlated with tumour volume, maximum diameter, and staging. Conversely, 2D features have negligible correlation with the same parameters. Therefore, 3D mode features are preferable and can accurately evaluate tumour heterogeneity.

Prognostic value of LI-RADS category on gadoxetic acid-enhanced MRI and 18F-FDG PET-CT in patients with primary liver carcinomas

OBJECTIVES

To evaluate the postoperative prognostic value of the Liver Imaging Reporting and Data System (LI-RADS) category on gadoxetic acid-enhanced MRI and 18F-fluorodeoxyglucose PET-CT in patients with primary liver carcinomas (PLCs).

METHODS

A total of 189 patients with chronic liver disease and surgically proven single PLC (42 intrahepatic cholangiocarcinomas and 21 combined hepatocellular-cholangiocarcinomas and 126 hepatocellular carcinomas [2:1 matching to non-HCC malignancies]) were retrospectively evaluated with gadoxetic acid-enhanced MRI and PET-CT. Two independent reviewers assigned an LI-RADS category for each observation. The tumor-to-liver standardized uptake value ratio (TLR) was calculated. The overall survival (OS), recurrence-free survival (RFS), and the associated factors were evaluated.

RESULTS

In multivariable analysis, LI-RADS category (LR-4 or LR-5 [LR-4/5] vs. LR-M; OS, hazard ratio [HR] 2.24, p = 0.006; RFS, HR 1.61, p = 0.028) and TLR (low, < 2.3 vs. high, ≥ 2.3; OS, HR 2.09, p = 0.014; RFS, HR 2.17, p < 0.001) were the independent factors for OS and RFS. For the LR-M group, the high TLR group showed lower OS and RFS rates than the low TLR group (OS, p = 0.008; RFS, p < 0.001). For the LR-4/5 group, the OS and RFS rates were not significantly different between the high TLR and low TLR groups (both p > 0.05).

CONCLUSIONS

Both LI-RADS category on MRI and TLR on PET-CT are associated with the postoperative prognosis of PLCs. The prognosis of PLCs classified as LR-M can be further stratified according to the TLR group, but not for the PLCs classified as LR-4/5.

KEY POINTS

• The LI-RADS category (LR-4/5 vs. LR-M) and tumor-to-liver standardized uptake value ratio (TLR, low vs. high) were independent factors for postoperative prognosis of primary liver carcinomas (PLCs). • For PLCs classified as LR-M, the TLR group helps stratify the postoperative prognosis of PLCs, with the high TLR group having a poor prognosis and the low TLR group having a better prognosis (p = 0.008 for OS and p < 0.001 for RFS). • For PLCs classified as LR-4/5, the OS and RFS rates were not significantly different between the high TLR and low TLR groups (both p > 0.05).

Predicting Hepatocellular Carcinoma Recurrence Beyond Milan Criteria After Liver Resection for Solitary Hepatocellular Carcinoma

BACKGROUND AND PURPOSE

Several hepatectomy patients with HCC who are initially transplantable (within MC) developed untransplantable HCC recurrence (beyond MC) after primary curative liver resection. The purpose of our study is to identify the risk factors of untransplantable hepatocellular carcinoma (HCC) recurrence after primary curative resection of solitary HCC and solitary HCC within Milan criteria (MC).

METHODS

We retrospectively reviewed 592 patients with recurrent HCC who underwent liver resection due to solitary HCC between 2005 and 2011.

RESULTS

All patients were Child-Pugh class A. At primary curative hepatectomy, 411 patients (69.4%) were diagnosed with HCC within MC and 181 patients (30.6%) had HCC beyond MC. The mean time from primary hepatectomy to recurrence was 14 months (range, 1-116 months). At HCC recurrence, 93 patients (15.7%) were diagnosed beyond MC. Multivariate analysis showed that microvascular invasion and a tumor grade of 3 or 4 were closely associated with a high risk of HCC recurrence beyond MC in patients who had hepatectomy for solitary HCC. Of the 411 patients within MC at primary curative hepatectomy, 54 patients (13.9%) developed HCC recurrence beyond MC. Multivariate analysis also showed that microvascular invasion and a tumor grade of 3 or 4 were closely associated with HCC recurrence beyond MC in these patients.

CONCLUSIONS

The present study suggests that the presence of certain unfavorable histological factors in patients who underwent initial liver resection of transplantable HCC within MC with good liver function predicted the development of recurrent HCC beyond MC.

Predicting tumor recurrence using metabolic indices of 18F-FDG PET/CT prior to orthotopic liver transplantationfor hepatocellular carcinoma

The present study analyzed the ability of metabolic burden indices from ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT) to predict tumor recurrence following orthotopic liver transplantation (OLT) in patients with hepatocellular carcinoma (HCC). Seven major metabolic indices were measured by ¹⁸F-FDG PET/CT in 93 patients with HCC, prior to OLT. The Mann-Whitney U test was then used to predict the association of metabolic indices, including the maximum standardized uptake value (SUVmax), tumor-to-mediastinum SUV ratio, tumor-to-normal-liver SUV ratio, SUV normalized to lean body mass metabolic tumor volume (MTV), total lesion glycolysis (TLG) and uptake-volume product (UVP), with the recurrence risk. The Deauville-like scoring system was used to quantify the recurrence risk. Univariate and multivariable Cox regression models were performed to determine survival rate. The results showed that Deauville-like score (PET-negative vs. -positive), MTV (cutoff value, 13.36), TLG (cutoff value, 62.21) and UVP (cutoff value, 66.60) had high prediction performance for tumor recurrence (P<0.05). TLG had the highest receiver operating characteristics area under the curve of 0.725. Among the clinical factors, high level of α-fetoprotein (AFP, ≥144 ng/ml), Milan criteria, tumor number (>3), involvement of both right and left lobes, and tumor size (>5 cm) were found to be significant predictors of tumor recurrence. Patients in the low metabolic group had longer recurrence-free survival (RFS) times compared with those in the high metabolic group, regardless of whether they met the Milan criteria or not. AFP, uptake-volume product according the SUV mean of mediastinum (UVP-M), Milan criteria, lymph node metastasis, and the number of tumors were significant prognostic factors for RFS (P<0.05) in both univariate and multivariate survival analyses. Additionally, the MVI was a significant prognostic factor based on univariate survival analyses. Overall, the present study demonstrated the metabolic burden indices measured by PET/CT, Deauville-like score, MTV, TLG and UVP as significant prognostic factors in patients with HCC following OLT. The combination of metabolic indices measured by PET/CT and the existing criteria, such as the Milan criteria, may play an important role in evaluating the suitability of OLT in specific patients.

