Hepatocellular carcinoma: correlation between vascular endothelial growth factor level and degree of enhancement by multiphase contrast-enhanced computed tomography

Arterial blood supply of hepatocellular carcinoma is associated with efficacy of sorafenib therapy

BACKGROUND

To explore the efficacy of sorafenib in treating hepatocellular carcinoma (HCC) and its relationship with the computed tomography (CT) and magnetic resonance imaging (MRI) features of HCC, analyze the prognostic factors of HCC patients treated with sorafenib, and investigate the relationship between imaging findings and outcomes.

METHODS

A total of 38 HCC patients who were treated with sorafenib from April 2009 to December 2010 were included in this study. HCCs were classified as good arterial supply and poor arterial supply according to the intensity enhancement on CT scan or MRI. Clinical data were collected and the survival time was calculated by Kaplan-Meier method.

RESULTS

Among these 38 patients [35 (92.1%) were males] treated with sorafenib, the median age was (53.3±11.1) years. Tumors in 17 patients had good arterial supply while those in the remained 21 patients had poor arterial supply. The median survival time (MST) was 10.7 months (95% CI, 8.7-12.7) and the 1-year overall survival (OS) was 41.0%. The MST and 1-year OS in patients with tumors with good arterial supply were 12 months (range, 4-20 months) and 52.9%, respectively, compared with those of 7 months (range, 1-16 months) and 23.8% in patients with tumors with poor arterial supply (P=0.002). Patients with BCLC stage B tumors had longer MST and higher OS than those with BCLC stage C tumors, although the differences were not statistically significant. Multivariate analysis showed that arterial supply of tumors remained statistically predictive for OS (HR =0.22; 95% CI, 0.07-0.67; P=0.008).

CONCLUSIONS

Arterial blood supply is an independent predictor for survival in HCC patients treated with sorafenib, and patients with tumors with good arterial supply benefit more than those with tumors with poor arterial supply.

Apparent diffusion coefficient value of diffusion-weighted imaging for hepatocellular carcinoma: correlation with the histologic differentiation and the expression of vascular endothelial growth factor

Objective

To evaluate whether the histopathological differentiation and the expression of vascular endothelial growth factor (VEGF) of hepatocellular carcinoma (HCC) do show correlation with the apparent diffusion coefficient (ADC) value on diffusion-weighted imaging (DWI).

Materials and Methods

Twenty-seven HCCs from 27 patients who had undergone preoperative liver MRI (1.5T) and surgical resection were retrospectively reviewed. DWI was obtained with a single-shot, echo-planar imaging sequence in the axial plane (b values: 0 and 1,000 sec/mm²). On DWIs, the ADC value of the HCCs was measured by one radiologist, who was kept 'blinded' to the histological findings. Histopathologically, the differentiation was classified into well (n = 9), moderate (n = 9) and poor (n = 9). The expression of VEGF was semiquantitatively graded as grade 0 (n = 8), grade 1 (n = 9) and grade 2 (n = 10). We analyzed whether the histopathological differentiation and the expression of VEGF of the HCC showed correlation with the ADC value on DWI.

Results

The mean ADC value of the poorly-differentiated HCCs (0.9 ± 0.13×10^-3 mm²/s) was lower than those of the well-differentiated HCCs (1.2 ± 0.22×10^-3 mm²/s) (p = 0.031) and moderately-differentiated HCCs (1.1 ± 0.01×10^-3 mm²/s) (p = 0.013). There was a significant correlation between the differentiation and the ADC value of the HCCs (r = -0.51, p = 0.012). The mean ADC of the HCCs with a VEGF expression grade of 0, 1 and 2 was 1.1 ± 0.17, 1.1 ± 0.21 and 1.1 ± 0.18×10^-3 mm²/s, respectively. The VEGF expression did not show correlation with the ADC value of the HCCs (r = 0.07, p = 0.74).

Conclusion

The histopathological differentiation of HCC shows inverse correlation with the ADC value. Therefore, DWI with ADC measurement may be a valuable tool for noninvasively predicting the differentiation of HCC.

