Prediction of pathological response to preoperative chemotherapy for pancreatic ductal adenocarcinoma using 2-[18F]-fluoro-2-deoxy-d-glucose positron-emission tomography

AIM

To determine whether the pathological response to preoperative chemotherapy for pancreatic ductal adenocarcinoma (PDAC) can be predicted using 2-[18F]-fluoro-2-deoxy-d-glucose positron-emission tomography (F-18 FDG-PET).

MATERIALS AND METHODS

Twenty-eight patients with PDAC who underwent only neoadjuvant chemotherapy (NAC) before surgery were enrolled in the study. All patients had F-18 FDG-PET examinations before NAC. The resected specimen was pathologically evaluated according to the Classification of Pancreatic Carcinoma (7th edn). Patients were categorised into a non-response group and a response group based on the pathological findings. The non-response group (Grades 1a and 1b) showed ≤50% necrosis in the specimen, while the specimens of the response group (Grades 2-3) showed >50% necrosis. The maximum standardised uptake values (SUVmax) of the tumours on F-18 FDG-PET were measured. The mean values of SUVmax were compared between the two groups. The diagnostic performance of SUVmax in distinguishing the two groups was also evaluated using receiver operating characteristic analysis.

RESULTS

The mean SUVmax of the response group was higher than that of the non-response group (9.00 ± 1.78 versus 4.26 ± 2.35; p<0.001). The optimal cut-off value of SUVmax was 9.28 for distinguishing the two groups. The sensitivity, specificity, and accuracy for the prediction in the response group were 80%, 95.7%, and 92.9%, respectively.

CONCLUSIONS

SUVmax on F-18 FDG-PET may be useful as a biomarker to predict the pathological response to NAC in patients with PDAC.

Predictors of therapeutic effect of transarterial chemoembolisation using drug-eluting beads for hepatocellular carcinoma

AIMS

To identify predictors of a therapeutic effect after transarterial chemoembolisation using drug-eluting beads (DEB-TACE) for hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

Between January 2015 and July 2015, tumour variables and angiographic data were collected for 25 patients (49 target lesions) after they had undergone the DEB-TACE procedure for HCC. The therapeutic effect was evaluated according to the Response Evaluation Criteria in Cancer of the Liver at follow-up dynamic computed tomography (CT) performed within 1-4 months after the procedure. A p<0.05 was considered significant.

RESULTS

On a target lesion basis, the objective response (TE3/4) rate was 63.3% (31 of 49). On univariate analysis, larger size (≥2 cm) was a predictor of an objective response (p=0.029). The tumour location of the medial (segment 4) or caudate (segment 1) lobe also indicated a poor therapeutic effect (TE1/2), but not at the level of significance (p=0.051). Multivariate analysis identified tumour size (odds ratio, 8.60; 95% confidence interval, 1.87-62.8) and tumour location (odds ratio, 12.2; 95% confidence interval, 2.12-129.8) as significant factors associated with a therapeutic effect. On a patient basis, 10 of 25 (40%) patients showed complete response/partial response. There were no significant differences between complete response/partial response and stable disease/progressive disease regarding age, gender, tumour markers, history of previous treatment, Child-Pugh class, T-stage, or Barcelona Clinic Liver Cancer Staging.

CONCLUSION

A short-term therapeutic effect was associated with tumour size and location on a target lesion basis.

Fatty change in moderately and poorly differentiated hepatocellular carcinoma on MRI: a possible mechanism related to decreased arterial flow

AIM

To clarify the frequency of fatty change in moderately and poorly differentiated hepatocellular carcinomas (mHCCs and pHCCs) and its relationship to arterial blood flow.

MATERIALS AND METHODS

One hundred and thirty-six surgically resected HCC lesions were studied. All patients had undergone dynamic magnetic resonance imaging (MRI) with chemical-shift-encoded water-fat imaging (CSI). The presence of fat was identified by a signal drop-off on CSI and confirmed at pathology. Lesions were classified into four groups in the arterial phase; G1, hypointense; G2, isointense; G3, slightly and heterogeneously hyperintense; G4, markedly and homogeneously hyperintense. The number of cumulative arteries (CAs) in the tumours in the pathology examination were counted.