18F-Fluorodeoxyglucose Uptake in Hepatocellular Carcinoma as a Useful Predictor of an Extremely Rapid Response to Lenvatinib

BACKGROUND AND AIMS

This study aimed to identify the utility of ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG-PET/CT) as a predictor of the response of hepatocellular carcinoma (HCC) to lenvatinib.

METHODS

We evaluated 28 consecutive patients with HCC diagnosed by dynamic CT or magnetic resonance imaging combined with ¹⁸F-FDG-PET/CT. The tumor-to-normal liver standardized uptake value ratio (TLR) of the target tumor was measured before treatment using ¹⁸F-FDG-PET/CT, with a TLR ≥2 classified as a high potential for malignant HCC. The treatment response was evaluated 2 weeks after the initiation of lenvatinib using modified Response Evaluation Criteria in Solid Tumors.

RESULTS

Of the 28 patients, 12 (43%) presented with a TLR ≥2. Evaluation of the treatment response at 2 weeks in these 12 patients revealed that 2 (17%) exhibited a complete response, 8 (67%) a partial response, 2 (17%) stable disease, and none with progressive disease. Therefore, 10 of the 12 patients (83%) experienced an objective response to lenvatinib. On the other hand, 7 of the 16 patients with a TLR <2 (44%) experienced an objective response. Thus, the objective response rate was higher in patients with a TLR ≥2 than in those with a TLR <2. Multivariate logistic regression analysis revealed that a TLR ≥2 (odds ratio 10.53; p = 0.028) is a useful predictor of an early objective response at 2 weeks.

CONCLUSION

Patients with unresectable HCC showed a good early treatment response to lenvatinib. High TLR (≥2) may be a useful predictor of an extremely rapid treatment response.

18F-FDG PET/CT predicts microvascular invasion and early recurrence after liver resection for hepatocellular carcinoma: A prospective observational study

BACKGROUND

This study assessed the prognostic value of 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)/computed tomography (CT) in the prediction of MVI and early recurrence following resection.

METHOD

This prospective study (ClinicalTrials.gov ID: NCT02145013) included 78 consecutive HCC patients who underwent 18F-FDG PET/CT before curative-intent resection from 2014 to 2017. Prognostic factors available before surgery for predicting MVI and early recurrence (≤2 years) were identified by univariate and multivariate analyses.

RESULTS

The 18F-FDG PET/CT result was positive in 30 (38%) patients. MVI was present in 33% (26/78) of specimens. Early recurrence occurred in 19% (14/74) of surviving patients. PET/CT positivity was the sole independent predictor of MVI (odds ratio [OR] = 3.6, 95% confidence interval [CI] = 1.1-11.2; p = 0.03), with a specificity and sensitivity for predicting MVI of 73% and 62%, respectively. Analysis of variables available before surgery showed that PET/CT positivity (hazard ratio [HR] = 5.8, 95% CI = 1.6-20.4; p = 0.006) and the male sex (HR = 6.6; 95% CI = 1.8-24.2; p = 0.005) were independent predictors of early recurrence.

CONCLUSION

18F-FDG PET/CT predicts MVI and early recurrence after surgery for HCC and could be used to select patients for neoadjuvant treatment.

Emerging role of 18F-fluorodeoxyglucose positron emission tomography for guiding management of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of major causes of cancer mortality worldwide. For decades, ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography (PET) has been widely used for staging, predicting prognosis, and detecting cancer recurrence in various types of malignant diseases. Due to low sensitivity of FDG PET for detecting intrahepatic HCC lesions, the clinical value of FDG PET in HCC patients has been limited. However, recent studies with diverse analytic methods have shown that FDG PET has promising role in aiding management of HCC patients. In this review, we will discuss the clinical role of FDG PET for staging, predicting prognosis, and evaluating treatment response in HCC. Further, we will focus on recent clinical studies regarding implication of volumetric FDG PET parameters, the significance of FDG uptake in HCC for selecting treatment and predicting treatment response, and the use of radiomics of FDG PET in HCC.

18F-fludeoxyglucose positron emission tomography for diagnosis of HCC: implications for therapeutic strategy in curative and non-curative approaches

Hepatocellular carcinoma (HCC) is a global health issue with increasing incidence and high mortality rate. Depending on the tumor load and extent of underlying liver cirrhosis, aggressive surgical treatment by hepatectomy or liver transplantation (LT) may lead to cure, whereas different modalities of liver-directed locoregional or systemic tumor treatments are currently available for a noncurative approach. Apart from tumor burden and grade of liver dysfunction, assessment of prognostic relevant biological tumor aggressiveness is vitally important for establishing a promising multimodal therapeutic strategy and improving the individual treatment-related risk/benefit ratio. In recent years, an increasing body of clinical evidence has been presented that ¹⁸F-fludeoxyglucose (¹⁸F-FDG) positron emission tomography (PET), which is a standard nuclear imaging device in oncology, may serve as a powerful surrogate for tumor invasiveness and prognosis in HCC patients and, thereby, impact individual decision making on most appropriate therapy concept. This review describes the currently available data on the prognostic value of ¹⁸F-FDG PET in patients with early and advanced HCC stages and the resulting implications for treatment strategy.

Prognostic Prediction Models for Resection of Large Hepatocellular Carcinoma: A Korean Multicenter Study

BACKGROUND

We developed a prognostic prediction model (PPM) using 4 factors for hepatic resection (HR) of large hepatic cellular carcinoma (HCC). Multiplication of α-fetoprotein (AFP), des-γ-carboxy prothrombin, and tumor volume (TV) (ADV score) is a surrogate marker for post-resection prognosis. This study intended to validate the predictive power of 4-factor PPM and to develop new ADV score-based PPM.

METHODS

A total of 526 patients who underwent HR for solitary HCC ≥ 8 cm were selected from 9 Korean institutions between 2008 and 2014.

