Fluorine-18 fluorodeoxyglucose positron emission tomography predicts tumor differentiation, P-glycoprotein expression, and outcome after resection in hepatocellular carcinoma

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.

(18)F-FDG-PET/CT predicts early tumor recurrence in living donor liver transplantation for hepatocellular carcinoma

The prognosis including (18)F-fluorodeoxyglucose positron emission tomography/computed tomography ((18)F-FDG-PET/CT) for the early recurrence for hepatocellular carcinoma (HCC) after living donor liver transplantation (LDLT) was not well established. Consecutive patients who underwent (18)F-FDG-PET/CT and subsequent LDLT for HCC from March 2005 to June 2011 were enrolled. The 191 patients with a median follow-up of 26.1 months were evaluated. There were 20 patients (10.5%) with early recurrence (≤6 months), 18 patients (9.4%) with late recurrence (>6 months), and 153 patients (80.1%) with no recurrence. Fifty-five patients (28.8%) displayed increased PET/CT tumor uptake. Three-year overall and disease-free survival for PET/CT-positive patients were 65.5% and 57.1%, respectively, while PET/CT-negative patients showed respective values of 89.8% and 86.8% (P = 0.001 vs. P < 0.001). Tumor variables associated with PET/CT-positive finding were preoperative AFP level, Milan, UCSF criteria, maximum tumor size, total tumor size, differentiation, vascular invasion, and serosal invasion. PET/CT-positive status was identified as an independent prognostic factor for disease-free survival influencing early recurrence in multivariable analysis (HR 3.945, 95% CI 1.196-13.016, P = 0.024). (18)F-FDG-PET/CT is an independent and significant predictor of early tumor recurrence in LDLT for HCC.

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.

Novel human monoclonal antibody against epidermal growth factor receptor as an imaging probe for hepatocellular carcinoma

OBJECTIVE

The epidermal growth factor receptor (EGFR) is overexpressed in many epithelial cancers, including hepatocellular carcinoma (HCC), and is an attractive target for cancer imaging and therapy. We attempted a novel noninvasive imaging method to evaluate anti-EGFR human monoclonal antibody clones for determining the uptake of therapeutic anti-EGFR antibody in HCC.

METHODS

In-vitro cell binding of nine I-labeled antibody clones was compared in the human epidermoid cancer cell line A431, in three HCC cell lines Hep-G2, SK-Hep1, and HuH-7, and in the EGFR-negative control cell line A4. In-labeled or I-labeled 048-006 was subjected to cell binding, competitive inhibition, and internalization assays using A431, SK-Hep1, and HuH-7. Further, In-labeled 048-006 was evaluated in in-vivo biodistribution analysis and single-photon imaging in nude tumor-bearing mice.

RESULTS

The 048-006 clone showed the highest binding to EGFR-expressing cells among the nine antibodies. In-labeled or I-labeled 048-006 specifically bound to EGFR-expressing cells with high affinity and was internalized after binding to EGFR. A431 and HuH-7 tumors showed high In-labeled 048-006 uptake, which was visualized by single-photon imaging.

CONCLUSION

Radiolabeled human anti-EGFR monoclonal antibody 048-006 has the potential to be a safer imaging probe for predicting tumor uptake of anti-EGFR antibody therapeutic agents in HCC.

Small hepatocellular carcinomas and thrombocytopenia

BACKGROUND

Clinical phenotypes of small and large hepatocellular carcinomas (HCCs) are not well characterized.

AIM

To evaluate the characteristics of small HCCs diagnosed by screening.

METHOD

A cohort of 430 small HCCs that were diagnosed through screening, were dichotomized according to a size of ≤ 3 cm or >3 cm maximum tumor diameter and compared for radiological and blood-test parameters.

RESULTS

There were 330 males and 100 females. A higher percent of females had smaller tumors. The majority of patients had single tumors, but 15% of those with larger tumors had portal vein thrombosis (PVT) compared to 5% of those with smaller tumors. Significant differences between the tumor-size groups included alpha-fetoprotein (AFP) values and platelet counts, with thrombocytopenia and elevated bilirubin levels being associated with smaller tumors. In comparing PVT-positive and PVT-negative patients, AFP levels and platelet counts were also significantly different between the 2 groups. A mean multinomial multiple logistic regression model was developed for maximum tumor diameter plus PVT.

CONCLUSIONS

The finding of larger tumors being associated with normal platelets and bilirubin levels in comparison to smaller tumors having thrombocytopenia reveals 2 different patterns of HCC presentation.

Predictive value of 18F-fluorodeoxyglucose PET/CT for transarterial chemolipiodolization of hepatocellular carcinoma

AIM: To investigate the correlation of ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography (PET) with clinical features and the prediction of treatment response.

METHODS: A total of 83 hepatocellular carcinoma (HCC) patients undergoing ¹⁸F-FDG PET before transarterial chemolipiodolization with systemic chemo-infusion between October, 2006 and May, 2009 were retrospectively enrolled. The patients included 68 men and 15 women (mean age, 60 ± 10.7 years). The effect of ¹⁸F-FDG-monitored PET uptake on clinical features and on the evaluated treatment response was ascertained with modified Response Evaluation Criteria in Solid Tumors. The PET parameters of maximal standardized uptake value of the tumor (Tsuv_max), the ratio of the tumor maximal standardized uptake value (SUV) to the liver maximal SUV (Tsuv_max/Lsuv_max) and the ratio of tumor maximal SUV to the liver mean SUV (Tsuv_max/Lsuv_mean) were tested as predictive factors.