Efficacy of antivascular photodynamic therapy using benzoporphyrin derivative monoacid ring A (BPD-MA) in 14 dogs with oral and nasal tumors

Antivascular photodynamic therapy (PDT) suppresses tumor growth and prolonged the survival in solid tumor-bearing mice. The purpose of this study was to assess the efficacy of antivascular PDT using BPD-MA for treatment of oral and nasal tumors in 14 dogs. At 15 min after initiating intravenous infusion of 0.5 mg/kg benzoporphyrin derivative monoacid ring A, tumors were irradiated with laser light at 690 nm emitted by a diode laser. The 1-year survival rate of 7 dogs with oral tumors was 71%. The 1-year survival rate of 7 dogs with nasal tumors was 57%. Imaging of each tumor was performed by using angiographic computed tomography before and after each antivascular PDT. Contrast-enhanced tumors were observed before antivascular PDT, but these tumors were not enhanced with contrast medium following antivascular PDT. Antivascular PDT is suggested to be a promising method for dogs with oral and nasal tumors that cannot be effectively treated with current antitumor therapies.

Impact of different anticancer regimens on biomarkers of angiogenesis in patients with advanced hepatocellular cancer

OBJECTIVE

Advanced hepatocellular cancer (HCC) is a highly vascularised tumor with limited treatment options. We wanted to evaluate the impact of different treatments on systemic biomarkers linked to angiogenesis.

METHODS

Two subsequent prospective, randomised, phase-I/II trials in patients with advanced HCC were performed. A total of 38 patients was randomised to a total of 4 regimens consisting of 3 cycles of 4 weeks each: Trial 1 included group 1 receiving octreotide 30 mg im on day 1, and group 2 octreotide 30 mg on day 1 plus Imatinib 400 mg po daily; Trial 2 included group 3 with oxaliplatin on day 1 (60 mg-90 mg/m(2)), and group 4 with oxaliplatin on day 1, 8, 15 (20 mg-30 mg/m(2)) in combination with octreotide 30 mg on day 1 plus imatinib 400 mg po daily. Primary outcome measure was the relative changes in plasma biomarkers over time.

RESULTS

Time-to-progression and overall survival was not different between the the two study trials. Within group 1-4, the mean relative increase from baseline to week 12 of treatment was 17, 18, 37, and 2% for s-E-selectin; -1, 90, 10, and -9% for VEGF-A; 18, 84, 141, and 74% for PDGF-BB, and 111, 142, 30, and 7% for serum AFP, respectively.

CONCLUSIONS

The increase of plasma levels for s-E-selectin and PDGF-BB seen in patients receiving chemotherapy alone may reflect activation of angiogenesis. In contrast, low-dose metronomic chemotherapy in combination with anti-angiogenic drugs seems to correlate with the least increase in biomarkers. Imatinib-octreotide temporarily leads to a decrease in PDGF-BB, whereas octreotide alone had no effect on PDGF-BB plasma levels.

Multiphase contrast-enhanced CT imaging in hepatocellular carcinoma correlation with immunohistochemical angiogenic activities

RATIONALE AND OBJECTIVES

To evaluate the correlation between enhancement parameters of multiphase contrast-enhanced computed tomography (CT) and immunohistochemical activities of vascular endothelial growth factor (VEGF), VEGF receptors, and CD34 in hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

Twenty-seven patients underwent curative resection for HCC with no preoperative treatment. We defined several CT enhancement parameters by measuring attenuation values of tumor, liver parenchyma, and aorta. The stored tissue blocks were assayed for immunohistochemical activities of VEGF, two VEGF receptors (Flt-1, Flk-1), and CD34, which were correlated with the enhancement parameters of multiphase contrast-enhanced CT.

RESULTS

The VEGF activities in HCC showed moderate positive correlation with phase difference in portal phase, delayed enhancement (DE), tumor-blood ratio, blood pool index, and tumor-parenchyma ratio in arterial phase. The Flk-1 activities in HCC showed moderate positive correlation only with DE. CD34 activity in HCC showed positive correlation with most of the CT parameters except for DE.

CONCLUSION

Our study showed that several CT enhancement parameters representing mainly delayed enhancement features were well correlated with VEGF activity in HCC, and might be valuable indicators for assessing angiogenic activity in HCC.