RESULTS

A fat component was observed significantly more frequently in the pHCCs (13/21; 61.9%) compared to the mHCCs (32/101; 31.7%; p=0.013). The numbers of lesions in each group were as follows: (G1, G2, G3, G4) = (18, 9, 23, 4) in the HCCs with fat; (1, 6, 24, 51) in the HCCs without fat (p<0.001); (5, 5, 18, 4) in the mHCCs with fat; (0, 3, 19, 47) in the mHCCs without fat (p<0.001); (11, 0, 2, 0) in the pHCCs with fat; (0, 2, 3, 3) in the pHCCs without fat (p=0.001). The number of CAs in the fat-containing HCCs (5.5±2.9) was significantly lower than that in the HCCs without fat (10.8±5.3; p<0.001).

CONCLUSION

A fat component was more commonly observed in the pHCCs than in the mHCCs. The present results showed a possible mechanism of fatty change in mHCCs and pHCCs in relation to decreased arterial blood supply.

Functional assessment of the liver with gadolinium-ethoxybenzyl-diethylenetriamine penta-acetate-enhanced MRI in living-donor liver transplantation

BACKGROUND

A precise estimation of the capacity of the remnant liver following partial liver resection is important. In this study, the regional function of the liver in patients undergoing living-donor liver transplantation was evaluated by gadolinium-ethoxybenzyl-diethylenetriamine penta-acetic acid (EOB)-enhanced MRI, with special reference to the congested region.

METHODS

EOB-MRI analysis was performed before hepatectomy in donors, and 7 days after surgery in the donor and recipient. In the hepatocyte phase, from images obtained 15 min after Primovist® injection, the signal intensity in each liver segment was measured and divided by the signal intensity of the erector spinae muscle (liver to muscle ratio, LMR) for standardization. Inter-regional differences in LMRs were analysed in donors and recipients.

RESULTS

Thirty-two living donors and 31 recipients undergoing living-donor liver transplantation were enrolled. In donors, the LMRs of the remnant left lobe were almost equivalent among the liver segments. In the remnant right lobe without the middle hepatic vein, the mean(s.d.) LMR for congested segments (S5 and S8) was significantly lower than that for non-congested segments (S6 and S7): 2·60(0·52) versus 3·64(0·56) respectively (P < 0·001). After surgery, values in the non-congested region were almost identical to those in the preoperative donor liver. LMR values in the left and right lobe graft were significantly lower than those in the corresponding segment before donor surgery (P < 0·001).

CONCLUSION

The function of the congested region secondary to outflow obstruction in the remnant donor liver was approximately 70 per cent of that in the non-congested region. EOB-MRI is a promising tool to assess regional liver function, with good spatial resolution.

Correlation between portal vein anatomy and bile duct variation in 407 living liver donors

Our aim was to determine whether variant bile duct (BD) anatomy is associated with portal vein (PV) and/or hepatic artery (HA) anatomy. We examined the associations between BD anatomy and PV and/or HA anatomy in 407 living donor transplantation donors. We also examined whether the right posterior BD (RPBD) course was associated with the PV and/or HA anatomy. Variant PV, HA and BD anatomies were found in 11%, 25% and 25%, respectively, of 407 donors enrolled in this study. The presence of a variant BD was more frequently associated with a variant PV than with a normal PV (61% vs. 20%, p < 0.0001). By contrast, the presence of a variant HA was not associated with a variant BD. A supraportal RPBD was found in 357 donors (88%) and an infraportal RPBD was found in 50 donors (12%). An infraportal RPBD was significantly more common in donors with a variant PV than in donors with a normal PV (30% vs. 10%, p = 0.0004). Variant PV, but not variant HA, anatomies were frequently associated with variant BD anatomy. Additionally, an infraportal RPBD was more common in donors with a variant PV than in donors with a normal PV.