RESULTS: Among the 3 SUV parameters, the Tsuv_max/Lsuv_mean ratio (cutoff value of 1.90) was significantly associated with tumor burden including tumor size, tumor number, α-fetoprotein levels and tumor stage (P < 0.001, P = 0.008, P = 0.011, P < 0.001, respectively). The objective response rates in patients with a high SUV ratio (≥ 1.90) were significantly better than those with a low SUV ratio (< 1.90) (P = 0.020). The overall survival rates of patients exhibiting a low Tsuv_max/Lsuv_mean ratio (< 1.90) and those with a high SUV ratio (≥ 1.90) was 38.2 and 10.3 mo, respectively (P < 0.01). However, the time to progression showed no significant difference between the groups (P = 0.15).

CONCLUSION: ¹⁸F-FDG PET can be an important predictor of HCC treatment. In particular, the Tsuv_max/Lsuv_mean ratio (cutoff value of 1.90) can provide useful information in treatment prognosis for HCC patients treated with locoregional therapy.

Phase II study of sirolimus in treatment-naive patients with advanced hepatocellular carcinoma

BACKGROUND

Rapalogs are emerging as promising targeted anticancer drugs. Activation of the PI3K/Akt/mTOR pathway has been observed in 15-50% of hepatocellular carcinomas.

METHODS

In this phase II study, patients with advanced hepatocellular carcinoma and underlying cirrhosis received sirolimus (20 mg/week for 1 month then 30 mg/week). Tumour response was assessed every 8 weeks. The primary endpoint was the objective tumour response rate according to the Response Evaluation Criteria in Solid Tumours criteria. Secondary endpoints included the objective response according to the modified Response Evaluation Criteria in Solid Tumours criteria, safety, and pharmacokinetic parameters.

RESULTS

Twenty-five patients received sirolimus for a median of 20.6 weeks. Two patients had an objective response (8%, 95CI: 0.98-26.03), including one complete response, and 8 patients had stable disease. There were 2 cases of grade 5 toxicity (infections) and 5 cases of grade 3 toxicity. The main grade 1/2 toxicity was mild transient fatigue (76%). Median time to radiological progression and overall survival were 15.3 weeks (range: 8.2-173.9) and 26.4 weeks (range: 8.2-173.9) respectively. Use of the modified Response Evaluation Criteria in Solid Tumours criteria did not identify any further responders.

CONCLUSION

These data suggest that first-line sirolimus shows antitumoural efficacy in advanced hepatocellular carcinoma. Larger trials with Child A patients are needed.

Diagnostic value for extrahepatic metastases of hepatocellular carcinoma in positron emission tomography/computed tomography scan

AIM: To evaluated the value of ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) scan in diagnosis of hepatocellular carcinoma (HCC) and extrahepatic metastases.

METHODS: A total of 138 patients with HCC who had both conventional imaging modalities and ¹⁸F-FDG PET/CT scan done between November 2006 and March 2011 were enrolled. Diagnostic value of each imaging modality for detection of extrahepatic metastases was evaluated. Clinical factors and tumor characteristics including PET imaging were analyzed as indicative factors for metastases by univariate and multivariate methods.

RESULTS: The accuracy of chest CT was significantly superior compared with the accuracy of PET imaging for detecting lung metastases. The detection rate of metastatic pulmonary nodule ≥ 1 cm was 12/13 (92.3%), when < 1 cm was 2/10 (20%) in PET imaging. The accuracy of PET imaging was significantly superior compared with the accuracy of bone scan for detecting bone metastases. In multivariate analysis, increased tumor size (≥ 5 cm) (P = 0.042) and increased average standardized uptake value (SUV) uptake (P = 0.028) were predictive factors for extrahepatic metastases. Isometabolic HCC in PET imaging was inversely correlated in multivariate analysis (P = 0.035). According to the receiver operating characteristic curve, the optimal cutoff of average SUV to predict extrahepatic metastases was 3.4.

CONCLUSION: ¹⁸F-FDG PET/CT scan is invaluable for detection of lung metastases larger than 1 cm and bone metastases. Primary HCC having larger than 5 cm and increased average SUV uptake more than 3.4 should be considered for extrahepatic metastases.

Usefulness of F-18 FDG PET/CT in the Evaluation of Early Treatment Response After Interventional Therapy for Hepatocellular Carcinoma

PURPOSE

This retrospective study investigated the usefulness of F-18 fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) after interventional therapy for hepatocellular carcinoma (HCC).

METHODS

Between March 2007 and November 2010, 31 patients (24 men, 7 women; mean age, 61.8 ± 11.0 years) with 45 lesions underwent PET/CT within 1 month after interventional therapy for HCC. Twenty-six patients with 40 lesions underwent transcatheter arterial chemoembolization (TACE), two patients with 2 lesions underwent radiofrequency ablation (RFA), and three patients with 3 lesions underwent percutaneous ethanol injection therapy (PEIT). Patients with a history of previous interventional therapy were excluded. Visual analysis was graded as positive when FDG was observed as an eccentric, nodular, or infiltrative pattern, and negative in case of isometabolic, hypometabolic, or rim-shaped uptake. For quantitative analysis, the standardized uptake value (SUV) was measured by region of interest technique. Maximum SUV (SUVmax) was assessed, and the ratio of SUVmax of tumor to mean SUV of normal liver (TNR) was calculated. The patients were divided into two groups, with and without residual tumor, based on 6-month clinical follow-up with serum alpha-fetoprotein and contrast-enhanced abdominal CT.