RESULTS

Median tumor diameter and TV were 11.0 cm and 398 mL, respectively. Tumor recurrence and patient survival rates were 53.0 and 78.4% at 1 year and 70.2 and 49.3% at 5 years, respectively. Independent risk factors for both tumor recurrence and patient survival included AFP ≥ 100 ng/mL, hypermetabolic FDG-positron emission tomography (PET), microvascular invasion and satellite nodules, which comprised 4 factors of the PPM. Five subgroups based on the number of involved risk factors exhibited significant differences in tumor recurrence and patient survival. ADV score cutoff was set at 7log (ADV7log) after cluster prognostic analysis. Patient grouping according to combination of ADV7log and FDG-PET findings (ADV7log-PET) exhibited significant differences in tumor recurrence and patient survival, comparable to those of the 4-factor PPM.

CONCLUSIONS

Two PPMs using 4 risk factors and ADV7log-PET could reliably predict the risk of early HCC recurrence and long-term survival outcomes in patients who underwent HR for large HCC. We believe that these PPMs can guide surgical treatment for large HCCs from preoperative HR planning to post-resection follow-up.

Proposal of a New Preoperative Prognostic Model for Solitary Hepatocellular Carcinoma Incorporating 18F-FDG-PET Imaging with the ALBI Grade

BACKGROUND

Existing prognostic systems were not developed using only objective variables available preoperatively, and therefore do not provide ideal prognostication for patients undergoing hepatectomy for hepatocellular carcinoma (HCC). We aimed to develop a preoperative prognostic model using objective variables involving two parameters: ¹⁸F-fluorodeoxyglucose-positron emission tomography (¹⁸F-FDG-PET) and the albumin-bilirubin (ALBI) grade.

METHODS

This study included 207 consecutive patients with solitary HCC who underwent ¹⁸F-FDG-PET prior to hepatectomy. The tumor to non-tumor maximum standardized uptake value ratio (TNR) was used as an ¹⁸F-FDG PET imaging parameter.

RESULTS

The 5-year overall survival (OS) and disease-free survival (DFS) rates were 58.6% and 28.8%, respectively. Multivariate analysis of OS identified TNR ≥ 2 (hazard ratio [HR] 1.743, 95% confidence interval [CI] 1.114-2.648, p = 0.016) and ALBI grade 2 (HR 1.966, 95% CI 1.349-2.884, p < 0.001) as the only significant prognostic factors; tumor diameter and tumor markers were not significant. Patients were divided into low- (TNR < 2 and ALBI grade 1), intermediate- (TNR < 2 and ALBI grade 2, or TNR ≥ 2 and ALBI grade 1), and high-risk (TNR ≥ 2 and ALBI grade 2) groups, which differed significantly in terms of survival (5-year OS: 75.7, 49.6, and 27.3%, respectively, p < 0.001; 5-year DFS: 37.0, 24.9, and 13.6%, respectively, p < 0.001). Compared with other staging systems, our model had the best discriminatory ability (corrected Akaike information criteria 1054.8, p < 0.001) and homogeneity (likelihood ratio Chi square value 27.6, p < 0.001).

CONCLUSION

A preoperative prognostic model incorporating ¹⁸F-FDG-PET imaging with the ALBI grade may be useful for estimating the prognosis of selected patients with solitary HCC.

18F-fluorodeoxyglucose uptake of hepatocellular carcinoma as a prognostic predictor in patients with sorafenib treatment

PURPOSE

Sorafenib, an oral multikinase inhibitor, is a recommended treatment option available for patients with Barcelona Clinic Liver Cancer (BCLC)-C stage hepatocellular carcinoma (HCC). This study aimed to evaluate the performance of ¹⁸F-fluorodeoxyglucose positron emission tomography (¹⁸F-FDG PET) for predicting tumour progression during sorafenib treatment.

METHODS

We formed a retrospective cohort comprising patients treated with sorafenib for at least 30 days and undergoing ¹⁸F-FDG PET/CT within 1 month before treatment. For statistical analyses, the tumour-to-liver standardised uptake value (SUV) ratio (TLR) of the most hypermetabolic lesion was measured.

RESULTS

Among a total of 35 patients, two obtained partial remission, and 11 showed stable disease after the first response evaluation. Patients with a TLR ≥ 2.9 (n = 17) had a median overall survival (OS) of 3.7 months after sorafenib treatment, whereas patients with a TLR < 2.9 (n = 18) had median OS of 12.2 months (P < 0.001), although the disease control rate was not significantly different between the two groups. Pretreatment TLR ≥ 2.9 (hazard ratio [HR] = 6.318, P = 0.002) and Child-Pugh class B (HR = 4.316, P = 0.044) were poor prognostic factors for OS, and a TLR ≥ 2.9 (HR = 2.911, P = 0.024) was the only poor prognostic factor for progression-free survival in a multivariate analysis.

CONCLUSION

Pretreatment tumour metabolic activity assessed by ¹⁸F-FDG PET is an independent prognostic factor for survival in patients with BCLC-C stage HCC receiving sorafenib monotherapy, although it may not predict tumour response to the treatment.

Identification of keratin 19-positive cancer stem cells associating human hepatocellular carcinoma using CYFRA 21-1

The current lack of an easily measurable surrogate marker of cancer stem cells (CSCs) prevents the clinical application of CSCs for hepatocellular carcinoma (HCC). We previously reported that keratin 19 (K19) is a novel HCC‐CSC marker associated with transforming growth factor beta (TGFβ)/Smad signaling, and that K19⁺ HCC‐CSCs could be a new therapeutic target of TGFβ receptor 1 inhibitor LY2157299. In this study, we examined whether K19⁺ HCC‐CSCs can be tracked using cytokeratin 19 fragment CYFRA 21‐1. In 147 HCC patients who underwent curative resection and evaluated K19 expression by immunohistochemistry, preoperative serum CYFRA 21‐1 levels were significantly higher in K19⁺ patients than in K19⁻ patients (P < 0.01). Receiver operating characteristic analyses revealed that serum CYFRA 21‐1 was the statistically significant and the most sensitive predictor of tumor K19 expression among preoperative laboratory test values (P < 0.001). In HCC cells encoding with a K19 promoter‐driven enhanced green fluorescent protein, fluorescence‐activated cell sorting (FACS)‐isolated K19⁺ cells displayed significantly higher levels of supernatant CYFRA 21‐1 than K19⁻ cells (P < 0.01). Gain/loss of K19 function experiments confirmed that CYFRA 21‐1 levels were regulated by K19 function in HCC cells. Furthermore, CYFRA 21‐1 levels reflected the treatment efficacy of LY2157299 in K19⁺ cells. In conclusion, CYFRA 21‐1 can be used to predict K19 expression in HCC, and should thereby aid in the development of novel therapeutic strategies targeting K19⁺ HCC‐CSCs.