Sarcopenia as a predictor of prognosis in patients following hepatectomy for hepatocellular carcinoma

BACKGROUND

Sarcopenia was identified recently as a poor prognostic factor in patients with cancer. The present study investigated the effect of sarcopenia on short- and long-term outcomes following partial hepatectomy for hepatocellular carcinoma (HCC), and aimed to identify prognostic factors.

METHODS

Data were collected retrospectively for all consecutive patients who underwent hepatectomy for HCC with curative intent between January 2004 and December 2009. Patients were assigned to one of two groups according to the presence or absence of sarcopenia, assessed by computed tomographic measurement of muscle mass at the level of the third lumbar vertebra. Clinicopathological, surgical outcome and long-term survival data were analysed.

RESULTS

Sarcopenia was present in 75 (40·3 per cent) of 186 patients, and was significantly correlated with female sex, lower body mass index and liver dysfunction, as indicated by abnormal serum albumin levels and indocyanine green retention test at 15 min values. In patients with, and without sarcopenia, the 5-year overall survival rate was 71 and 83·7 per cent respectively, and the 5-year recurrence-free survival rate was 13 and 33·2 per cent respectively. Multivariable analysis revealed that reduced skeletal muscle mass was predictive of an unfavourable prognosis.

CONCLUSION

Sarcopenia was predictive of worse overall survival even when adjusted for other known predictors in patients with HCC after partial hepatectomy.

Prostate cancer detection: the value of performing an MRI before a biopsy

BACKGROUND

In recent years, prostate-specific antigen (PSA) screening has been widely performed. As a result, patients who need to undergo a complete physical examination for an elevated PSA level have been rapidly increasing. Magnetic resonance imaging (MRI) examination has previously been reported to be effective for the detection of prostate cancer.

PURPOSE

To evaluate the detectability of prostate cancer by performing MRI before biopsy, and to evaluate the relationship between detectability with MRI and cancer location, Gleason score (GS), and tumor size.

MATERIAL AND METHODS

MRI was performed at 1.5 Tesla in 122 consecutive patients before biopsy. The detectability of prostate cancer, including sensitivity and positive predictive value (PPV) of transrectal ultrasonography (TRUS), T2-weighted imaging (T2WI), diffusion-weighted imaging (DWI) (b=2000 s/mm(2)), apparent diffusion coefficient (ADC) map, and biopsy, was calculated using whole-mount section histopathology as a gold standard. In addition, the relationship between the detectability on each MRI sequence and factors such as cancer location (peripheral zone vs. transition zone), GS 5-10, short-axis diameter (< or =4 mm, 5-9 mm, > or =10 mm), and long-axis diameter (< or =9 mm, 10-19 mm, > or =20 mm) were also evaluated.

RESULTS

The sensitivities of TRUS, T2WI, DWI, ADC map, and biopsy were 26.9%, 41.2%, 56.7%, 57.7%, and 75.1%, respectively, and the PPVs of those modalities were 73.0%, 83.0%, 86.4%, 87.2%, and 91.5%, respectively. There was no correlation between the sensitivity of each MRI sequence and cancer location. The sensitivity of each MRI sequence increased as GS and short- and long-axis diameters of cancer lesions increased.

CONCLUSION

MRI before a biopsy has a high detectability of prostate cancer, particularly with tumor size of more than 5 mm in short-axis diameter or 10 mm in long-axis diameter.

Hepatic falciform ligament artery in patients with chronic liver diseases: detection on computed tomography hepatic arteriography

BACKGROUND

The detection rate of hepatic falciform ligament artery (FLA) has been reported as ranging from 2-25%. The rate of FLA on laparotomy, however, is reported to be higher, at 68%.

PURPOSE

To compare the detection rate of FLA on computed tomography hepatic arteriography (CTHA) with that on angiography and dynamic CT, and to clarify the clinical significance of FLA in patients with chronic liver disease.

