Abstract P2-06-01: Ki67 Proliferative Index as an Invaluable Biomarker in Hormone Receptor (HR)-Positive Breast Cancer: Ki67 Labelling Index Can Reflect the Differences between Luminal A and B Subtypes Better Than HER2 Expression

Background: Differentiation by multigene signatures with excellent performance of hormone receptor (HR)-positive BC largely related to their proliferation genes. Despite questions about its usefulness, there is increasing evidence that Ki67 is a valuable prognostic marker. Standardization of Ki67 pathological assessment is the main problem to interpret reported trials.

The aims of the study are to evaluate the role Ki67 as prognostic marker to predict relapse in HR-positive BC patients (luminal A and B) in adjuvant setting using prospective patients’ cohort. In addition, cut-off value and significant level of Ki67 were investigated comparing with other biomarkers including HER2 in luminal BCs.

Method: We retrospectively analyzed the clinicopathologic characteristics of 1,070 postoperative breast cancer patients including Ki67 and clinical outcomes in terms of relapse free survival (RFS) between 2004 and 2007 at the Samsung Medical Center. Ki67 labelling index was measured in quantitative and semiquantitative method, independently. The percentage of positive nuclei stained for Ki67 was calculated each section based on the approximately 1,000 carcinoma cell nuclei. In addition, Ki67 was graded on a scale from 0 to 4, where 0 = staining of 0-4% of tumor cells, 1 = staining of 5-25% of tumor cells, 2 = 26-50% of tumor cells, 3 = staining of 51-75% of tumor cells, and 4 = staining of more than 76% of tumor cells. ROC curve was drawn to evaluate the usefulness of Ki67 index to get AUC then, find out the proper cut-off value of Ki67 to predict relapse. Multivariate analyses with Cox-regression model were performed. Results: Among 1,564 patients who received curative surgery for invasive breast cancer from January 2004 to June 2007, 1,070 patients with HR-positive were included in this analysis excluding 494 with HER2-enriched or triple negative breast cancer patients. Median follow-up duration was 56.9 months (range 36-77 months). Median age was 46 years (range 22-83 years). Ki67 threshold >19.5%, corresponding to a sensitivity 78.3%, a specificity 51.6% was chosen as cut-off value for relapse in adjuvant patients’ cohort. The AUC was 0.689 (P<0.0001 by Mann-Whitney U test). Overall relapse rate was 5.6%. In univariate analysis by log-rank test for relapse, ER negativity (p=0.010), HER2 positivity (p=0.017), histologic (p=0.001), and nuclear grade (p=0.012), lymphovascular invasion (P<0.0001), TNM stage (0.001), and Ki67 (P<0.0001) were identified risk factors to predict relapse. However, ER negativity, Ki67, and stage were identified as independent risk factors for relapse (Hazard Ratio (HR) 2.7, p=0.031 for ER negativity, HR 3.4, p <0.0001 for Ki67, HR 1.6, p=0.017 for stage) in Cox-regression multivariate analysis. Conclusion: Ki67 could strongly predict clinical outcomes for patients with luminal. 19.5% may be useful cut-off value of Ki67 labelling index. Ki67 may be a better biomarker to predict clinical outcomes than HER2 expression in luminal BCs. ER-/PR+ subset probably has different biology with other luminal BCs. Prospective clinical trials to choose therapeutic option using Ki67 are warranted.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P2-06-01.

Abstract P5-05-13: HER2-Induced MMP-1 Expression Is Mediated by HER1 Though AR, EGF, and TGF Independent of HER3 through HRG in Breast Cancer Cells

introduction. However, one of plausible explanation for resistance to trastuzumab is associated with HER dimerization. Furthermore, HER3 seems to be the preferred dimerization partner when signaling occurs through the PI3K pathway and, as such, is emerging as a key target for inhibition of HER signaling. Recently, we reported that HER2 could induce enhanced MMP-1 expression. In addition, this up-regulation of MMP1 expression was shown to be mediated MAPK pathway synergized with ER. Heregulin (HRG) acts as a preferential ligand for HER3 and/or HER4 receptors. Upon binding, HRG activates the EGFR/HER2 receptors via dimerization with HER3 and/or HER4. In the other words, HRG-β was reported to promote MMP-7 expression via HER2-mediated AP-1 activation in MCF-7 cells. In addition, MMP-9 is associated with HRG-≥1/HER2 aggressive phenotype of breast cancer.