18F-FDG-PET for Assessing Biological Viability and Prognosis in Liver Transplant Patients with Hepatocellular Carcinoma

Liver transplantation (LT) has become standard of care in patients with non-resectable early stage hepatocellular carcinoma (HCC) in liver cirrhosis. Currently, patient selection for LT is strictly based on tumor size and number, provided by the Milan criteria. This may, however, exclude patients with advanced tumor load but favourable biology from a possibly curative treatment option. It became clear in recent years that biological tumor viability rather than tumor macromorphology determines posttransplant outcome. In particular, microvascular invasion and poor grading reflect tumor aggressiveness and promote the risk of tumor relapse. Pretransplant biopsy is not applicable due to tumor heterogeneity and risk of tumor cell seeding. ¹⁸F-fludeoxyglucose (¹⁸F-FDG) positron emission tomography (PET), an established nuclear imaging device in oncology, was demonstrated to non-invasively correlate with unfavorable histopathologic features. Currently, there is an increasing amount of evidence that ¹⁸F-FDG-PET is very useful for identifying eligible liver transplant patients with HCC beyond standard criteria but less aggressive tumor properties. In order to safely expand the HCC selection criteria and the pool of eligible liver recipients, tumor evaluation with ¹⁸F-FDG-PET should be implemented in pretransplant decision process.

Preoperative platelet-to-lymphocyte ratio can predict recurrence beyond the Milan criteria after hepatectomy for patients with hepatocellular carcinoma

AIM

Postoperative recurrence beyond the Milan criteria is a poor prognostic factor for patients with hepatocellular carcinoma (HCC) treated with various therapies. We investigated the most useful inflammation-based prognostic score for predicting recurrence beyond the Milan criteria after initial liver resection.

METHODS

From January 2007 to December 2012, 271 consecutive patients with HCC who underwent curative liver resection were enrolled. Patients were divided according to the initial recurrence pattern: recurrence beyond the Milan criteria; and recurrence within the Milan criteria, or no recurrence. The patients were classified into two groups, low platelet-to-lymphocyte ratio (PLR) (<150) and high PLR (≥150), additionally using other inflammation-based prognostic scores. Then we analyzed the association between the recurrence patterns and the clinicopathological factors including PLR.

RESULTS

Fifty-five (20.2%) patients had recurrence beyond the Milan criteria. The 5-year survival rate in patients with recurrence beyond the Milan criteria (41.6%) was significantly lower than in those with other recurrence patterns (79.7%). High PLR level was observed in 15.5% of the patients. Multivariate analysis revealed that PLR was the only independent predictive factor of recurrence patterns (odds ratio, 2.55; 95% confidence interval, 1.17-5.49; P = 0.018). The high PLR level was significantly associated with higher serum des-γ-carboxy prothrombin level, larger tumor size, and poor histological differentiation.

CONCLUSION

Among several inflammatory indices, PLR is a good indicator to predict recurrence beyond the Milan criteria after liver resection for patients with HCC.

Volumetric parameters on FDG PET can predict early intrahepatic recurrence-free survival in patients with hepatocellular carcinoma after curative surgical resection

PURPOSE

This study assessed the prognostic values of volumetric parameters on ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography (PET) in predicting early intrahepatic recurrence-free survival (RFS) after curative resection in patients with hepatocellular carcinoma (HCC).

METHODS

A retrospective analysis was performed on 242 patients with HCC who underwent staging FDG PET and subsequent curative surgical resection. The tumor-to-non-tumorous liver uptake ratio, metabolic tumor volume (MTV), and total lesion glycolysis (TLG) of the HCC lesions on PET were measured. The prognostic values of clinical factors and PET parameters for predicting overall RFS, overall survival (OS), extrahepatic RFS, and early and late intrahepatic RFS were assessed.

RESULTS

The median follow-up period was 54.7 months, during which 110 patients (45.5%) experienced HCC recurrence and 62 (25.6%) died. Patients with extrahepatic and early intrahepatic recurrence showed worse OS than did those with no recurrence or late intrahepatic recurrence (p < 0.001). Serum bilirubin level, MTV, and TLG were independent prognostic factors for overall RFS and OS (p < 0.05). Only MTV and TLG were prognostic for extrahepatic RFS (p < 0.05). Serum alpha-fetoprotein and bilirubin levels, MTV, and TLG were prognostic for early intrahepatic RFS (p < 0.05) and hepatitis C virus (HCV) positivity and serum albumin level were independently prognostic for late intrahepatic RFS (p < 0.05).

CONCLUSION

Intrahepatic recurrence showed different prognoses according to the time interval of recurrence in which early recurrence had as poor survival as extrahepatic recurrence. MTV and TLG on initial staging PET were significant independent factors for predicting early intrahepatic and extrahepatic RFS in patients with HCC after curative resection. Only HCV positivity and serum albumin level were significant for late intrahepatic RFS, which is mainly attributable to the de novo formation of new primary HCC.

Patients with early recurrence of hepatocellular carcinoma have poor prognosis

BACKGROUND

Early recurrence (ER) after hepatic resection (HR) is a poor prognostic factor for patients with hepatocellular carcinoma (HCC). This study aimed to identify the clinicopathological features, outcomes, and risk factors for ER after HR for small HCC in order to clarify the reasons why ER is a worse recurrence pattern.

METHODS

We retrospectively examined 130 patients who underwent HR for small HCC (≤30 mm). Recurrence was classified into ER (<2 years) and late recurrence (LR) (≥2 years). The clinicopathological features, outcomes, and risk factors for ER were analyzed by multivariate analysis.