MATERIAL AND METHODS

126 consecutive patients underwent CTHA angiography and dynamic CT to evaluate suspected liver tumors. Liver function was classified as follows: normal, n=5; Child-Pugh class A, n=94; B, n=21; and C, n=6. All CT images were obtained using multidetector (MDCT) scanners (Aquilion; Toshiba, Tokyo, Japan). For CTHA, CT images were obtained during contrast material injection through the left hepatic, proper, or common hepatic artery. On CT, FLAs were retrospectively identified within the hepatic falciform ligament and the hepatic round ligament by the paging method on a workstation (TWS-5000; Toshiba, Tokyo, Japan). The detection rates were compared among the three modalities (hepatic arterial phase of dynamic CT, CTHA, and angiography). The calibers of FLA were also correlated with the hepatic function of the patients.

RESULTS

The detection rates of FLA by angiography, dynamic CT, and CTHA were 37% (47/126), 10% (13/126), and 77% (97/126), respectively. The calibers of FLA increased as the hepatic function deteriorated (P=0.001).

CONCLUSION

The detection rates of FLA with CTHA are far higher than those with angiography and dynamic CT. Careful interpretation with recognition of FLA on CTHA images is important, as inadvertent embolization or chemotherapeutic infusion of the FLA may result in supraumbilical skin rash.

Microcoil embolization through a downsized coaxial catheter system: an experimental study

BACKGROUND

Most of the recently developed microcatheters for abdominal angiography still have large diameters at their trailing ends, and thus cannot be used for microcoil embolization in combination with a 3-French (F) system.

PURPOSE

To evaluate the in vitro passage of microcoils through a newly developed 2-F microcatheter (Meister Cath Superselective Plus, MC6) that is compatible with a downsized coaxial catheter system (3-F system) in an experimental study.

MATERIAL AND METHODS

We evaluated the passage of microcoils through MC6 within a blood vessel model using the saline flush technique. Six types of microcoils and 17 size variations (maximal curled diameter 2-10 mm, total length 20-140 mm) were used. We evaluated the passage and post-deployment shape of the microcoils as well as the volume of saline required to flush them.

RESULTS

In the experimental study, all microcoils passed through the MC6 and deployed in a satisfactory manner without catheter occlusion. The mean volumes of saline required to flush the TORNADO (n=1), Reverse TORNADO (n=6), HILAL (n=1), Micronester (n=3), VortX (n=4), and C-Stopper Coil (n=2) were 0.7 ml, 0.58+/-0.20 ml, 0.5 ml, 0.57+/-0.058 ml, 3.5+/-1.5 ml, and 0.70+/-0.14 ml, respectively. There was a statistically significant difference in the mean volume of saline required between the VortX and Reverse TORNADO (P=0.029), and between the VortX and C-Stopper Coil (P=0.031). The VortX required the greatest volume of saline.

CONCLUSION

Microcoil embolization through a 3-F system appears to be feasible for the coils examined in this study.

Portal vein occlusion or stenosis in patients with hepatolithiasis: observation by multiphasic contrast-enhanced CT

AIMS

To analyze the dynamic findings of multiphasic contrast-enhanced CT in hepatolithiasis and to elucidate occlusive changes in portal veins and other associated abnormalities.

METHODS

This was a retrospective study of 25 selected patients with hepatolithiasis who underwent various imaging examinations, including multiphasic contrast-enhanced CT. The following CT findings were evaluated in each of 71 hepatic segments: visualization of a calculus; biliary dilation or focal hepatic atrophy of the affected segment; areas that were abnormally enhanced in the hepatic arterial phase; degrees (normal, stenosis, occlusion) of portal vein calibre; and linear delayed enhancement along the bile-duct walls, suggesting cholangitis.

RESULTS

On CT, calculi were depicted as a hyperdense structures in 61 of 71 segments (86%). Focal hepatic atrophy, which frequently accompanied CT findings suggesting compensatory hypertrophy of other segments, was seen in 50 of 71 segments (70%). Areas that were abnormally enhanced were recognized in 36 of 71 segments (51%). Stenosis or occlusion of portal venous branches was observed in 59 of 71 segments (83%), including 13 segments with occlusion. Findings indicating cholangitis were noted in 50 of 71 segments (70%). The degrees of portal vein calibre were significantly correlated with the presence of hepatic atrophy or cholangitis.