Poorly versus moderately differentiated hepatocellular carcinoma: vascularity assessment by computed tomographic hepatic angiography in correlation with histologically counted number of unpaired arteries

PURPOSE

To determine the vascularity of moderately and poorly differentiated hepatocellular carcinoma (mHCC and pHCC, respectively) as observed on and depicted by computed tomography during hepatic angiography and to perform pathological correlation.

MATERIALS AND METHODS

Eighty-seven consecutive patients with 89 hepatocellular carcinomas (61 mHCCs and 28 pHCCs) were surgically resected in our hospital. The degree of contrast enhancement on computed tomography during hepatic angiography of the tumors was classified into high attenuation (H), isoattenuation (I), and low attenuation (L). We also examined hepatocellular carcinomas measuring less than 4 cm in diameter. Pathologically, the number of unpaired arteries in the tumors was determined (x200 magnification).

RESULTS

The number of mHCC and pHCC in each degree of enhancement (H/I/L) was 59:1:1 and 19:6:3, respectively. The number of mHCC and pHCC measuring less than 4 cm without portal invasion was 48 and 15, respectively; the number of these tumors in each degree of enhancement (H/I/L) was 47:1:0 and 11:3:1, respectively. The mean number of unpaired arteries was 8.9 +/- 4.4 in mHCC and 5.2 +/- 4.3 in pHCC, respectively. All results were statistically significant (P < 0.01).

CONCLUSIONS

Our results indicated that the arterial blood supply of pHCC was lower than that of mHCC.

Image-Guided Biopsy-Diagnosed Renal Cell Carcinoma: Critical Appraisal of Technique and Long-Term Follow-Up

OBJECTIVES

To critically appraise and determine the impact of image-guided biopsy on the management of indeterminate renal masses. A comparison of long-term follow-up of renal cell carcinoma (RCC) diagnosed by image-guided biopsy and radiologically obvious RCC was also carried out.

PATIENTS AND METHODS

Data were collected for all the consecutive patients requiring renal core biopsies for the diagnosis of indeterminate renal masses between January 1996 and January 2006. The long-term outcome of diagnostic and nondiagnostic renal biopsies was assessed. Furthermore, the long-term outcome of RCC diagnosed following biopsies was compared with nonbiopsy radical nephrectomy done during the same time period.

RESULTS

Of the 70 biopsy procedures performed, 9 were nondiagnostic and 61 were diagnostic on histopathologic examinations (17 benign and 44 malignant). The histopathology of all radical nephrectomies was identical to the pathology of biopsy specimens. Of the nine nondiagnostic cases, one patient had a repeat biopsy that was confirmed as RCC. Six patients including the case diagnosed to have RCC on repeat biopsy underwent radical nephrectomy in the nondiagnostic group. The histopathology revealed RCC in four, and angiomyelolipoma and pyelonephritis in one each. The remaining three nondiagnostic cases are under follow-up; there has been no change in the size of the lesions in a mean follow-up of 32 mo (range: 12-52). There has been no change in the size of benign lesions at a mean follow-up of 29 mo (range: 3-72). The procedure-related complication in the form of bleeding following biopsy was observed in one patient, which settled conservatively. There was no statistically significant difference (chi-square=1.134 and p value equal to 0.379) in the recurrence rate and metastases between the biopsy radical nephrectomy and nonbiopsy radical nephrectomy groups for the same stage of disease during the same period.

CONCLUSIONS

Image-guided biopsy is safe and accurately characterises indeterminate renal masses. A repeat biopsy protocol is useful in case of a nondiagnostic first biopsy. The long-term outcome following radical nephrectomy of biopsy-diagnosed RCC does not differ from the radiologically obvious RCC.