RESULTS

Of the 45 lesions, 24 were classified in the residual tumor group and the other 21 lesions in the no residual tumor group. No residual tumor was detected after RFA or PEIT. By visual analysis, the respective values for sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 87.5, 71.4, 77.8, 83.3, and 80.0 %. However, there were no significant differences in the SUVmax and TNR between the two groups.

CONCLUSIONS

It is suggested that FDG PET/CT may play a role in the evaluation of early treatment response after interventional therapy for HCC. The results indicate that FDG PET/CT visual analysis may be more useful than quantitative analysis. Further prospective studies with a large number of patients and established protocol are needed to substantiate our results.

Adding 11C-acetate to 18F-FDG at PET Examination Has an Incremental Value in the Diagnosis of Hepatocellular Carcinoma

OBJECTIVE

The sensitivity of FDG at PET examination of Hepatocellular Carcinoma (HCC) is restricted. In a few studies, all done in Oriental patients, PET-examination with (11)C-acetate has shown a higher accuracy than with FDG. In the current study, the uptake of (11)C-acetate has been compared with the uptake of FDG in the primary HCC in a cohort of Occidental patients.

MATERIAL AND METHODS

44 patients underwent PET-examination with both tracers with a mean of 9 days between the examinations. 26 patients had a microscopical diagnosis and 18 were diagnosed with multimodal radiological methods. At least one relevant radiological examination was available for comparison.

RESULTS

At visual evaluation, 13 of the HCC's were positive at PET-examination using FDG and 34 were positive using (11)C-acetate (p<0.001). Median tumor SUVmean of (11)C-acetate was 4.7 and of FDG was 1.9 (p<0.001). There was also a higher uptake of (11)C-acetate by the surrounding liver tissue than of FDG. Median liver SUVmean of [u]11[/u]C-acetate was 3.2 and of FDG it was 1.7 (p<0.001). This corresponded to a median tumour/liver tissue ratio for (11)C-acetate of 1.4 and for FDG of 1.0 (p<0.05). Previous reports of a negative correlation between the uptake of the tracers were weakly supported. In 4 large tumors some portions being hot using one of the tracers were cold using the other tracer and vice versa.

CONCLUSION

Adding registration with (11)C-acetate to registration with FDG at PET-examination has an incremental value in the diagnosis of HCC. A higher tumor uptake of (11)C-acetate cannot be taken full advantage of because of a higher uptake also by the surrounding liver tissue.

CONFLICT OF INTEREST

None declared.

Positron emission tomography in hepatobiliary and pancreatic malignancies: a review

BACKGROUND

The prognosis for hepatobiliary and pancreatic malignancies is dismal. Surgery remains the primary curative option, but unresectable disease is often discovered during operative exploration. Positron emission tomography (PET) provides unique biological information different from current imaging modalities. The role of PET in detecting hepatobiliary and pancreatic malignancies has not yet been established. The purpose of this article was to review the literature on the use of PET in hepatobiliary and pancreatic malignancies.

DATA SOURCES

We performed an extensive search on PubMed using PET and hepatocellular, pancreatic, gallbladder, and cholangiocarcinoma as keywords, excluding articles not written in English or on nonhuman subjects, case reports, and series with <5 patients.

CONCLUSIONS

Although PET has shown usefulness in the diagnosis of certain cancers, current literature cautions against the use of PET for determining malignant potential of primary liver and pancreatic lesions. Literature on PET more strongly supports clinical roles for restaging of hepatobiliary and pancreatic malignancies, and for identifying metastatic disease.

Patients with non-[18 F]fludeoxyglucose-avid advanced hepatocellular carcinoma on clinical staging may achieve long-term recurrence-free survival after liver transplantation

There is increasing evidence that a relevant number of patients with hepatocellular carcinoma (HCC) exceeding the Milan criteria may benefit from liver transplantation (LT). We retrospectively analyzed the prognostic significance of [(18) F]fludeoxyglucose ([(18) F]FDG) positron emission tomography (PET) for identifying appropriate LT candidates with advanced HCC on clinical staging. Between 1995 and 2008, 111 patients with HCC were listed for LT. All underwent a pretransplant PET evaluation. LT was performed for 91 of these patients. The tumor recurrence rate after LT was 3.6% for patients with non-[(18) F]FDG-avid (PET(-) ) tumors, but it was 54.3% for patients with [(18) F]FDG-avid (PET(+) ) tumors (P < 0.001). The 5-year recurrence-free survival rates were comparable for patients with tumors meeting the Milan criteria (86.2%) and patients with PET(-) HCC exceeding the Milan criteria (81%) at LT, but these rates were significantly higher than the rate for liver recipients with [(18) F]FDG-avid advanced HCC (21%, P = 0.002). In a multivariate analysis, negative PET findings (odds ratio = 21.6, P < 0.001), an alpha-fetoprotein level <400 IU/mL (odds ratio = 3.3, P = 0.013), and a total tumor diameter <10 cm (odds ratio = 3.0, P = 0.022) were identified as pretransplant prognostic variables for recurrence-free survival. A PET(+) status was assessed as the only independent clinical predictor of tumor-related patient dropout from the waiting list (hazard ratio = 5.7, P = 0.01). Patients with non-[(18) F]FDG-avid HCC beyond the Milan criteria according to clinical staging may achieve excellent long-term recurrence-free survival after LT.