CONCLUSION

Hepatolithiasis is associated with significant rates of stenosis or occlusion of adjacent portal veins as well as hepatic parenchymal changes in the affected area. Chronic deterioration of portal flow may cause these morphological changes.

Liver lesions of visceral larva migrans due to Ascaris suum infection:

The purpose of this study was to analyze computed tomographic (CT) findings of hepatic lesions due to Ascaris suum infection. CT of the liver in three patients, all of whom had immunoserologically confirmed A. suum infection, were retrospectively reviewed. Twenty-five lesions were identified in total. Two radiologists analyzed CT findings in a consensus fashion, with particular interest in the margin, shape, and location of the lesions. Hepatic lesions were ill-defined (22 of 25), small (3-35 mm; average, 11 mm), and nodular (18 of 25) or wedge (three of 25) in shape. Most were located in periportal (16 of 25) or subcapsular (six of 25) regions. Hepatic nodules due to visceral larva migrans of A. suum were located mainly in periportal or subcapsular regions, which may represent periportal eosinophilic granuloma, its pathologic feature. The results were considered to represent the pathophysiology of this entity.

Bilateral ovarian leiomyomas: CT and MRI features

We recently treated a 21-year-old woman with leiomyomas arising from the bilateral ovaries, a very rare condition. On magnetic resonance imaging, more than half of the left adnexal mass showed low signal intensity on T2-weighted images and good enhancement by gadolinium-DTPA, and the remaining part showed high signal intensity on T2-weighted images, so the lesions initially were diagnosed as ovarian fibromas or as thecomas with a certain degree of degeneration. Pathologic examination of the excised tumors proved that they were bilateral ovarian leiomyomas; in addition, the tumor from the left side showed hemorrhagic and myxoid changes with torsion of 180 degrees.

Gluteal muscular and sciatic nerve metastases in advanced urinary bladder carcinoma: case report

We present a case of gluteal muscular and sciatic nerve metastases from urinary bladder carcinoma. T2-weighted magnetic resonance images demonstrated diffuse swelling and an increase in the signal of the right gluteus maximus muscle without destruction of the original arrangement of muscular fibers. Further, remarkable thickening of the right sciatic nerve showing a relatively hypointense signal was detected. Postcontrast T1-weighted images showed strong enhancement of these structures. Fine-needle aspiration biopsy with ultrasonographic guidance confirmed metastatic carcinoma cells in the right gluteal muscle and the sciatic nerve. These radiologic findings may represent a rare pattern of metastasis from urinary bladder carcinoma.

Fat in liver metastasis from renal cell carcinoma detected by chemical shift MR imaging

A case with liver metastasis from papillary renal cell carcinoma (RCC) is presented, in which intratumoral fat was detected on dual-echo chemical shift magnetic resonance imaging (MRI). The preoperative chemical shift MR image of the primary RCC also suggested the presence of intratumoral fat. Liver metastasis from fat-containing RCC should be included in the differential diagnosis of fat-containing liver masses as observed on chemical shift MRI.

Fat detection in gallbladder carcinoma with extensive xanthogranulomatous change demonstrated by chemical shift MR imaging

We present a case of gallbladder carcinoma, in which fat was detected on dual-echo chemical shift magnetic resonance imaging (MRI). Histologic analysis showed poorly differentiated adenocarcinoma associated with massive xanthogranulomatous change. Sudan IV staining successfully confirmed the presence of fat within the interstitial histiocytes. Although rare, gallbladder carcinoma with xanthogranulomatous change should be included in the differential diagnosis of fatty tumor involving the region of the liver as observed on chemical shift MRI.