Expression of vascular endothelial growth factor in hepatocellular carcinoma and the surrounding liver: correlation with MR imaging and angiographically assisted CT

We summarize and discuss our previous research results on the correlation between findings on magnetic resonance (MR) imaging and angiographically assisted computed tomography (CT) and the intensity of vascular endothelial growth factor (VEGF) expression in hepatocellular carcinoma (HCC) and in the surrounding nontumorous liver. MR images (n = 22), CT during arterial portography (n = 20), and CT hepatic arteriography (n = 17) were retrospectively correlated quantitatively and qualitatively with VEGF expression in HCCs and in the surrounding liver assessed by western blotting. HCC-to-liver contrast-to-noise ratio correlated with VEGF expression index (VEGF(IND)) values of HCCs inversely on opposed-phase, T1-weighted, spoiled gradient recalled-echo (GRE) images, directly on T2-weighted, fast spin-echo images, and marginally and inversely on gadolinium-enhanced hepatic arterial-phase GRE images. On T2-weighted fast spin-echo images, standard deviation ratio of HCCs correlated directly with VEGF(IND) values of HCCs. By CT hepatic arteriography, the contrast-enhancement index of HCCs showed a moderate inverse correlation with VEGF(IND) values of HCCs, and the contrast-enhancement index of the liver showed marginal, moderate direct correlation with VEGF(IND) values in the liver. Heterogeneities of HCCs on images correlated directly with VEGF(IND) values of HCCs on opposed-phase T1-weighted GRE images, T2-weighted fast spin-echo images, hepatic arterial-phase GRE images, equilibrium-phase GRE images, and CT hepatic arteriogram. Our results may reflect that MR signal intensity, hepatic arterial vascularity, and heterogeneity of HCCs on CT or MR images are closely related to the intensity of VEGF expression in HCC as upregulated by hyper- or hypoxia in HCCs. Although the real effects of our results on radiologic practice are debatable at this moment, we believe that our results may help future radiologic practice in conjunction with biomolecular or genetic treatment for HCCs.

Impact of biomarkers on disease survival and progression in patients treated with octreotide for advanced hepatocellular carcinoma

BACKGROUND

Current determination of prognosis for advanced hepatocellular carcinoma (HCC) is mainly based on clinical assessment. We aimed to determine the impact of biomarkers as predictive factors for HCC progression and survival during octreotide-based treatments.

PATIENTS AND METHODS

We included patients who had been prospectively randomised to receive either octreotide (30 mg) alone monthly (n = 39) or in combination with rofecoxib (up to 50 mg bid daily, n = 32) for a minimum of 6 months, or until death occurred.

RESULTS

Overall median survival (154 days) and median time to progression (94 days) were not different for both treatments and the biomarkers investigated (VEGF-A, IGF-1, PGE-2, ET-A) were similarly distributed amongst treatment groups. Combined univariate group analysis revealed that survival was decreased for an uptake ratio of > 2 on initial octreoscan (P = 0.05); baseline serum VEGF-A and IGF-1 were further significantly associated with survival. On multivariate analysis, uncorrected serum VEGF-A appeared to be the most significant predictor for tumor progression and survival.

CONCLUSIONS

Biomarkers, in addition to established tumor markers, are independent predictors of tumor progression and survival in patients with advanced HCC treated with octreotide. Furthermore, the involvement of VEGF-A implies the inhibition of angiogenesis as a potential mechanism of action for this drug.

Construction and clinical significance of a predictive system for prognosis of hepatocellular carcinoma

AIM: The aims of this study were to explore individualized treatment method for hepatocellular carcinoma (HCC) patients whose maximum tumor size was less than 5 cm to improve prognosis and survival quality.

METHODS: Thirty cases of primary HCC patients undergoing tumor resection were retrospectively analyzed (resection group). All the tumors were proved as primary HCC with pathologic examination. The patients were divided into two groups according to follow-up results: group A, with tumor recurrence within 1 year after resection; group B, without tumor recurrence within 1 year. Immunohist-ochemical stainings were performed using 11 kinds of monoclonal antibodies (AFP, c-erbB2, c-met, c-myc, HBsAg, HCV, Ki-67, MMP-2, nm23-H1, P53, and VEGF), and expressing intensities were quantitatively analyzed. Regression equation using factors affecting prognosis of HCC was constructed with binary logistic method. HCC patients undergoing percutaneous microwave coagulation therapy (PMCT) were also retrospectively analyzed (PMCT group). Immunohistochemical stainings of tumor biopsy samples were performed with molecules related to HCC prognosis, staining intensities were quantitatively analyzed, coincidence rate of prediction was calculated.