Liver-specific contrast agent-enhanced magnetic resonance and ¹⁸F-fluorodeoxyglucose positron emission tomography findings of hepatocellular adenoma: report of a case

We report a case of hepatocellular adenoma, focusing on the findings of liver-specific contrast agent-enhanced magnetic resonance imaging (MRI) and ¹⁸F-fluorodeoxyglucose positron emission tomography (FDG-PET). The patient was a 37-year-old woman, referred to us after contrast-enhanced computed tomography showed a homogeneous, poorly enhanced liver tumor, 2.8 cm in diameter. Magnetic resonance imaging showed a liver mass with significant fatty change. The tumor increased in size to 3.3 cm over 9 months of follow-up. Gadolinium-ethoxybenzyl-diethylenetriamine penta-acetic acid-enhanced MRI revealed spotty enhancement in the hypointense tumor in the hepatobiliary phase. Subsequent FDG-PET showed increased uptake of FDG (maximum standardized uptake value 5.0), which suggested the possibility of malignancy. The patient underwent partial hepatectomy, and histological examination of the resected specimen revealed a tumor composed of hepatocyte-like cells with minimal cellular atypia and significant diffuse fatty change. Based on these findings, we diagnosed hepatocellular adenoma.

Metastasis of hepatocellular carcinoma to the ovary: a case report and review of the literature

Metastasis of hepatocellular carcinoma (HCC) to the ovary is notably rare. We present a case of HCC metastasis to the ovary with a review of the literature, which includes only 7 reported cases. A 43-year-old hepatitis B virus carrier was admitted with a right ovarian cystic mass. She had been diagnosed with HCC 2 years prior, for which she underwent transarterial chemoembolization followed by right posterior sectionectomy. Eight months after the hepatectomy, the first intrahepatic recurrence was detected and treated with transarterial chemoembolization. An additional intrahepatic recurrence occurred 12 months after transarterial chemoembolization and was managed with left medial sectionectomy and intra-operative radiofrequency ablation. Over the following 3 months, the patient developed elevated alpha-fetoprotein, and positron emission tomography showed a cystic mass in the right side of the pelvic cavity with focal hypermetabolic activity, which suggested a site of recurrent HCC. An exploratory laparotomy was performed, and a soft, ovoid cystic mass was identified in the right ovary. There was no evidence of metastases in the liver, left ovary, or peritoneum. Because of the absence of tumor on the surface of the ovary and the lack of peritoneal seeding, the mode of metastasis was thought to be hematogenous. Therefore, a right salphingo-oophorectomy was performed. The pathological features showed metastatic HCC with clear resection margins. Although metastasis of HCC to the ovary is very rare, it should be suspected in a female patient with a lower abdominal mass and an elevated serum AFP level in the absence of other demonstrable metastases.

The role of preoperative [18F]fluorodeoxyglucose positron emission tomography in predicting early recurrence after curative resection of hepatocellular carcinomas

PURPOSE

(18)F-fluorodeoxyglucose (FDG) uptake on positron emission tomography (PET) scan reflects tumor differentiation and predicts clinical outcome in patients with hepatocellular carcinoma (HCC). We investigated the correlation of PET scans with tumor differentiation and early tumor recurrence (time-to-recurrence <1 year).

METHODS

We reviewed the medical records of 93 patients with HCC who underwent curative resection at our hospital from August 2004 through December 2008. PET scans were performed preoperatively, and the maximum standardized uptake value of the tumor (SUV(tumor)) and the tumor-to-non-tumor SUV ratio (TNR) were calculated from FDG uptake.

RESULTS

Twenty-six (27.9%) had recurrences and 12 of them (46.2%) had early recurrences. SUV(tumor) and TNR correlated strongly with tumor differentiation (p < 0.001). Early recurrence-free and the overall survival rates in the low TNR group (TNR <2.0) were higher than in the high TNR group (TNR ≥2.0) (p = 0.015, p = 0.013). According to univariate analysis, predictors of early tumor recurrence were large tumor size (≥5 cm), high TNR (≥2), high SUV(tumor) (≥4), and high Edmoson-Steiner grade. However, on multivariate analysis, none of the examined factors were statistically significant independent predictor.

CONCLUSION

PET scans reflect tumor differentiation in HCCs. Because high TNR (TNR ≥2) and SUV(tumor) (SUV ≥4) were these cutoff point significant predictors in univariate analysis, future studies with more statistical power are needed to assess the significance.

Proliferative activity in hepatocellular carcinoma is closely correlated with glucose metabolism but not angiogenesis

BACKGROUND & AIMS

This study investigated the relationship between tumor proliferative activity and the grade of tumor glucose metabolism or angiogenesis in hepatocellular carcinoma (HCC).

METHODS

The study was performed as a retrospective analysis of 63 patients with HCC who underwent fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) as a preoperative examination prior to liver resection. Tumor proliferative activity was evaluated by the Ki-67 labeling index (LI). The grade of tumor glucose metabolism was evaluated by measuring the protein expression level of glucose transporter (GLUT)-1, expression level of pyruvate kinase type M2 (PKM2) mRNA, and FDG uptake. The grade of tumor angiogenesis was evaluated by the protein expression level of vascular endothelial growth factor (VEGF) and tumor microvessel density.