[A safe and simple method of percutaneous transfemoral implantation of a port-catheter access system for hepatic artery chemotherapy infusion]

The purpose of this study was to perform a simple percutaneous transfemoral implantation of a portcatheter access system using a new catheter coating for hepatic artery chemotherapy infusion, and to evaluate the complications of transfemoral infusion port implantation. The methods of treatment for complications were also studied. The port-catheter system was percutaneously implanted via femoral artery access in 180 patients with malignant liver tumors. Blood flow redistribution was performed using embolization coils. An unfixed 5 Fr catheter was placed in a hepatic artery, and connected to a port implanted subcutaneously below the level of the inguinal ligament. The success rate of implantation was 99%. Complications after placement were observed as follows: port system obstruction (9.6%); dislocation of the catheter tip (8.4%); drug toxicity (4.5%); and infection (3.4%). Notable is the avoidance of cerebral infarcts. In 3 of 17 patients with port obstruction, recanalization of the port was achieved. In 11 of 15 patients with catheter dislocation, replacement of the catheter-port system was successful. In 5 patients with hepatic artery occlusion, the replacement of a microcatheter-port access system was achieved, and hepatic artery chemotherapy infusion was resumed. This percutaneous transfemoral implantation of a catheter-port access system would seem to be a very simple and useful method for many clinical doctors, and it may improve the quality of life in patients with an unresectable malignant liver tumor.

Angiogenesis factors

Angiogenesis is a recent highlight in the medical field; the developmental process and pathological conditions for various diseases can be understood from the novel aspect of "angiogenesis". Many angiogenesis-related factors are involved in the development of vessels during embryogenesis (vasculogenesis), as well as the induction of new vessels in response to physiological or pathological stimuli. In particular, the appearance of hemangioblasts, precursor cells for vascular endothelial cells and blood cells, and blood islands are expected to play a "prelude" role in tubulogenesis. Gene knock out mice of vascular endothelial growth factor (VEGF)/VEGF receptor, ephrin-B2, and angiopoietin-1 results in a failure of normal vessels production. Dormant factors derived from proteolytic cleavage of various physiological substrates are expected to balance a homeostasis of "angiogenic states" in the host. Furthermore, angiogenesis under various pathological conditions of malignant tumors, ocular diseases, psoriasis, rheumatoid arthritis, atherosclerosis and other diseases is associated with complex angiogenesis networks, suggesting pleiotropic mechanisms for angiogenesis.

High expression of the Cap43 gene in infiltrating macrophages of human renal cell carcinomas

We used suppression subtractive hybridization to identify highly expressed genes in the cancerous region of human renal cell carcinoma (RCC) compared with noncancerous tissue. Nine genes were identified to show increased expression in the cancerous region compared with the noncancerous region. The nine genes included thymosin beta4, secreted protein acidic and rich in cysteine (SPARC), Cap43, ceruloplasmin, serum amyloid A, osteopontin, heat shock protein 90 (HSP90), LOT1, and casein kinase I. Of these 9 genes, in situ hybridization with 10 clinical samples consistently showed a strong expression of Cap43 mRNA in infiltrating macrophages in RCCs, but not in cancer cells proliferating in an alveolar pattern. However, Cap43 mRNA was also apparently detected in epithelial cells of the renal proximal tubuli in noncancerous tissue. The higher expression of the Cap43 gene in the cancerous region of RCCs appears to depend on macrophage infiltration. Moreover, treatment with phorbol ester resulted in enhanced expression of the Cap43 gene in human monocytic cells in vitro. The expression of the Cap43 gene in infiltrating macrophages is discussed in association with the differentiated or activated status of monocyte/macrophage.

The specific expression of three novel splice variant forms of human metalloprotease-like disintegrin-like cysteine-rich protein 2 gene inBrain tissues and gliomas

We have previously identified 67 exons on a yeast artificial chromosome contig spanning 1.5 Mb around the multidrug resistance 1 gene region of human chromosome 7q21.1. In this study, we identified three novel cytoplasmic variants (MDC2-gamma, MDC2-delta, and MDC2-epsilon) of the human metalloprotease-like disintegrin-like cysteine-rich protein 2 (MDC2) among these exons by screening a human brain cDNA library and also by using a reverse transcription polymerase chain reaction. Genomic sequence analysis strongly supported the idea that the variations in the cytoplasmic domain were generated by alternative splicing. The expression of MDC2 variant forms in human brain tissue and gliomas was examined by reverse transcription polymerase chain reaction and RNase protection assay. MDC2-epsilon was expressed only in the cortical and hippocampal regions in human brain, but not in gliomas. In contrast, MDC2-gamma was a major form expressed in human gliomas. Specific expression of these cytoplasmic variants of MDC2 in human brain and its malignancies is discussed.