RESULTS: In resection group, the expressing intensities of c-myc, Ki-67, MMP-2 and VEGF in cancer tissue in group A were significantly higher than those in group B (t = 2.97, P = 0.01; t = 2.42, P = 0.03<0.05; t = 2.57, P = 0.02<0.05; t = 3.43, P = 0.004<0.01, respectively); the expressing intensities of 11 kinds of detected molecules in para-cancer tissue in groups A and B were not significantly different (P>0.05). The regression equation predicting prognosis of HCC is as follows: P(1) = 1/[1+e^{-(3.663-0.412mycc-2.187Ki-67c-0.397vegfc)}]. It demonstrates that prognosis of HCC in resection group was related with c-myc, Ki-67 and VEGF expressing intensity in cancer tissue. In PMCT group, the expressing intensities of c-myc, Ki-67 and VEGF in cancer tissue in group A were significantly higher than those in group B (t = 4.57, P = 0.000<0.01; t = 2.08, P = 0.04<0.05; t = 2.38, P = 0.02<0.05, respectively); the expressing intensities of c-myc, Ki-67 and VEGF in para-cancer tissue in groups A and B were not significantly different (P>0.05). The coincidence rate of patients undergoing PMCT in group A was 88.00% (22/25), in group B 68.75% (11/16), the total coincidence rate was 80.49% (33/41).

CONCLUSION: The regression equation is accurate and feasible and could be used for predicting prognosis of HCC, it helps to select treatment method (resection or PMCT) for HCC patients to realize individualized treatment to improve prognosis.

Expression of vascular endothelial growth factor in hepatocellular carcinoma and the surrounding liver and correlation with MRI findings

OBJECTIVE

The purpose of our study was to assess the correlation between the quantitative and qualitative imaging findings on unenhanced and gadolinium-enhanced MR images and the intensity of vascular endothelial growth factor (VEGF) expression in hepatocellular carcinomas and in the surrounding nontumorous liver.

MATERIALS AND METHODS

The intensities of VEGF expression in hepatocellular carcinoma and in the surrounding liver by Western blot analysis were converted to VEGF expression indexes (VEGF(IND)) in 22 surgical specimens ranging in size from 14 to 126 mm (mean, 47.6 +/- 29.5 mm) that were resected in 22 patients (17 men and five women; age range, 41-85 years [mean, 64 years]) between April 2000 and October 2002. MR images were retrospectively evaluated to determine contrast-to-noise ratios (CNRs), signal intensity SD ratios, and phase-shift indexes. Signal intensity characteristics of hepatocellular carcinomas were reviewed independently by two experienced radiologists who were unaware of the pathologic diagnosis or the results of immunoblotting. CNRs, SD ratios, and phase-shift indexes were correlated with VEGF(IND) using a simple regression test, and signal intensity characteristics were correlated with VEGF(IND) using the Spearman's rank correlation test.

RESULTS

On opposed-phase T1-weighted spoiled gradient-recalled echo (GRE) images, CNRs correlated inversely with the VEGF(IND) of hepatocellular carcinomas (r = -0.46, p = 0.038). CNRs on T2-weighted fast spin-echo images correlated directly with the VEGF(IND) of hepatocellular carcinomas (r = 0.49, p = 0.025), and on gadolinium-enhanced hepatic arterial phase GRE images marginally and inversely correlated with VEGF(IND) (r = -0.39, p = 0.081). On T2-weighted fast spin-echo images, SD ratios correlated directly with the VEGF(IND) of hepatocellular carcinomas (r = 0.44, p = 0.044). No correlation was found between phase-shift indexes and VEGF expression. The qualitatively assessed signal intensity heterogeneities of hepatocellular carcinomas correlated directly with the VEGF(IND) of hepatocellular carcinomas on opposed-phase T1-weighted GRE, T2-weighted fast spin-echo, hepatic arterial phase GRE, and equilibrium phase GRE images.

CONCLUSION

Our results indicate that the signal intensity and heterogeneity of hepatocellular carcinomas on MR images correlate with the degree of VEGF expression in hepatocellular carcinomas.