Based on these backgrounds, we conducted this study to test the role of HER3 in breast cancer cells in relation to the expression of HER2 and MMP-1.

Our result showed that MMP-1 and MMP-13 expressions were up-regulated via EGF and amphiregulin (AR) independent of HRG in HER2 transfected MCF-7 and SK-BR-3 breast cancer cells through Western immunoblotting and quantitative RT-PCR. Enhanced MMP-1 and MMP-13 expressions were markedly decreased by treating HER2 targeting agents in AR, EGF, and TGF-β stimulating cell lines, while these findings were not observed in HRG1-β and HRG1-β stimulating cell lines in quantitative RT-PCR. In addition, these findings were reversed by treating siEGFR and siHER2, not by siHER3. Consequently, we could confirm the downstream pathways were mediated by MMP-1 AP-1 not by HRG1-β, nor HRG1-β with EMSA.

This study showed that HER2-induced MMP-1 expression was mediated by HER1 though AR, EGF, and TGF independent of HER3 through HRG in breast cancer cells. This result implies that the dimerization responsible for MMP-1 up-regulation by HER2 is HER1/HER2, not HER2/HER3. Further implications of MMP-1 in HER2 overexpressing breast cancer through HER1 are going to following.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P5-05-13.

Abstract P6-13-05: Differences of Clinical Manifestations and Therapeutic Outcomes in Leptomeningeal Metastases (LM) According to Breast Cancer Subtypes

Backgrounds: Breast cancer is the solid tumor most commonly associated with leptomeningeal metastases (LM). Therapeutic modalities include intrathecal and systemic chemotherapy, radiotherapy and other palliative modality including placement of a ventricular reservoir. The aim of this study is to characterize clinical feature and outcomes of LM according to breast cancer subtypes in conjunction with whole CNS metastases.

Methods: A retrospective study was performed on breast cancer patients with LM who received palliative management at Samsung Medical Center between 1994 and 2008. Among 281 metastatic breast cancer patients, 71 breast cancer patients with LM were identified. They were divided into three biological subgroups. The propensity of biological subtypes for LM, clinical manifestation including recursive partitioning analysis of Radiation Therapy Oncology Group (RPA RTOG) prognostic class, and therapeutic outcomes were assessed.

Results: The median age was 48 (range 26-70) years. The rates of the patients with triple negative breast cancer (TNBC), human epidermal growth factor receptors 2 (HER2)-positive and hormone receptor (HR)- positive subtype breast cancer were 26 (44%), 15 (25%) and 18 (31%), respectively. Sixty-four patients (90%) had metastatic disease at sites other than LM. TNBC were more common in RPA RTOG prognostic class III than those in HER2 and HR-positive subtypes (61% vs 39% vs 0%, P<0.0001). CNS including LM was the first site of distant metastasis in 65% of the TNBC patients. Treatment includes intrathecal chemotherapy (IT), whole brain radiotherapy (WBRT), and systemic chemotherapy. The median survival duration from the diagnosis of LM to death (OS-LM) was 4.5 months (range 0.2-26.4 months). Main causes of death were deterioration of neurologic sequelae associated with LM (55%), systemic disease progression (27%), and et cetera (18%). Death rates related with LM at each subtype were 64% for TNBC, 36% for HER2-positive, and 0% for HR-positive patients (p=0.060). In the univariate analysis, RPA RTOG classification (p=0.003), systemic disease control at LM (p=0.041), cytologic negative conversion to IT (p=0.001), systemic chemotherapy after LM diagnosis (p=0.002), and combined modality for LM treatment (p=0.005) were singled out as having prognostic value for OS-LM. Cox-regression multivariate analysis showed that RPA class (HR (Hazard Ratio) 1.8, p=0.022), cytologic negative conversion to IT (HR 0.4, p=0.043), and systemic chemotherapy (HR 0.24, p=0.004) are identified as independent prognostic factors.