RESULTS

All patients were divided into tertiles according to the Ki-67 LI: the low LI group (n = 21), the intermediate LI group (n = 21), and the high LI group (n = 21). The high LI group showed a tendency to have advanced tumor stage, and lower disease-free survival and overall survival rates than the low LI and the intermediate LI groups. The expression grade of GLUT-1, PKM2 mRNA, and FDG uptake gradually increased with the Ki-67 LI. On the other hand, the protein expression grade of VEGF and microvessel density was paradoxically decreased with the Ki-67 LI.

CONCLUSIONS

These data suggest that (1) the proliferative activity of a resected specimen predicted the prognosis in patients with HCC; (2) the proliferative activity was closely correlated with the glucose metabolism, but not with angiogenesis.

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 (18) F-2-fluoro-2-deoxyglucose ((18) F-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 (18) F-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.

Preoperative FDG-PET predicts recurrence patterns in hepatocellular carcinoma

PURPOSE

We investigated the usefulness of preoperative fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) as a tool for predicting recurrence patterns to select patients for liver resection as an initial surgical strategy for hepatocellular carcinoma.

METHODS

Sixty-three consecutive hepatocellular carcinoma patients undergoing FDG-PET were enrolled. They were classified according to the initial recurrence patterns (beyond the Milan criteria [MC], within the MC, and no recurrence) and the time intervals before initial postoperative recurrence (within 1 year, after 1 year or later, and no recurrence). The tumor-to-nontumor ratio (TNR) obtained by FDG-PET and survival rates were compared among the groups.

RESULTS

TNR in the recurrence within the MC group (1.9 ± 1.6) and no recurrence group (1.3 ± 1.5) was significantly lower than that in the beyond the MC group (2.9 ± 2.6). TNR was an independent predictive factor of recurrence patterns in multivariate analysis. TNR in the groups with recurrence after 1 year or later (1.6 ± 0.8) and no recurrence (1.3 ± 0.5) were significantly lower than that in the within 1-year group (3.1 ± 2.7). TNR was an independent predictive factor of the interval before initial recurrence by multivariate analysis.

CONCLUSIONS

Preoperative FDG-PET predicts hepatocellular carcinoma recurrences within the MC or no recurrence and recurrences after 1 year or later. FDG-PET may be useful for selecting appropriate patients for liver resection as an initial surgical strategy.

Clinical applications of positron emission tomography in hepatic tumors

Fluorodeoxyglucose (FDG), which allows the evaluation of glucose metabolism, is widely used for tumor diagnosis using positron emission tomography (PET). FDG-PET, which is used for the diagnosis of intrahepatic tumor lesions, shows high FDG accumulation in cholangiocellular carcinoma (CCC) and metastatic liver cancer. FDG-PET shows high FDG accumulation in moderately or poorly differentiated hepatocellular carcinoma (HCC) and is useful for the diagnosis of extrahepatic HCC metastases and recurrences. However, because the imaging method frequently shows low FDG accumulation in well-differentiated HCC, it is not very useful for that diagnosis. For the diagnosis of well-differentiated HCC, F-18 fluorocholine for evaluation of phospholipid metabolism and C-11 acetate for evaluation of free fatty acid metabolism are useful in the diagnosis of that HCC. It is expected that the combination of these PET agents will enhance the diagnostic performance of FDG-PET for HCC in the future. The problem of a lack of anatomical information is being resolved with the development of the use of PET in combination with computed tomography or magnetic resonance imaging. For the problem of low resolution, PET devices using semiconductors have been developed.

Detection of distant metastasis to skeletal muscle by 18F-FDG-PET in a case of intrahepatic cholangiocarcinoma

Intrahepatic cholangiocarcinoma is a rare malignancy that originates from the epithelial cells of the intrahepatic bile ducts. Intrahepatic cholangiocarcinoma can metastasize in lymphatic chains, including the hepatoduodenal ligament, and it often invades adjacent organs or metastasizes to other visceral organs such as the lungs, bones, adrenal glands, and brain. However, distant skeletal muscle metastasis is very rare. Moreover, a metastatic skeletal muscle tumor rarely shows specific symptoms, making it difficult to identify in a routine examination. A 45-year-old man with a chief complaint of right upper quadrant abdominal pain was admitted to our hospital. Abdominal ultrasound and computed tomography with contrast enhancement showed a malignant mass in the right hepatic lobe, and 2-[¹⁸F] fluoro-2-deoxy-D-glucose positron-emission tomography revealed distant skeletal muscle metastases in the thorax and buttock. The patient underwent an ultrasound-guided percutaneous needle biopsy for the metastatic low-echo masses in the skeletal muscle.

Contribution of biomarkers and imaging in the management of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the most frequent malignant tumour of the liver. HCC prognosis is dependent on the determination of the tumour stage by conventional imaging and early screening. However, patient survival can vary with the same tumour stage. Biomarkers thus have a role in providing an earlier diagnosis, better prognosis classification before treatment and classification prognosis during treatment. In this review article, we will provide a successive, detailed description of the serum, pathological, molecular and imaging markers of HCC.

FDG PET for giant cavernous hemangioma: important clue to differentiate from a malignant vascular tumor in the liver

Giant cavernous hemangioma of the liver sometimes has a very inhomogeneous appearance with intratumoral degeneration on computed tomography or magnetic resonance imaging, and may mimic a malignant hepatic tumor, including angiosarcoma. There are many reports about F-18 fluorodeoxyglucose (FDG) uptake of angiosarcoma; however, knowledge regarding positron emission tomography findings with FDG for giant hepatic cavernous hemangioma is still limited. We herein present 2 cases of giant hepatic cavernous hemangioma in which low FDG uptake was considered helpful to differentiate from malignant hepatic tumor.