RESULTS

ER was observed in 39 patients (30.0%). The survival rate of the ER group was significantly lower than that of the LR group (P<0.005), and ER was an independent prognostic factor for poor survival (P=0.0001). The ER group had a significantly higher frequency (P=0.0039) and shorter interval (P=0.027) of development to carcinoma beyond the Milan criteria (DBMC) compared with the LR group, and ER was an independent risk factor for DBMC (P<0.0001). Multi-nodularity, non-simple nodular type, and microvascular invasion were independent predictors for ER (P=0.012, 0.010, and 0.019, respectively).

CONCLUSIONS

ER was a highly malignant recurrence pattern associated with DBMC and subsequent poor survival after HR for small HCC. Multi-nodularity, non-simple nodular type, and microvascular invasion predict ER, and taking these factors into consideration may be useful for the decision of the treatment strategy for small HCC after HR.

Combination of FDG-PET and UCSF Criteria for Predicting HCC Recurrence After Living Donor Liver Transplantation

BACKGROUND

F-18 fluorodeoxyglucose (FDG) uptake in hepatocellular carcinoma (HCC) is related to tumor biology and has predictive value for tumor recurrence after liver transplantation. This retrospective study assessed whether the degree of FDG uptake in positron emission tomography (PET) can be used to predict HCC recurrence after living donor liver transplantation (LDLT).

METHODS

One hundred forty-seven patients with HCC underwent FDG-PET studies before LDLT. The semiquantification of FDG uptake in FDG-positive HCC was done with maximum standardized uptake value (SUVmax) and tumor to nontumor ratio (TNR). Recurrence-free survivals (RFS) were calculated using the Kaplan-Meier method.

RESULTS

In univariable analysis, T stage, presence of microvascular invasion, being FDG-positive, SUVmax, and TNR were significant predictors for worse RFS. The optimal cutoff values of SUVmax and TNR were 4.8 and 2.0, respectively. The high FDG uptake HCC (TNR ≥ 2) was a strong predictor for worse RFS (hazard ratio, 13.52; 95% confidence interval, 4.77-38.29; P < 0.001). Using a combination of FDG-PET and University of California San Francisco (UCSF) criteria, the patients can be divided into low-risk (within UCSF criteria and FDG-negative), intermediate-risk (beyond UCSF criteria and FDG-negative; FDG-positive and TNR < 2), and high-risk (FDG-positive and TNR ≥ 2) groups. The estimated 5-year RFS in these groups were 85.5%, 83.9%, and 29.6% according to the combination of FDG-PET and clinical UCSF criteria, and 94.0%, 75.8%, and 29.6% according to the combination of FDG-PET and pathologic UCSF criteria, respectively.

CONCLUSIONS

Combination of FDG-PET and UCSF criteria can be used to predict the risk of HCC recurrence after LDLT.

Preoperative Fluorine 18 Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography for Prediction of Microvascular Invasion in Small Hepatocellular Carcinoma

OBJECTIVES

This study aimed to assess the value of preoperative fluorine 18 fluorodeoxyglucose positron emission tomography/computed tomography (F-FDG PET-CT) for predicting microvascular invasion (MVI) in small hepatocellular carcinoma (HCC).

METHODS

We retrospectively examined 60 patients who received F-FDG PET-CT prior to hepatic resection for small HCC (≤30 mm) with subsequent MVI confirmation by histopathology. The associations between PET-positive status and tumor factors were assessed. Furthermore, independent predictors for MVI and diagnostic utility of each MVI predictor were assessed.

RESULTS

Multivariate analysis revealed the presence of MVI as an independent predictor of PET-positive status (P = 0.023). Maximum standardized uptake value (SUVmax) of 3.2 or greater (P = 0.017) and lens culinaris agglutinin a-reactive α-fetoprotein (AFP-L3) 19% or greater (P = 0.010) were independent predictors of MVI. Areas under the receiver operating characteristic curves for SUVmax of 3.2 or greater, AFP-L3 19% or greater, and both factors combined for predicting MVI were 0.712 (0.493-0.932), 0.755 (0.563-0.947), and 0.856 (0.721-0.991), respectively. The sensitivity and specificity for predicting MVI were 77.8% and 74.5% for SUVmax of 3.2 or greater, 66.7% and 84.3% for AFP-L3 19% or greater, and 88.9% and 82.4% for the combination.

CONCLUSIONS

F-FDG PET-CT and AFP-L3 may be useful for predicting MVI in small HCC, and the combination of the 2 factors provided reliable assessment for selection of suitable hepatic resection and liver transplantation candidates.

Prognostic Value of Metabolic Tumor Volume and Total Lesion Glycolysis on Preoperative 18F-FDG PET/CT in Patients With Very Early and Early Hepatocellular Carcinoma

PURPOSE

The aim of this article was to evaluate the prognostic value of metabolic tumor volume (MTV) and total lesion glycolysis (TLG) on preoperative F-FDG PET/CT for predicting intrahepatic recurrence-free survival (IHRFS), extrahepatic metastasis-free survival (EHMFS), and overall survival (OS) in patients with very early/early hepatocellular carcinoma (HCC).

PATIENTS AND METHODS

We retrospectively enrolled 132 patients with very early/early HCC who underwent F-FDG PET/CT followed by surgery. The maximum tumor SUV-to-mean normal liver SUV ratio, MTV, and TLG were measured for each patient. Prognostic significances of PET/CT parameters and clinicopathologic factors for IHRFS, EHMFS, and OS were evaluated. Cumulative IHRFS, EHMFS, and OS were calculated using the Kaplan-Meier method.

RESULTS

Thirty-three (25%) and 21 (15.9%) of 132 patients experienced intrahepatic and extrahepatic recurrence, respectively, during a median follow-up period of 38.1 months. In multivariate analysis, none of the factors were significant for IHRFS. Metabolic tumor volume and TLG were only significant factors for EHMFS and OS (P < 0.05). The 5-year EHMFS rates were 94.8% in patients with low MTV and TLG, and 62.1% and 63.2% in patients with high MTV and TLG, respectively (P < 0.001). The 5-year OS rates were 92.6% and 92.4% in patients with low MTV and TLG, and 63.3% and 64.3% in patients with high MTV and TLG, respectively (P < 0.001).