Conclusion: TNBC and HER2-positive breast cancer appeared to have special predilection for LM as well as brain parenchymal metastases. High RPA class of TNBC may reflect more aggressive tumor biology in this sanctuary area. OS-LM depended on RPA class, cytologic negative conversion, and the use of systemic chemotherapy. The role of systemic chemotherapy and active local treatment modalities according to subtypes should be defined to improve dismal prognosis.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P6-13-05.

The CT and F-FDG PET/CT appearance of primary renal malignant fibrous histiocytoma

Renal malignant fibrous histiocytoma (MFH) is a rare, primary renal tumour. Imaging findings of renal MFH, including ultrasound, CT and MRI, have, however, been reported. As to the best of our knowledge (18)F-FDG PET/CT imaging of renal MFH has not been previously reported, we present the CT and (18)F-FDG PET/CT appearance of a pathologically proven primary renal MFH.

In vitro antimicrobial effect and in vivo preventive and therapeutic effects of partially purified lantibiotic lacticin NK34 against infection by Staphylococcus species isolated from bovine mastitis

Lantibiotics are small (<5 kDa), polycyclic peptides produced by gram-positive bacteria; they are also known as gram-positive bacteriocins. The high antimicrobial activity of lacticins and the continuing appearance of antibiotic-resistant bacteria in recent years have resulted in a renewed interest in lantibiotics. A partially purified form of lacticin NK34 (a Lactococcus lactis product isolated from the Korean fermented fish jeotgal) was tested to determine its antimicrobial effects against Staphylococcus aureus (n=20) and coagulase-negative Staphylococcus (CNS, n=20) strains isolated from the raw milk of cows with subclinical bovine mastitis in the present study. The spot-on-lawn assay was used to identify the 2 strains from each group with the greatest lacticin NK34 susceptibility, and the minimal lethal dose (MLD) was measured in ICR (imprinting control region) mice. The preventive and therapeutic effects of lacticin NK34 on the mouse infection model were determined for the first time. Lacticin NK34 demonstrated antimicrobial effects in 14 of 20 (70%) S. aureus indicator strains and in 18 of 20 (90%) CNS strains. Staphylococcus aureus 69 and S. simulans 55 demonstrated the greatest susceptibility to lacticin NK34 in the spot-on-lawn assay. The S. aureus 69 MLD was measured at 1.53 x 10(9) cfu/mouse, whereas the S. simulans 55 MLD was 3.59 x 10(9) cfu/mouse. Mice infected experimentally with S. aureus 69 MLD or S. simulans 55 MLD were treated with lacticin NK34. Treated mice demonstrated an 80% survival rate (48 of 60 mice) compared with a survival rate of 7.5% (3 of 40 mice) in control mice treated with distilled water. These data suggest that lacticin NK34 might be useful in the control of bovine mastitis and systemic bacterial infection.

Distribution of streptogramin resistance genes and genetic relatedness among quinupristin/dalfopristin-resistant Enterococcus faecium recovered from pigs and chickens in Korea

Fifty-four quinupristin/dalfopristin-resistant Enterococcus faecium (QDREF) isolated from chickens and pigs during 2002-2003 in Korea were screened by PCR for the presence of streptogramin resistance genes vatD, vatE, and vgbA, and macrolide resistance gene ermB. None of the QDREF isolates carried vgbA and vatD genes, while vatE and ermB were detected in 9.2% and 74% of the isolates, respectively. Twenty-six percent (14/54) of the QDREF isolates contained none of the resistance determinants tested. Pulsed-field gel electrophoresis (PFGE) patterns revealed high heterogeneity: 47 different patterns for 54 QDREF evaluated. Identical PFGE types were observed in two pairs of chicken isolates and a pair of pig isolates, respectively, but chicken isolates did not share PFGE pattern with pig isolates, suggesting clonal spread of QDREF strain between the same species of animals but not between different species of animals. This is the first report, to our knowledge, of vatE-positive E. faecium isolates and also the first evidence of clonal spread of QDREF strain between animals in Korea.

Palliative atrial switch operation in a 22-year-old patient with transposition of the great arteries

A 2-year-old boy was diagnosed as having transposition of the great arteries (TGA) and ventricular septal defect (VSD) and underwent pulmonary artery banding. The patient showed slow progression of cyanosis and dyspnea on exertion. Oxygen saturation was 70-75 % and cardiac catheterization showed severe pulmonary hypertension. At the age of 22, the patient underwent a palliative atrial switch operation; oxygen saturation increased to around 95 % and the patient experienced relief of symptoms. Atrial fibrillation and right side pleural effusion occurred but resolved and the patient was discharged.