18F-fluorodeoxyglucose uptake on positron emission tomography as a prognostic predictor in locally advanced hepatocellular carcinoma

BACKGROUND

Metabolic activity assessed by (18)F-fluorodeoxyglocuse-positron emission tomography ((18)F-FDG-PET) reflects biological aggressiveness and prognoses in various tumors. The authors present a correlation between tumor metabolic activity and clinical outcomes in patients with hepatocellular carcinoma (HCC).

METHODS

Over a 3-year period (2005-2008), 135 locally advanced HCC patients were treated with localized concurrent chemoradiotherapy (CCRT; external beam radiotherapy at 45 grays for 5 weeks plus concurrent hepatic arterial infusion of 5-fluorouracil during the first and fifth week) followed by repetitive hepatic arterial infusional chemotherapy with 5-fluorouracil and cisplatin. Among them, the authors studied 107 who received (18)F-FDG-PET before CCRT. Maximal standardized uptake values (SUVs) of tumors were calculated.

RESULTS

The median maximal tumor SUV was 6.1 (range, 2.4-∼19.2). Patients with low maximal tumor SUVs (<6.1) had a higher disease control rate than those with high maximal tumor SUVs (≥6.1) (86.8% vs 68.5%, respectively, P = .023). Both median progression-free survival (PFS; 8.4 vs 5.2 months; P = .003) and overall survival (OS; 17.9 vs 11.3 months; P = .013) were significantly longer in the low maximal tumor SUV group than in the high maximal tumor SUV group, respectively. In multivariate analysis, low maximal tumor SUV and objective responses to CCRT remained significant for PFS and OS. The high maximal tumor SUV group was more likely to have extrahepatic metastasis within 6 months than the low maximal tumor SUV group (58.1% vs 26.8%, respectively; P < .001). Similar results were obtained for the maximal tumor SUV/normal liver maximal SUV ratio (<2 vs ≥2) concerning progression, death, and extrahepatic metastasis.

CONCLUSIONS

Metabolic activity may be useful not only in predicting prognosis and treatment responses, but also in establishing optimal treatment plans in locally advanced HCC.

[Hepatocellular carcinoma and cholangiocarcinoma]

Hepatocellular carcinoma and cholangiocarcinoma are relatively rare tumors of the gastrointestinal tract in western Europe but their incidence has been increased in recent years. Newly diagnosed intrahepatic lesions or intrahepatic cholestasis require extensive laboratory tests and imaging studies in order to confirm the diagnosis of hepatocellular carcinoma, intrahepatic or extrahepatic cholangiocarcinoma. The treatment options range from liver resection or liver transplantation to conservative measures (in cases of non-resectable lesions). This review article aims to provide an overview on the diagnostic options and the subsequent treatment.

Complete Metabolic Response with Recanalization of Portal Vein Tumor Thrombosis after Sunitinib in a Patient with Advanced Hepatocellular Carcinoma

The prognosis of patients with advanced hepatocellular carcinoma (HCC) is very poor. The outcome of these patients is particularly bleak when the disease is complicated by portal vein tumor thrombosis (PVTT), since the increased portal pressure often causes serious gastrointestinal bleedings. Before the introduction of sorafenib (SOR), a tyrosine kinase inhibitor, no effective treatment was available for patients with advanced disease. SOR is now considered the standard treatment even for patients with tumor thrombosis, although the well-known interference between tyrosine kinase inhibitors and the coagulation pathway calls for caution against their use in this setting. Here, we report the case of a 74-year-old male patient with advanced HCC and PVTT treated with sunitinib (SUN), another multikinase inhibitor. During the third cycle, our patient experienced a life-threatening hematemesis with hemorrhagic shock that required intensive care treatment and SUN discontinuation. However, he completely recovered, and the PET/CT scan performed 1 year after the adverse effect demonstrated no evidence of the tumor together with portal vein recanalization. The short course of SUN causing both tumor response and gastrointestinal bleeding warrants further studies on the effectiveness of SUN in this setting as well as on the duration of treatment with multikinase inhibitors in patients with tumor thrombosis.

P-glycoprotein related drug interactions: clinical importance and a consideration of disease states

IMPORTANCE OF THE FIELD

P-glycoprotein (P-gp) is the most characterized drug transporter in terms of its clinical relevance for pharmacokinetic disposition and interaction with other medicines. Clinically significant P-gp related drug interactions appear restricted to digoxin. P-gp may act as a major barrier to current and effective drug treatment in a number of diseases including cancer, AIDS, Alzheimer's and epilepsy due to its expression in tumors, lymphocytes, cell membranes of brain capillaries and the choroid plexus.

AREAS COVERED IN THIS REVIEW

This review summarizes the current understanding of P-gp structure/function, clinical importance of P-gp related drug interactions and the modulatory role this transporter may contribute towards drug efficacy in disease states such as cancer, AIDS, Alzheimer's and epilepsy.

WHAT THE READER WILL GAIN

The reader will gain an understanding that the clinical relevance of P-gp in drug interactions is limited. In certain disease states, P-gp in barrier tissues can modulate changes in regional distribution.

TAKE HOME MESSAGE

P-gp inhibition in isolation will not result in clinically important alterations in systemic exposure; however, P-gp transport may be of significance in barrier tissues (tumors, lymphocytes, brain) resulting in attenuated efficacy.