CONCLUSIONS

Metabolic tumor volume and TLG on preoperative PET/CT were independent prognostic factors for EHMFS and OS but not IHRFS in patients with very early/early HCC. Therefore, patients with high MTV or TLG should be closely observed for extrahepatic metastasis using systemic evaluations.

Identification of Keratin 19-Positive Cancer Stem Cells Associating Human Hepatocellular Carcinoma Using 18F-Fluorodeoxyglucose Positron Emission Tomography

Purpose: The current lack of tools for easy assessment of cancer stem cells (CSC) prevents the development of therapeutic strategies for hepatocellular carcinoma (HCC). We previously reported that keratin 19 (K19) is a novel HCC-CSC marker and that PET with ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) is an effective method for predicting postoperative outcome in hepatocellular carcinoma. Herein, we examined whether K19⁺ HCC-CSCs can be tracked using ¹⁸F-FDG-PET.Experimental Design: K19 and glucose transporter-1 (GLUT1) expression was evaluated by IHC in 98 hepatocellular carcinoma patients who underwent ¹⁸F-FDG-PET scans before primary tumor resection. Standardized uptake values (SUV) for primary tumors and tumor-to-nontumor SUV ratios (TNR) were calculated using FDG accumulation levels, and values were compared among K19⁺/K19^- patients. Using hepatocellular carcinoma cell lines encoding with a K19 promoter-driven enhanced GFP, ¹⁸F-FDG uptake and GLUT1 expression were examined in FACS-isolated K19⁺/K19^- cells.Results: In hepatocellular carcinoma patients, K19 expression was significantly correlated with GLUT1 expression and FDG accumulation. ROC analyses revealed that among preoperative clinical factors, TNR was the most sensitive indicator of K19 expression in hepatocellular carcinoma tumors. In hepatocellular carcinoma cells, FACS-isolated K19⁺ cells displayed significantly higher ¹⁸F-FDG uptake than K19^- cells. Moreover, gain/loss-of-function experiments confirmed that K19 regulates ¹⁸F-FDG uptake through TGFβ/Smad signaling, including Sp1 and its downstream target GLUT1.Conclusions:¹⁸F-FDG-PET can be used to predict K19 expression in hepatocellular carcinoma and should thereby aid in the development of novel therapeutic strategies targeting K19⁺ HCC-CSCs. Clin Cancer Res; 23(6); 1450-60. ©2016 AACR.

Prognostic value of (18)F-fluorodeoxyglucose positron emission tomography/computed tomography in patients with Barcelona Clinic Liver Cancer stages 0 and A hepatocellular carcinomas: a multicenter retrospective cohort study

PURPOSE

We evaluated the prognostic value of pretreatment (18)F-fluorodeoxyglucose positron emission tomography with computed tomography (FDG PET/CT) in patients with Barcelona Clinic Liver Cancer (BCLC) stage 0 or A hepatocellular carcinoma (HCC) who had received curative treatment or transarterial chemoembolization (TACE).

METHODS

Between 2009 and 2010, 317 patients diagnosed with HCC at seven hospitals were enrolled. Among these, 195 patients underwent curative treatments including resection, liver transplantation, and radiofrequency ablation. TACE was performed in 122 patients. The tumor-to-normal liver standardized uptake value ratio (TLR) of the primary tumor was measured using pretreatment FDG PET/CT. The prognostic significance of TLR and other clinical variables was assessed using Cox regression models. Differences in the overall survival (OS) associated with TLR or other significant clinical factors were examined using the Kaplan-Meier method.

RESULTS

Over a median follow-up period of 46 months, 77 patients died from cancer. In the curative cohort, higher TLR (≥2) was significantly associated with death (hazard ratio [HR] = 2.68; 95 % CI, 1.16-6.15; P = 0.020) in multivariable analysis. Patients with a higher TLR had significantly worse OS than patients with a lower TLR (5-year overall survival, 61 % vs. 79.4 %; P = 0.006). In the TACE cohort, the Model for End-Stage Liver Disease (MELD) score (≥8) was a significant independent prognostic factor for OS (HR = 3.34; 95 % CI, 1.49-7.48; P = 0.003), whereas TLR was not associated with OS. The Kaplan-Meier curves showed significantly poorer OS in patients with higher MELD scores (≥8) than in those with lower MELD scores (5-year survival rate, 33.1 % vs. 79.6 %; P < 0.001).

CONCLUSIONS

Pretreatment TLR measured using FDG PET/CT was an independent prognostic factor for OS in patients with BCLC stage 0 or A HCC undergoing curative treatment. In contrast, underlying liver function appeared to be important in predicting the prognosis of patients undergoing TACE.

Prognostic significance of parameters from pretreatment (18)F-FDG PET in hepatocellular carcinoma: a meta-analysis

PURPOSE

The prognostic value of (18)F-deoxyglucose positron emission tomography ((18)F-FDG PET) on hepatocellular carcinoma (HCC) remains inconclusive. This study aims to investigate the prognostic role of pretreatment (18)F-FDG PET on HCC patients by meta-analysis.

METHODS

PubMed, Embase, Cochrane library, and Wanfang databases were searched until June 2015. Hazard ratios (HRs) with corresponding 95% confidence intervals (CIs) were synthesized by Stata 10.0, and the combined results were used as effective values.

RESULTS

Twenty-two studies containing a total of 1721 patients were identified. According to random-effect model, meta-analysis results showed that high Tumor SUV/Liver SUV (Tsuv/Lsuv) ratio was significantly associated with poorer overall survival (OS) (HR = 2.04; 95% CI 1.50-2.79; P = 0.000) and poorer disease-free survival (HR = 7.17; 95% CI 3.58-14.36; P = 0.000); and high Tumor SUV (Tsuv) value was also correlated with poor OS (HR = 1.53; 95% CI 1.26-1.87; P = 0.000). Meanwhile, subgroup analysis results showed that the significant association above was not altered by study sample size, parameter cutoff value, analytic method, and follow-up period, but there was no significant association between Tsuv/Lsuv ratio and OS in patients who underwent resection (HR = 1.71; 95% CI 1.00-2.92; P = 0.052).