Vector prime protein boost vaccination in the setting of myeloablative-induced lymphopenia suppresses growth of leukemia and solid tumors

We have developed a vaccine, which is designed to induce tumor-associated antigen (TAA)-specific T cells and antibodies in the setting of profound lymphopenia induced by myeloablative therapy and T-cell-depleted bone marrow transplantation. Test mice were injected subcutaneously (sc) with the 32DP210Bcr-Abl cell line, which is positive for the p210Bcr-Abl protein (Group 1). In Group 2, 7 days after injection of the 32DP210Bcr-Abl positive cell line, the mice received 900 cGy total body irradiation (TBI) followed in 1 h by the intravenous infusion of 10 million T-cell-depleted syngeneic bone marrow cells (TCDBMT) (Group 2). The leukemia-bearing group received an intravenous injection of 10 million spleen cells (donor lymphocyte infusions) from unvaccinated (Group 3) and TAA/ecdCD40L-vaccinated (Group 4) syngeneic mice 3 days after completion of the TBI and TCDBMT. Groups 3 and 4 mice received three additional sc vaccinations at 7-day intervals with the TAA/ecdCD40L vaccine, in which the TAA was taken from the junctional peptide of the P210bcr-Abl protein. The survival of Groups 3 and 4 mice was significantly longer than that in Groups 1 and 2 mice. Vaccinated mice from Group 4, which developed complete responses, survived up to 350 days post-injection of the leukemia cells without any evidence of leukemia regrowth.

Improved islet yields after purification following the novel endogenous trypsin inhibitor and histidine-tryptophan-ketoglutarate treatment in pigs

BACKGROUND

Adult porcine islet xenotransplantation into humans is greatly diminished by the difficulty to isolate islets because of their fragility. The goal of this study was to improve the efficacy of islet yields using endogenous trypsin inhibitor and histidine-tryptophan-ketoglutarate (HTK) perfusate.

METHOD

We compared two porcine islet isolation protocols: Eurocollins solution for in situ pancreas perfusion without use of an endogenous trypsin inhibitor versus HTK solution including endogenous trypsin inhibitor for pancreas perfusion.

RESULTS

Endogenous trypsin inhibitor and HTK strategies significantly improved total islet yield, recovery, and islet index after purification (P < .05), whereas unpurified islet yield did not increase. An average of 228,000 +/- 95,000 islet equivalents (IEQ) (n = 20) purified islets were obtained in the first group compared with 115,000 +/- 56,000 IEQ (n = 18) in the second group. The average islet index was significantly increased in the first group compared with the second group before and after purification: before: 0.28 versus 0.49 versus after: 0.25 versus 0.4 (P < .05). At this time, islet purity, viability, and stimulation index did not show a significant difference between groups.

CONCLUSION

Our study showed that endogenous trypsin inhibitor and HTK strategies significantly improved purified islet isolation efficacy because of reduction of islet fragility.

Experimental microencapsulation of porcine and rat pancreatic islet cells with air-driven droplet generator and alginate

Transplantation of microencapsulated islets is proposed as an ideal therapy for the treatment of type 1 diabetes mellitus without immunosuppression. This strategy is based on the principle that foreign cells are protected from the host immune system by an artificial membrane. The aim of this study was to establish an ideal condition of microencapsulation using an air-driven droplet generator and alginate in vitro. The optimal conditions for islet encapsulation were an alginate inflow rate of 10 mL/h, CO2 flow rate of 2.0 L/min in a concentration of 2% alginate. For 2.5% alginate, the alginate inflow rate of 20 mL/h, CO2 flow rate 3.0 L/min was ideal; alginate inflow rate of 40 mL/h, CO2 flow rate of 4.0 L/min showed good microcapsules at 3% alginate. Viability of encapsulated islets was greater than 90%. In terms of insulin secretion, encapsulated islets secreted insulin in response to glucose in static culture medium. However, there was no normal response to low or high glucose challenge with a stimulation index less than 2.0. Microencapsulation of pig islets was successfully performed with air-driven droplet generator and alginate in vitro. Further studies about biocompatibility and glucose control in vivo may provide a useful tool for treatment of patients with diabetes mellitus.