Expression of vascular endothelial growth factor in hepatocellular carcinoma and the surrounding liver: correlation with angiographically assisted CT

OBJECTIVE

The purpose of our study was to assess the correlation between the intensity and characteristics of contrast enhancement on angiographically assisted CT and the intensity of vascular endothelial growth factor (VEGF) expression in hepatocellular carcinoma (HCC) and in the surrounding nontumorous liver.

MATERIALS AND METHODS

The intensity of VEGF expression in HCC and in the surrounding liver was expressed as a VEGF expression index by Western blot analysis in 20 surgical specimens resected in 20 patients between March 2000 and August 2002. Findings on CT during arterial portography (n = 20) and CT hepatic arteriography (n = 17) were retrospectively evaluated to determine contrast enhancement indexes and the enhancement characteristics of HCCs and of the surrounding liver. Contrast enhancement indexes and VEGF expression indexes were correlated using a simple regression test, and enhancement characteristics and VEGF expression indexes were correlated using the Spearman's rank correlation test.

RESULTS

On CT hepatic arteriography, the contrast enhancement indexes of HCCs showed moderate inverse correlation with the VEGF expression indexes of HCCs (r = -0.57, p = 0.017) and high inverse correlation with the differences between the VEGF expression indexes of HCCs and those of livers (difference in the VEGF expression index, -0.80; p = 0.0001). The contrast enhancement index of the liver showed marginal moderate direct correlation with the VEGF expression index of the liver (0.44, p = 0.076) and high inverse correlation with the difference in the VEGF expression index (-0.71, p = 0.0013). On CT during arterial portography, the contrast enhancement indexes of HCCs showed moderate inverse correlation with the difference in the VEGF expression index (-0.51, p = 0.023). The qualitative degree of heterogeneity of hepatic artery enhancement in HCC on CT hepatic arteriography showed moderate direct correlation with the VEGF expression indexes of HCCs (0.55, p = 0.033) and high direct correlation with the difference in the VEGF expression indexes (0.73, p = 0.004).

CONCLUSION

Our results indicated that the intensity and heterogeneity of hepatic artery enhancement of HCCs on CT hepatic arteriography correlated with the degree of VEGF expression in HCCs.

Bladder transitional cell carcinoma: correlation of contrast enhancement on computed tomography with histological grade and tumour angiogenesis

AIM

To investigate the correlation between the degree of contrast enhancement of bladder cancer in the early enhanced phase of helical computed tomography (CT) and microvessel density (MVD), vascular endothelial growth factor (VEGF) and histological grade.

MATERIALS AND METHODS

Sixty-five patients with transitional cell carcinoma of the bladder were examined by incremental unenhanced CT and helical CT at 40-45 s after initiation of intravenous administration of contrast medium before surgery. The CT density in Hounsfield units of bladder carcinomas were measured in the middle of the maximum diameter section of the cancer lesions on unenhanced and enhanced CT. The degree of contrast enhancement of the tumour was determined as the absolute increase in Hounsfield units. Histological grade, VEGF and MVD were analysed for each cancer. The Pearson and Spearman correlation tests were used to determine the strength of the relationships between CT enhancement and histological grade, VEGF expression and MVD.

RESULTS

Different degrees of enhancement were observed in 91 cancers during the early enhanced phase of helical CT. Mean MVDs and mean CT enhancing values of different histological grade groups were statistically different (p < 0.001). A positive correlation was found in the CT-enhancing value of bladder cancer and MVD (Pearson correlation test; r = 0.938, p < 0.001) and histological grade (Spearman rank correlation; r = 0.734, p < 0.001). VEGF of bladder cancer did not correlate with the change in CT attenuation (Spearman rank correlation; r = 0.087, p = 0.410) and MVD (Spearman rank correlation, r = 0.103, p = 0.330).

CONCLUSION

In bladder cancer, the degree of contrast enhancement during the early enhanced helical CT is correlated with the MVD and histological grade of tumour. It is possible that MVD is the histopathological basis of early contrast enhancement of bladder cancer.