Increased 18F-FDG uptake of hepatocellular carcinoma on positron emission tomography independently predicts tumor recurrence in liver transplant patients

The aim of this retrospective trial was to analyze the value of preoperative (18)F-fluoro-deoxyglucose positron emission tomography ((18)F-FDG PET) to predict parameters of tumor aggressiveness among liver transplant (OLT) patients with hepatocellular carcinoma (HCC). Fifty-five patients with HCC underwent (18)F-FDG-PET during evaluation for OLT. Nineteen patients demonstrated increased (18)F-FDG uptake on PET pre-OLT (PET(+)), and 36 patients revealed negative PET findings (PET(-)). PET(+) patients showed a relative risk of 9.5 and 6.4 for poor differentiation and for microvascular invasion (MVI) in the HCC at explant pathology, respectively. Of the 10 patients (18.2%) who developed HCC recurrences, 9 (90%) revealed increased (18)F-FDG uptake pre-OLT; only 1 (10%) showed a PET(-) status (P < .001). Apart from poor tumor differentiation, PET(+) status was identified as an independent predictor of tumor recurrence post-OLT (odds ratio, 23.9). Our study demonstrated that (18)F-FDG uptake on PET is a reliable preoperative predictor of tumor recurrence after OLT in patients with HCC, triggered by its high association with poor tumor differentiation and MVI.

The role of (18)F-fluorodeoxyglucose positron emission tomography in the diagnosis, staging, and follow-up of cholangiocarcinoma

(18)F-Fluorodeoxyglucose positron emission tomography ((18)FDG-PET) is a new diagnostic technique for the diagnosis and staging of cholangiocarcinoma. For diagnosis of a primary cholangiocarcinoma, (18)FDG-PET seems to be helpful to discriminate between malignant and benign lesions. However, the accuracy of (18)FDG-PET seems to be dependent on the anatomic location, growth pattern, and pathologic characteristics of the lesion. It has been proved that the accuracy of (18)FDG-PET is limited to detection of extrahepatic, infiltrating, and mucinous cholangiocarcinomas. Due to its lower sensitivity, (18)FDG-PET provides complementary rather than confirmative information in the diagnosis of regional lymph node metastasis. In contrast, it has high accuracy in detecting unsuspected distant metastases. The role of (18)FDG-PET in detecting cancer recurrence, monitoring treatment response, and predicting prognosis is still controversial.

Influence of chemoresistance and p53 status on fluoro-2-deoxy-D-glucose incorporation in cancer

Both mutant p53 and chemoresistance are poor prognostic factors in cancer. Many studies have examined the influence of these factors on fluoro-2-deoxy-D-glucose (FDG) incorporation. Whilst mutant p53 is associated with increased FDG incorporation, chemoresistance, especially when associated with P-glycoprotein, is associated with decreased FDG incorporation.

Preoperative prediction of poorly differentiated components in small-sized hepatocellular carcinoma for safe local ablation therapy

BACKGROUND

Poorly differentiated hepatocellular carcinoma (HCC) has a malignant potential such as frequent microvascular invasion even if the tumor is smaller than 3 cm in diameter. The aim of this study was to clarify the preoperative predictors of poorly differentiated HCC for safe local ablation therapy.

METHODS

Sixty-six patients underwent a hepatic resection for solitary small-sized HCC (<or=3 cm) were included in this study. According to the postoperative histological examination, the patients were divided into a "poorly differentiated group" (n = 17) and a "well/moderately differentiated group" (n = 49). This study investigated the clinicopathological factors and imaging findings, and elucidated the predictive factors of the poorly differentiated type.

RESULTS

In a univariate analysis, serum hepatitis B surface antigen positive, hepatitis C virus antibody negative, alpha-fetoprotein level, des-gamma-carboxy prothrombin level, and a high contrast-to-noise ratio (CNR) in T2-weighted MR imaging were significantly associated with the poorly differentiate type. In a multivariate analysis, a high CNR in T2-weighted MR imaging was the only independent predictor of the poorly differentiated type. In the postoperative pathological findings, portal vein invasion and intrahepatic metastasis were significantly frequent in the poorly differentiated group.

CONCLUSIONS

The CNR in T2-weighted MR imaging is a useful tool to predict poorly differentiated HCC preoperatively.

Diffuse intrahepatic recurrence after percutaneous radiofrequency ablation for solitary and small hepatocellular carcinoma

Two patients developed segmental, diffuse intrahepatic recurrence after percutaneous radiofrequency ablation (RFA) to treat a primary, solitary, and small (2.5 cm) hepatocellular carcinoma (HCC). Despite the size of the HCC, levels of the tumor markers (α-fetoprotein, α-fetoprotein-L3%, and des-γ-carboxyprothrombin) were all elevated before RFA, and tumors in both patients were contiguous with a major branch of the portal vein. Tumor biopsies of both patients revealed moderately differentiated HCC but diagnostic imaging showed an area of reduced tumor blood flow, suggesting a poorly differentiated component. Since early detection of post-RFA malignancies by standard ultrasonography and contrast-enhanced computed tomography was difficult, the most sensitive indicator of recurrence in these two patients was the elevated tumor markers. The diffuse intrahepatic recurrence was thought to be caused by increased intratumoral pressure during RFA, resulting in the dissemination of cancer cells through the contiguous portal vein. The clinical course of these tumors indicate that the choice of RFA should be carefully considered when treating specific subtype of HCC that is adjacent to main portal vein branch and involves a possible poorly differentiated component and that surgical resection or combinations of RFA with other treatment modalities such as transcatheter arterial chemoembolization should be considered as alternative treatment strategies.