Sterilization effect of atmospheric plasma on Escherichia coli and Bacillus subtilis endospores

AIMS

Escherichia coli and Bacillus subtilis spores were treated with an atmospheric plasma mixture created by the ionization of helium and oxygen to investigate the inactivation efficiency of a low-temperature plasma below 70 degrees C.

METHODS AND RESULTS

An electrical discharge plasma was produced at a radio frequency (RF) of 13.56 MHz, connected to a perforated circular electrode with a discharge spacing of 1-15 mm. The discharge gas was helium with 0-2% oxygen. For the plasma treatment, a dried E. coli cell or B. subtilis endospore suspension on a cover-glass was exposed to oxygen downstream of the plasma from holes in an RF-powered electrode. The sterilization effect of the RF plasma was highest with 0.2% oxygen, corresponding to the maximum production of oxygen radicals.

CONCLUSIONS

Oxygen radicals generated by RF plasma are effective for the destruction of bacterial cells and endospores.

SIGNIFICANCE AND IMPACT OF THE STUDY

Low-temperature atmospheric plasma can be used for the disinfection of diverse objects, especially for the inactivation of bacterial endospores.

Antibiogram and coagulase diversity in staphylococcal enterotoxin-producing Staphylococcus aureus from bovine mastitis

We investigated antibiogram and coagulase gene diversity in staphylococcal enterotoxin (StE)-producing Staphylococcus aureus isolated from raw milk samples of cows infected with mastitis from 140 dairy farms in Korea between 1997 and 2004. Of the 696 Staph. aureus isolates collected in this study, 164 isolates (23.6%) produced one or more staphylococcal enterotoxins (A to D), and 19 isolates (2.7%) were methicillin-resistant. The percentage of StE-producing Staph. aureus (SES) isolates resistant to methicillin, kanamycin, neomycin, amikacin, and tetracycline was greater than that of non-SES. Ten coagulase genotype patterns were observed, including 4 main types comprising I (25.4%), II (13.9%), VII (13.2%), and VIII (17.8%). More than 4 Staph. aureus types were isolated from each of 82 dairy farms in different geographic locations, and only 1 coagulase genotype pattern was observed in 39 of the herds (47.6%). There was no significant correlation between coagulase genotypes harbored by Staph. aureus and their specific StE type. The percentage of isolates producing major StE types (A, B, AC, and ABCD) and being resistant to cephalothin and methicillin was greater among the Staph. aureus isolates with the 4 predominant coagulase genotypes (I, II, VII, and VIII) than among the isolates harboring the 6 rare coagulase types (III, IV, V, VI, IX, and X). Based on coagulase gene polymorphisms, our data indicate that a broad distribution of identical or closely related enterotoxin-producing Staph. aureus strains seem to contribute to bovine mastitis in the Republic of Korea.

Phenotypic and genetic antibiogram of methicillin-resistant staphylococci isolated from bovine mastitis in Korea

Staphylococcus aureus belongs to the group of major contagious mastitis pathogens, whereas the coagulase-negative staphylococci (CNS) are also capable of causing opportunistic bovine mastitis. Many of these strains are resistant to penicillin or ampicillin because of the long-term use of beta-lactam antibiotics in agricultural and healthcare settings. Based on the simple and highly specific coagulase genotyping by PCR-RFLP used for discriminating among Staph. aureus strains, the relationship between phenotypic antibiogram and the polymorphism of coagulase gene was determined in this study. The staphylococci strains (835 Staph. aureus and 763 CNS) were isolated from 3,047 bovine mastitic milk samples from 153 dairy farms in 8 provinces from 1997 to 2004 in the Republic of Korea. Twenty-one (2.5%) Staph. aureus and 19 (2.4%) CNS strains were resistant to methicillin [oxacillin minimum inhibitory concentration (MIC) > or = 4 microg/mL]. The mecA gene was also found in 13 methicillin-resistant Staph. aureus (MRSA) and 12 methicillin-resistant CNS (MRCNS) isolates with a significantly higher detection rate of the mecA gene in MRSA with high MIC (> or = 16 microg/mL) compared with those with MIC < or = 8 microg/mL. Methicillin-resistant Staph. aureus and MRCNS were also more resistant to other antibiotics (ampicillin, cephalothin, kanamycin, and gentamicin) than methicillin-susceptible staphylococci. Among 10 different coa PCR-RFLP patterns (A to J) in 706 Staph. aureus strains, the main types were A (26.9%), B (17.0%), G (10.5%), and H (15.4%), with the frequent observation of the A and H types (6 and 10 isolates) in MRSA. This study indicates that major epidemic Staph. aureus clones may be spread between different dairy farms, and the profile of coa genotype can be applied for epidemiological investigations and control of bovine mastitis, particularly one caused by MRSA with specific prevalent coa types.