Biological implications of macrophage infiltration in human tumor angiogenesis

Tumor angiogenesis is believed to be induced by increased production of angiogenic factors and decreased production of angiogenic inhibitors by cancer cells, vascular endothelial cells, and other stromal cell types. Most solid tumor cells are surrounded by stroma comprising interstitial connective tissue, blood vessels, fibroblastic cells, etc. Interaction between the stroma and malignant cells appears to have a critical role in the development of tumor neovasculature. We focused on macrophages, which demonstrate wide heterogeneity in biological function and have an essential role in tumor angiogenesis. Macrophages are terminally differentiated cells which produce a number of potent angiogenic cytokines and growth factors such as vascular endothelial growth factor, tumor necrosis factor-alpha, interleukin-8, and basic fibroblast growth factor. They also modulate events in the extracellular matrix through the secretion of extracellular matrix-degrading enzymes and -modulating enzymes. Thus macrophages could influence various stages of angiogenesis either positively or negatively. We found a close correlation between increased macrophage index, malignancy, and high vascular grade in malignant melanoma, and present a model for the possible involvement of activated macrophages in neovascularization in human malignant melanoma.

Macrophage infiltration and heme oxygenase-1 expression correlate with angiogenesis in human gliomas

Macrophages are key participants in angiogenesis. In this study on human brain tumors, we first investigated whether macrophage infiltration is associated with angiogenesis and malignant histological appearance. Immunostaining of macrophages and small vessels in resected glioma specimens indicated that numbers of infiltrating macrophages and small vessel density were higher in glioblastomas than in astrocytomas or anaplastic astrocytomas. Macrophage infiltration was closely correlated with vascular density in human gliomas. Heme oxygenase-1 (HO-1), which is the rate-limiting enzyme in heme catabolism, was also associated with activated macrophages. Expression of mRNA encoding HO-1 was correlated with macrophage infiltration and vascular density in human glioma samples. Infiltrating macrophages were positively stained with anti-HO-1 antibody by immunohistochemical analysis, and in situ hybridization for HO-1 indicated that HO-1 was expressed in infiltrating macrophages in gliomas. HO-1 gene may be a useful marker for macrophage infiltration as well as neovascularization in human gliomas.

Novel biological functions of interleukin-4: formation of tube-like structures by vascular endothelial cells in vitro and angiogenesis in vivo

The effect of interleukin-4 (IL-4) on angiogenesis was studied in vitro and in vivo. Human recombinant IL-4 significantly stimulated the formation of tube-like structures in collagen gels by bovine aortic endothelial cells as well as by human microvascular endothelial cells. Human recombinant IL-4 at 50-500 U/ml stimulated by about two- to threefold the formation of tubes by bovine aortic endothelial cells; the rate was comparable to that of basic fibroblast growth factor. Tube formation was almost completely inhibited by the addition of IL-4 receptor neutralizing antibody. Administration of rat recombinant IL-4 led to neovascularization when implanted in the rat cornea. Findings suggest that IL-4 may be a mediator of the immune system as well as an inducer of angiogenesis.

Treatment of hepatic encephalopathy by retrograde transcaval coil embolization of an ileal vein-to-right gonadal vein portosystemic shunt

A 43-year-old non-cirrhotic woman suffered from encephalopathy caused by an extrahepatic portosystemic shunt between the ileal vein and inferior vena cava via the right gonadal vein. Percutaneous transcatheter embolization with stainless steel coils was performed by the retrograde systemic venous approach. Encephalopathy improved dramatically.