Magnetic resonance imaging and expression of vascular endothelial growth factor in hepatocellular nodules in cirrhosis and hepatocellular carcinomas

We summarized and discussed our previous research results on correlation between magnetic resonance (MR) imaging findings and vascular endothelial growth factor (VEGF) expression in benign or borderline hepatocellular nodules in cirrhosis, hepatocellular carcinomas (HCCs), and in the surrounding liver. Magnetic resonance images were retrospectively correlated quantitatively and qualitatively with VEGF expression in hepatic nodules and in the surrounding liver. By immunohistochemistry, hepatic nodules with moderate to strong immunoreactivity for VEGF showed higher T1 signal intensity, and those with intense immunoreactivity for VEGF showed higher T2 signal intensity. By Western blotting, HCC-to-liver contrast-to-noise ratio correlated with VEGF indices (VEGFs) of hepatocellular carcinomas inversely on opposed-phase T1-weighted, directly on T2-weighted, and marginally and inversely on gadolinium-enhanced hepatic arterial-phase images. On T2-weighted images, standard-deviation ratio of hepatocellular carcinomas correlated directly with VEGFs of hepatocellular carcinomas. Heterogeneities of hepatocellular carcinomas on MR images correlated directly with VEGFs of HCCs on opposed-phase T1-weighted, T2-weighted, hepatic arterial-phase, and equilibrium-phase images. Our results may reflect that MR signal intensity, hepatic arterial vascularity, and heterogeneity of hepatocellular nodules on MR images are closely related to the intensity of VEGF expression as up-regulated by hyper- or hypoxia in the nodules. Gadolinium-enhanced MR imaging may be useful to monitor ischemic state of hepatocelluar nodules. Although real impacts of our results on radiologic practice have been still debatable, we believe that our results may help future radiologic practice in conjunction with biomolecular or genetic treatments for hepatocellular carcinomas.

Angiogenesis in hepatocellular nodules: Correlation of MR imaging and vascular endothelial growth factor

PURPOSE

To assess the correlation between magnetic resonance (MR) imaging findings and angiogenetic activity in hepatocellular nodules evaluated by immunohistochemical staining with antibody of vascular endothelial growth factor (VEGF).

MATERIALS AND METHODS

We searched the pathologic records of our institution from December 1999 to April 2002, and included 16 patients with hepatocellular carcinoma (N = 14), large regenerative nodule (N = 1), and dysplastic nodule (N = 1) who underwent orthotopic liver transplantation (10 patients) or partial hepatectomy (six patients) and MR imaging within an interval of two weeks. The MR images were retrospectively assessed qualitatively and quantitatively. Angiogenetic activity of the hepatic nodules was evaluated by means of immunohistochemical study for VEGF. Analysis of variance and the Scheffé criterion were used for statistical evaluation.

RESULTS

Hepatic nodules with moderate to strong immunoreactivity for VEGF showed higher signal intensity on T1-weighted images (P < 0.05) and those with intense immunoreactivity for VEGF showed higher signal intensity on T2-weighted images (P < 0.05). No correlation was found between the immunoreactivity for VEGF and tumor vascularity on postcontrast early- and late-phase images.

CONCLUSION

Our current results suggest that signal intensity on unenhanced T1- and T2-weighted MR images may correlate with immunoreactivity for VEGF. Correlation was not found between immunoreactivity for VEGF and signal intensity on gadolinium-enhanced MR images.

Single-level dynamic spiral CT of hepatocellular carcinoma: Correlation between imaging features and density of tumor microvessels

AIM: To investigate the correlation of enhancement features of hepatocellular carcinoma (HCC) revealed by single-level dynamic spiral CT scanning (DSCT) with tumor microvessel density (MVD), and to determine the validity of DSCT in assessing in vivo tumor angiogenic activity of HCC.

METHODS: Twenty six HCC patients were diagnosed histopathologically. DSCT was performed for all patients according to standard scanning protocol. Time-density curves were generated, relevant curve parameters were measured, and gross enhancement morphology was analyzed. Operation was performed to remove HCC lesions 1 to 2 weeks following CT scan. Histopathological slides were carefully prepared for the standard F₈RA immunohistochemical staining and tumor microvessel counting. Enhancement imaging features of HCC lesions were correlatively studied with tumor MVD and its intra-tumor distribution characteristics.