The analysis of milk components and pathogenic bacteria isolated from bovine raw milk in Korea

Bovine mastitis can be diagnosed by abnormalities in milk components and somatic cell count (SCC), as well as by clinical signs. We examined raw milk in Korea by analyzing SCC, milk urea nitrogen (MUN), and the percentages of milk components (milk fat, protein, and lactose). The associations between SCC or MUN and other milk components were investigated, as well as the relationships between the bacterial species isolated from milk. Somatic cell counts, MUN, and the percentages of milk fat, protein, and lactose were analyzed in 30,019 raw milk samples collected from 2003 to 2006. The regression coefficients of natural logarithmic-transformed SCC (SCCt) on milk fat (-0.0149), lactose (-0.8910), and MUN (-0.0096), and those of MUN on milk fat (-0.3125), protein (-0.8012), and SCCt (-0.0671) were negative, whereas the regression coefficient of SCCt on protein was positive (0.3023). When the data were categorized by the presence or absence of bacterial infection in raw milk, SCCt was negatively associated with milk fat (-0.0172), protein (-0.2693), and lactose (-0.4108). The SCCt values were significantly affected by bacterial species. In particular, 104 milk samples infected with Staphylococcus aureus had the highest SCCt (1.67) compared with milk containing other mastitis-causing bacteria: coagulase-negative staphylococci (n = 755, 1.50), coagulase-positive staphylococci (except Staphylococcus aureus; n = 77, 1.59), Streptococcus spp. (Streptococcus dysgalactiae, n = 37; Streptococcus uberis, n = 12, 0.83), Enterococcus spp. (n = 46, 1.04), Escherichia coli (n = 705, 1.56), Pseudomonas spp. (n = 456, 1.59), and yeast (n = 189, 1.52). These results show that high SCC and MUN negatively affect milk components and that a statistical approach associating SCC, MUN, and milk components by bacterial infection can explain the patterns among them. Bacterial species present in raw milk are an important influence on SCC in Korea.

Prognostic significance of p53 gene mutations and protein overexpression in localized gastrointestinal stromal tumours

AIMS

Mutation of c-kit is a relatively early event in the tumorigenesis of gastrointestinal stromal tumours (GISTs). The aim was to determine the prognostic significance of p53 alterations as an additional genetic change in GISTs.

METHODS AND RESULTS

We reviewed 125 patients with localized GISTs subjected to complete resection between 1990 and 2002. Mutational analyses of c-kit exons 9, 11, 13 and 17, p53 exons 4-8 and immunohistochemistry for p53 protein were conducted using paraffin-embedded tissues. Alterations of p53 were observed in 50 patients (40.0%). Based on the National Institutes of Health's risk category, p53 alterations were noted more frequently in the higher risk categories (P = 0.041). With a median follow-up of 56.5 months (range: 2.3-126.8), 5-year relapse-free survival (RFS) rates were 61.7% without p53 alterations, compared with only 40.2% with p53 alterations (P = 0.009). Multivariate analysis indicated that p53 alterations comprised an independent, poor prognostic factor for RFS, in addition to c-kit mutations, large size, a high mitotic count and non-gastric primary sites.

CONCLUSIONS

Alterations in p53 were more commonly observed in localized GISTs at higher risk of relapse. This suggests that they are significant as an independent, poor prognostic factor.