CONCLUSIONS

Both high Tsuv/Lsuv ratio and high Tsuv value are associated with poor prognosis in HCC patients. Therefore, pretreatment (18)F-FDG PET is a useful tool in predicting the prognosis of HCC patients. More studies with explicit treatment modalities are required to investigate the prognostic value of pretreatment (18)F-FDG PET on HCC patients.

The Impact of Tumor Size on Long-Term Survival Outcomes After Resection of Solitary Hepatocellular Carcinoma: Single-Institution Experience with 2558 Patients

BACKGROUND

According to the 7th AJCC TNM staging system, solitary hepatocellular carcinoma (HCC) is classified as T1 or T2 based on microvascular invasion (MVI) regardless of tumor size. This study intended to evaluate the prognostic impact of tumor size on survival outcomes after macroscopic curative resection of solitary HCC.

METHODS

Patients who underwent R0 resection of solitary HCC <10 cm (n = 2558) were selected for study. Follow-up lasted ≥24 months or until death.

RESULTS

HCC was detected during regular health screening or routine follow-up in 2054 cases (80.3%). Hepatitis B virus (HBV) infection was associated in 2127 (83.2%). Mean patient age was 54.4 ± 9.9 years. Anatomical resection was performed in 1786 (69.8%). MVI was identified in 407 (16.0%) which therefore became stage T2; the other 2150 became stage T1. Tumor recurrence and patient survival rates were 24.9 and 95.0% after 1 year, 49.6 and 84.1% after 3 years, 57.7 and 75.0 % after 5 years, and 67.3 and 56.6% after 10 years, respectively. Multivariate analysis showed that non-anatomical resection, MVI, and tumor size >5 cm were independent risk factors for both tumor recurrence and overall patient survival. Long-term survival correlated negatively with tumor size and MVI. Subgroup analysis with MVI and size cutoff of 5 cm revealed a significant survival difference (p = 0.000). Tumor size >5 cm was not a significant prognostic factor in non-HBV patients.

CONCLUSIONS

These results suggest that the prognostic impact of tumor size may be underestimated in the current version of the AJCC staging system and that solitary HCC staging could be improved with inclusion of tumor size cutoff of 5 cm in HBV-associated patients. Further validation is necessary with multicenter studies.

The predictive value of metabolic tumor volume on FDG PET/CT for transarterial chemoembolization and transarterial chemotherapy infusion in hepatocellular carcinoma patients without extrahepatic metastasis

OBJECTIVE

The aim of this study was to evaluate the prognostic value of metabolic tumor volume (MTV) on pre-treatment F-18 fluorodeoxyglucose (FDG) PET/CT in patients with hepatocellular carcinoma (HCC).

METHODS

A total of 59 HCC patients who underwent FDG PET/CT before transarterial chemoembolization (TACE) or transarterial chemotherapy infusion (TACI) were retrospectively enrolled. The region of interest was drawn in the HCC and normal liver tissue. MTV2SD, defined as the sum of the voxels with higher standardized uptake values (SUV) than the SUV of the 97.5th percentile of voxels of the normal liver for each patient, was calculated using an intensity-volume histogram (IVH). The ratio of the maximum SUV of the tumor to the mean SUV of normal liver (T max/L mean) was also calculated. The prognostic significance of MTV2SD and Tmax/Lmean for progression-free survival (PFS) and overall survival (OS) was evaluated along with other clinical factors.

RESULTS

The tumor number, Tmax/Lmean, and MTV2SD were significant prognostic factors affecting PFS (p < 0.05), whereas tumor number, serum alpha-fetoprotein level, tumor stage, portal vein thrombosis, Tmax/Lmean, and MTV2SD were significant prognostic factors for OS (p < 0.05). In multivariate analysis, the tumor number and MTV2SD were independent prognostic factors for PFS (p < 0.05), whereas the independent prognostic factors for OS were tumor number, tumor stage, and MTV2SD (p < 0.05). The mean PFS and OS in patients with low MTV2SD (15.4 and 63.1 months, respectively) were significantly longer than those in patients with high MTV2SD (6.0 and 15.2 months, respectively; p = 0.005 and p < 0.0001, respectively).

CONCLUSIONS

Metabolic tumor volume was an independent prognostic factor for PFS and OS in patients with HCC. Therefore, FDG PET/CT can provide valuable prognostic information for HCC patients who undergo TACE or TACI.

Evaluation of prognostic factors on recurrence after curative resections for hepatocellular carcinoma

AIM: To select appropriate patients before surgical resection for hepatocellular carcinoma (HCC), especially those with advanced tumors.

METHODS: From January 2000 to December 2012, we retrospectively analyzed the medical records of 298 patients who had undergone surgical resections for HCC with curative intent at our hospital. We evaluated preoperative prognostic factors associated with histologic grade of tumor, recurrence and survival, especially the findings of pre-operative imaging studies such as positron emission tomography-computed tomography (PET-CT) and magnetic resonance imaging (MRI). And then, we established a scoring system to predict recurrence and survival after surgery dividing the patients into two groups based on a tumor size of 5 cm.

RESULTS: Of the 298 patients, 129 (43.3%) developed recurrence during the follow-up period. The 5 year disease free survival and overall survival were 47.0% and 58.7% respectively. In multivariate analysis, a serum alpha-fetoprotein (AFP) level of > 100 ng/mL and a standardized uptake value (SUV) of PET-CT of > 3.5 were predictive factors for histologic grade of tumor, recurrence, and survival. Tumor size of > 5 cm and a relative enhancement ratio (RER) calculated from preoperative MRI were also significantly associated with prognosis in univariate analysis. We established a scoring system to predict prognosis using AFP, SUV, and RER. In those with tumors of > 5 cm, it showed predicted both recurrence (P = 0.005) and survival (P = 0.001).

CONCLUSION: The AFP, tumor size, SUV and RER are useful for prognosis preoperatively. An accurate prediction of prognosis is possible using our scoring system in large size tumors.