RESULTS: On DSCT images of HCC lesions, three patterns of time-density curve and three types of gross enhancement morphology were recognized. Histomorphologically, the distribution of positively stained tumor endothelial cells within tumor was categorized into 3 types. Curve parameters such as peak enhancement value and contrast enhancement ratio were significantly correlated with tumor tissue MVD (r = 0.508 and r = 0.423, P < 0.01 and P < 0.05 respectively). Both the pattern of time-density curve and the gross enhancement morphology of HCC lesions were also correlated with tumor MVD, and reflected the distributive features of tumor microvessels within HCC lesions. Correlation between the likelihood of intrahepatic metastasis of HCC lesions with densely enhanced pseudocapsules and rich pseudocapsular tumor MVD was found.

CONCLUSION: Enhancement imaging features of HCC lesions on DSCT scanning are correlated with tumor MVD, and reflect the intra-tumor distribution characteristics of tumor microvessels. DSCT is valuable in assessing the angiogenic activity and tumor neovascularity of HCC patients in vivo.

Clinical significance of angiogenesis in gastrointestinal cancers: a target for novel prognostic and therapeutic approaches

OBJECTIVE

To review the current data on the prognostic and therapeutic implications of tumor angiogenesis in gastrointestinal cancers.

SUMMARY BACKGROUND DATA

Numerous studies have evaluated the prognostic value of tumor angiogenesis and the potential role of antiangiogenic therapy in various gastrointestinal cancers.

METHODS

A Medline literature search was conducted using "angiogenesis" or the names of various angiogenic factors in combination with the names of gastrointestinal cancers as the key words.

RESULTS

Several studies have demonstrated a significant prognostic impact of tumor microvessel density and tumor expression of angiogenic factors, in particular vascular endothelial growth factor (VEGF), in various gastrointestinal cancers. A few studies have suggested that circulating VEGF might be a useful prognostic marker. However, results were not consistent across all studies and were limited by the retrospective nature of most studies. Antiangiogenic therapy has been shown to be effective against all common gastrointestinal cancers in preclinical studies, but currently there are few clinical data with regard to antiangiogenic therapy in gastrointestinal cancers.

CONCLUSIONS

There is mounting evidence to suggest that assessment of tumor angiogenesis might provide a novel approach of prognostication in patients with gastrointestinal cancers. However, current results from retrospective studies need to be validated by prospective studies. Antiangiogenic therapy is a promising strategy of cancer treatment that might be particularly useful in combination therapy for unresectable cancers or as an adjuvant therapy for resectable tumors.

Clinical significance of angiogenesis in gastrointestinal cancers: a target for novel prognostic and therapeutic approaches

OBJECTIVE

To review the current data on the prognostic and therapeutic implications of tumor angiogenesis in gastrointestinal cancers.

SUMMARY BACKGROUND DATA

Numerous studies have evaluated the prognostic value of tumor angiogenesis and the potential role of antiangiogenic therapy in various gastrointestinal cancers.

METHODS

A Medline literature search was conducted using "angiogenesis" or the names of various angiogenic factors in combination with the names of gastrointestinal cancers as the key words.

RESULTS

Several studies have demonstrated a significant prognostic impact of tumor microvessel density and tumor expression of angiogenic factors, in particular vascular endothelial growth factor (VEGF), in various gastrointestinal cancers. A few studies have suggested that circulating VEGF might be a useful prognostic marker. However, results were not consistent across all studies and were limited by the retrospective nature of most studies. Antiangiogenic therapy has been shown to be effective against all common gastrointestinal cancers in preclinical studies, but currently there are few clinical data with regard to antiangiogenic therapy in gastrointestinal cancers.

CONCLUSIONS

There is mounting evidence to suggest that assessment of tumor angiogenesis might provide a novel approach of prognostication in patients with gastrointestinal cancers. However, current results from retrospective studies need to be validated by prospective studies. Antiangiogenic therapy is a promising strategy of cancer treatment that might be particularly useful in combination therapy for unresectable cancers or as an adjuvant therapy for resectable tumors.