Varying degrees of FDG uptake in multiple benign neurofibromas on PET/CT

We report fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) findings of three neurofibromas in the mediastinum and neck in a 26-year-old woman with neurofibromatosis type 1. PET/CT scans demonstrated varying degrees of FDG uptake with maximum standard uptake values (SUV(max)) of 5.3, 1.8 and 3.2 for left lower neck, left paratracheal and right paravertebral masses, respectively. Surgical resections were carried out and histopathology confirmed three benign neurofibromas with various tissue components and cellularities.

Application of a New Portable Microscopic Somatic Cell Counter with Disposable Plastic Chip for Milk Analysis

The somatic cell count (SCC) is one of the international standards for monitoring milk quality, and it is a useful indicator of mastitis. The current reference method for determining the SCC in raw milk is direct microscopic analysis, but this method requires well-trained staff to maintain its accuracy and reproducibility. To overcome these inconveniences, we developed a portable system (the C-reader system) that utilizes the capillary flow of a microfluidic chamber by surface modification of the hydrophilicity. The microfluidic technology of disposable microchips allows for low consumption of reagents, and a combination of ready-to-use reagents makes the daily work easier. The repeatability test of the C-reader using 10 composite bovine milk samples satisfied the recommended values for SCC equipment. In addition, an acceptable accuracy level of the natural logarithmic-transformed SCC [ln(SCC/1,000): +/- 0.059 to 0.112] was achieved using composite raw milk samples and various somatic cell standard solutions from the American Eastern Laboratory and the Korean National Veterinary Research and Quarantine Service. After testing 875 composite milk samples, the C-reader showed a high correlation coefficient (R2 = 0.935 to 0.964) and a low mean difference value in log-transformed SCC (-0.088 to 0.004) compared with 3 automatic commercialized somatic cell counters (Fossomatic 4000, Somacount 150, and Somascope). In conclusion, the C-reader system is a new, easy-to-use automatic on-farm method with acceptable repeatability and accuracy for measuring SCC in large dairies and smaller laboratories.

Evaluation of the photoneutron field produced in a medical linear accelerator

The doses and spectra of photoneutrons produced in a medical linear accelerator with photon energies of 10 and 15 MV were evaluated. The Monte Carlo code, MCNPX, was used to simulate the transport of these photoneutrons around the head for 10 and 15 MV photons. The fully-described geometry of the accelerator head was used in this calculation. The photoneutron energy spectra and doses for various photon field sizes were calculated at each of 20 positions. The results indicate that the maximum dose equivalents are observed in 20 x 20 cm(2) case among photon fields. It was found the neutron average energy at isocenter for a 0 x 0 cm(2) field is 0.38 MeV for 10 MV and is 0.45 MeV for 15 MV. The neutron doses at 10 positions around the head in the treatment room of the operation facility at 10 and 15 MV were measured using the bubble detectors. Measurements were compared with the calculations under the same geometry in the experiment. It was found that the majority of the calculated results agreed to within the standard deviations of the measurements. These above results can be applied in the verification of maximum allowed neutron leakage percentage of treatment dose defined in the IEC. We have been employing them to derive the empirical formula for neutron dose equivalent level at the maze entrance of medical accelerator treatment rooms in a study that is still underway.

High-dose chemotherapy with autologous stem cell transplantation in extranodal NK/T-cell lymphoma: a retrospective comparison with non-transplantation cases

To determine the role of high-dose chemotherapy and autologous stem cell transplantation (HDC/ASCT) in extranodal NK/T-cell lymphoma patients, we conducted a retrospective analysis. In our previous study, we searched for patients who had received HDC/ASCT and identified 16 eligible patients and compared the treatment outcome with historical control group (n=246). Nine patients received HDC/ASCT in the first (CR1) or second complete remission (CR2), while seven patients received HDC/ASCT as salvage. Twelve of 16 patients achieved or maintained CR after HDC/ASCT. Among the 12 patients, five patients relapsed. Estimated 2-year overall survival (OS) and relapse-free survival (RFS) rates were 71.3+/-12.4% and 25.8+/-14.3%, respectively. There was a tendency of better survival in patients who received HDC/ASCT as compared to those who did not (P=0.091). In subset analysis, patients who underwent HDC/ASCT at CR (P=0.049) and patients with stage III or IV (P=0.001) had a favorable outcome. Patients with NKIPI 3,4 or EUNKTL, who underwent HDC/ASCT had more prolonged survival without statistical significance (P=0.055 and 0.056). In conclusion, HDC/ASCT may be considered as a treatment option for patients with extranodal NK/T-cell lymphoma, especially those in CR, with advanced disease (stage III/IV or EUNKTL) and high NKIPI scores.