18F-FDG-uptake of hepatocellular carcinoma on PET predicts microvascular tumor invasion in liver transplant patients

Vascular invasion of hepatocellular carcinoma (HCC) is a major risk factor for poor outcome after liver transplantation (LT). The aim of this retrospective analysis was to assess the value of preoperative positron emission tomography (PET) using (18)F-fluorodeoxyglucose ((18)F-FDG) in liver transplant candidates with HCC for predicting microvascular tumor invasion (MVI) and posttransplant tumor recurrence. Forty-two patients underwent LT for HCC after PET evaluation. Sixteen patients had an increased (18)F-FDG tumor uptake on preoperative PET scans (PET +), while 26 recipients revealed negative PET findings (PET-) pre-LT. PET- recipients demonstrated a significantly better 3-year recurrence-free survival (93%) than PET + patients (35%, p < 0.001). HCC recurrence rate was 50% in the PET + group, and 3.8% in the PET-population (p < 0.001). PET + status was identified as independent predictor of MVI [hazard ratio: 13.4]. Patients with advanced PET negative tumors and patients with HCC meeting the Milan criteria had a comparable 3-year-recurrence-free survival (80% vs. 94%, p = 0.6). Increased (18)F-FDG uptake on PET is predictive for MVI and tumor recurrence after LT for HCC. Its application may identify eligible liver transplant candidates with tumors beyond the Milan criteria.

A prospective evaluation of 18F-FDG and 11C-acetate PET/CT for detection of primary and metastatic hepatocellular carcinoma

Because (18)F-FDG PET has insufficient sensitivity for the detection of hepatocellular carcinoma (HCC), (11)C-acetate PET has been proposed as another technique for this use. We prospectively evaluated the value of PET/CT using these 2 tracers for the detection of primary and metastatic HCC.

METHODS

One hundred twelve patients (99 with HCC, 13 with cholangiocellular carcinoma) underwent biopsy and (18)F-FDG and (11)C-acetate PET/CT.

RESULTS

The overall sensitivities of (18)F-FDG, (11)C-acetate, and dual-tracer PET/CT in the detection of 110 lesions in 90 patients with primary HCC were 60.9%, 75.4%, and 82.7%, respectively. Elevated serum alpha-fetoprotein levels, an advanced tumor stage, portal vein tumor thrombosis, large tumors, and multiple tumors were significantly associated with positive (18)F-FDG PET/CT results. Uptake of (11)C-acetate was associated with large and multiple tumors. For (18)F-FDG, the sensitivities according to tumor size (1-2, 2-5, and >/=5 cm) were 27.2%, 47.8%, and 92.8%, respectively; for (11)C-acetate, these respective values were 31.8%, 78.2%, and 95.2%. (18)F-FDG was more sensitive in the detection of poorly differentiated HCC. Overall survival was lower in patients with (18)F-FDG PET/CT positive for all indexed lesions than in those with FDG negative or partially positive through the entire follow-up period. In analysis based on biopsied lesions, the sensitivity of (18)F-FDG PET/CT was 64.4% for primary HCC and 84.4% for (11)C-acetate PET/CT. The overall sensitivities of (18)F-FDG, (11)C-acetate, and dual-tracer PET/CT for 35 metastatic HCCs were 85.7%, 77.0%, and 85.7%, respectively. There was no significant difference in the sensitivity of tracers according to metastatic tumor size, location, or differentiation.

CONCLUSION

The addition of (11)C-acetate to (18)F-FDG PET/CT increases the overall sensitivity for the detection of primary HCC but not for the detection of extrahepatic metastases. (18)F-FDG, (11)C-acetate, and dual-tracer PET/CT have a low sensitivity for the detection of small primary HCC, but (18)F-FDG PET/CT has a relatively high sensitivity for the detection of extrahepatic metastases of HCC.

Primary Cancer of the Liver and Biliary Duct

F-18-FDG PET and PET/CT are useful for staging, predicting the prognosis, and evaluating recurrence and treatment response in hepatocellular carcinomas (HCCs) and cholangiocarcinomas. Increased F-18-FDG uptake within tumors could be a surrogate marker of aggressive behavior and poor clinical outcome, despite high false-negative rates in detecting primary intrahepatic low-grade HCCs and periductal-infiltrating cholangiocarcinomas. Dualtracer PET or PET/CT using carbon-11-acetate and F-18-FDG will increase diagnostic performance in HCC.

Positron emission tomography/computed tomography with 18F-fluorodeoxyglucose identifies tumor growth or thrombosis in the portal vein with hepatocellular carcinoma

Patients suffering from hepatocellular carcinoma (HCC) with tumor thrombus in the portal vein generally have a poor prognosis. Portal vein tumor thrombus must be distinguished from portal vein blood thrombus, and this identification plays a very important role in management of HCC. Conventional imaging modalities have limitations in discrimination of portal vein tumor thrombus. The application of positron emission tomography (PET) with ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) for discrimination between tumor extension and blood thrombus has been reported in few cases of HCC, while portal tumor thrombosis and portal vein clot identified by ¹⁸F-FDG PET/CT in HCC patients has not been reported so far. We present two HCC cases, one with portal vein tumor thrombus and one thrombosis who were identified with ¹⁸F-FDG PET/CT. This report illustrates the complimentary value of combining the morphological and functional imaging in achieving a correct diagnosis in such clinical situations.