[18F]Fluorodeoxyglucose PET/Computed Tomography in Gastrointestinal Malignancies

This article discusses the current state-of-the-art application of 2-deoxy-2-[(18)F]fluoro-d-glucose (FDG)-PET and FDG-PET/computed tomography (CT) in the management of patients with gastrointestinal malignancies. Gastrointestinal malignancies include many different cell types, several common malignancies of which may be imaged by FDG-PET/CT. This review focuses on gastric carcinoma, pancreatic carcinoma, hepatocellular carcinoma, cholangiocarcinoma, colorectal carcinoma, and stroma cell tumors. The role of FDG-PET/CT in staging these malignancies is discussed, in addition to (re)staging, detection of recurrent disease, patient selection/prognostication, and response assessment, using the currently available literature.

[18F]Fluorodeoxyglucose PET for Interventional Oncology in Liver Malignancy

[(18)F]Fluorodeoxyglucose (FDG) PET is a functional imaging tool that provides metabolic information, which has the potential to detect a lesion before it becomes anatomically apparent. This ability constitutes a strong argument for using FDG-PET/computed tomography (CT) in the management of oncology patients. Many studies have investigated the accuracy of FDG-PET or FDG-PET/CT for these purposes, but with small sample sizes based on retrospective cohorts. This article provides an overview of the role of FDG-PET or FDG-PET/CT in patients with liver malignancies treated by means of surgical resection, ablative therapy, chemoembolization, radioembolization, and brachytherapy, all being liver-directed oncologic interventions.

Positron emission tomography in malignancies of the liver, pancreas and biliary tract - indications and potential pitfalls

Abstract Malignancies of the hepato-pancreatico-biliary (HPB) system are relatively common and generally characterized by a dismal prognosis. Positron emission tomography (PET) is a functional imaging technique that has emerged as an important modality in oncological decision-making. The principal radiopharmaceutical in PET imaging is the glucose analog (18)F-fluorodeoxyglucose, which is able to detect altered glucose metabolism in malignant tissue. PET is typically used in conjunction with computed tomography (CT), and previous studies have supported several uses of PET/CT in HPB malignancies, including staging, differential diagnostics and monitoring of treatment response and progress of disease. A review of PET/CT in the context of HPB malignancies will be presented, including indications and potential pitfalls.

Hepatocellular carcinoma and gastroenteropancreatic neuroendocrine tumors: potential role of other positron emission tomography radiotracers

18F-Fluorodeoxyglucose avidity for gastroenteropancreatic neuroendocrine tumors and hepatocellular carcinoma is variable, depending on the underlying tumor biology. Experience with non-fluorodeoxyglucose (FDG) tracers (eg, 18F-labeled amine precursors l-dihydroxyphenylalanine and 68Ga-DOTA-peptides for gastroenteropancreatic neuroendocrine tumors and radiolabeled acetate or choline for hepatocellular carcinoma) is evolving and expanding rapidly. This article reviews the role of FDG and non-FDG radiotracers in the imaging evaluation of patients with gastroenteropancreatic neuroendocrine tumors or hepatocellular carcinoma.

Choline kinase alpha and hexokinase-2 protein expression in hepatocellular carcinoma: association with survival

Purpose

Hexokinase-2 (HK2) and more recently choline kinase alpha (CKA) expression has been correlated with clinical outcomes in several major cancers. This study examines the protein expression of HK2 and CKA in hepatocellular carcinoma (HCC) in association with patient survival and other clinicopathologic parameters.

Methods

Immunohistochemical analysis for HK2 and CKA expression was performed on a tissue microarray of 157 HCC tumor samples. Results were analyzed in relation to clinicopathologic data from Surveillance, Epidemiology, and End-Results Program registries. Mortality rates were assessed by Kaplan-Meier estimates and compared using log-rank tests. Predictors of overall survival were assessed using proportional hazards regression. RESULTS: Immunohistochemical expression of HK2 and CKA was detected in 71 (45%) and 55 (35%) tumor samples, respectively. Differences in tumor HK2 expression were associated with tumor grade (p = 0.008) and cancer stage (p = 0.001), while CKA expression differed significantly only across cancer stage (p = 0.048). Increased mortality was associated with tumor HK2 expression (p = 0.003) as well as CKA expression (p = 0.03) with hazard ratios of 1.86 (95% confidence interval (CI) 1.23–2.83) and 1.59 (95% CI 1.04–2.41), respectively. Similar effects on overall survival were noted in a subset analysis of early stage (I and II) HCC. Tumor HK2 expression, but not CKA expression, remained a significant predictor of survival in multivariable analyses.

Conclusion

HK2 and CKA expression may have biologic and prognostic significance in HCC, with tumor HK2 expression being a potential independent predictor of survival.

A pilot comparison of 18F-fluorodeoxyglucose and 18F-fluorocholine PET/CT to predict early recurrence of unifocal hepatocellular carcinoma after surgical resection

OBJECTIVE

Presurgical identification of patients at high risk for early recurrence of hepatocellular carcinoma (HCC) after resection could warrant additional therapies. F-fluorodeoxyglucose (FDG) uptake by the tumour on preoperative PET can predict HCC recurrence after resection as effectively as poor differentiation or presence of microvascular invasion (MVI) on postsurgical histology. A better sensitivity for the detection of HCC nodules has been reported with F-fluorocholine (FCH), a PET tracer of lipid metabolism. This pilot study aimed to compare preoperative FDG and FCH PET/CT for predicting early recurrence of unifocal HCC, occurring within 6 months after surgical resection.

METHODS

FDG and FCH tumour uptakes were assessed on preoperative PET/CT by two masked readers. On FCH PET/CT, a photopenic lesion and a hot focus were considered as indicative of malignancy. During postoperative follow-up, recurrence was searched for by regularly performing CT and MRI.

RESULTS

In 11 consecutive HCC patients, the detection rate was greater with FCH (80%) than with FDG (27%). After resection, the overall recurrence rate was 55%. Early recurrence occurred in four patients, who were the only ones with an FDG-positive and FCH-photopenic tumour, with a significant reduction in disease-free survival. On postsurgical histology, those four patients also presented with MVI and satellite nodules. Histological differentiation and capsule disruption appeared less accurate than PET/CT or MVI in predicting early recurrence.

CONCLUSION

In unifocal HCC, the FCH photopenic pattern was associated with MVI and predicted early HCC recurrence after surgical resection as accurately as did an FDG uptake. Larger studies with FCH are warranted.