A phase II study of capecitabine plus 3-weekly oxaliplatin as first-line therapy for patients with advanced gastric cancer

Capecitabine plus oxaliplatin every 3 weeks (XELOX regimen) has proven efficacy in patients with colorectal carcinoma. We investigated this combination in patients with previously untreated advanced gastric carcinoma. The study population comprised patients with histologically confirmed nonresectable advanced gastric adenocarcinoma. Patients received intravenous oxaliplatin 130 mg m(-2) over 2 h on day 1 plus oral capecitabine 1000 mg m(-2) twice daily on days 1-14, every 3 weeks. Patients received a maximum of eight cycles. Twenty evaluable patients (17 men, 3 women) with a median age of 64 years (range 38-75) were enrolled. The overall response rate was 65% (95% confidence interval (CI), 44-86%), with complete responses in two patients and partial responses in 11 patients. Median progression-free survival was 7.5 months (95% CI, 3.2-11.7 months); median overall survival was not reached during the study period. There was no grade 4 and little grade 3 toxicity. The most common haematological adverse event was anaemia (65% of patients) and the most common nonhaematological toxicities were vomiting (65%), neuropathy (60%), diarrhoea (30%), and hand-foot syndrome (20%). In conclusion, XELOX is apparently as effective as triplet combinations and is well tolerated as first-line therapy for advanced gastric carcinoma. We are starting a large multi-institutional phase II study of XELOX in this setting.

Sleep-related nocturnal erections and erections during midazolam-induced sedation in healthy young men

This study was performed to evaluate the characteristics of penile erection during midazolam-induced sedation after nocturnal sleep deprivation (NSD) and to determine the effect of NSD on erectile episodes in healthy, sexually functional young men. This procedure might possibly prove to be a brief office-based method of assessing whether erectile dysfunction is psychogenic or biogenic. Nineteen volunteers between the ages of 20 and 29 years participated in this study. We measured the morning penile erection after midazolam (3-5 mg) administration intravenously and all subjects completed 42 tests. Of 42 test, 28 tests revealed erectile episodes, whereas no erectile episodes were observed in 14 tests. Nocturnal sleep deprivation rate was significantly higher in tests with erectile episodes than in tests without erectile episode (P=0.030). Test order or duration of test was not different between two test results. Number of erectile episodes (r=0.374, P=0.015), tip radial rigidity (r=0.412, P=0.007), base radial rigidity (r=0.366, P=0.017) and tip tumescence (r=0.447, P=0.003) correlated with the degree of NSD. When we determined whether NSD was discriminative with regard to erectile episodes, the area under the receiver operating characteristic curve was calculated at 0.705 (95% confidence interval, 0.527-0.883; P=0.032) for the possibility of erectile episodes. Nocturnal sleep deprivation might recover the inhibited rapid eye movement sleep during midazolam-induced sedation. Our findings suggest that erection monitoring during midazolam-induced sedation after NSD may be convenient. However, validation of midazolam-induced morning penile tumescence monitoring with a large population is mandatory.

The effect of Epstein-Barr virus status on clinical outcome in Hodgkin's lymphoma

The association of Epstein-Barr virus (EBV) with Hodgkin's lymphoma (HL) has been investigated over the last few years. The impact of EBV on clinical outcome is still controversial, however. In this study, we investigated the effect of EBV status on clinical outcome of HL patients. Between January 1986 and September 2004, fifty-six patients, diagnosed as having HL, were included in the analysis. Clinical data were reviewed retrospectively from the patients' records. Tissues from 56 patients were analyzed for the presence of EBV using the in situ hybridization (ISH) for EBV-encoded RNA (EBER) and immunohistochemistry for latent membrane protein (LMP)1. EBV infection was identified in 41.1% of cases by EBER ISH, 26.8% by LMP1 expression, and 26.8% by LMP1 and EBER ISH. EBER-positive HL were significantly more frequent in mixed cellularity (MC) subtype (P=0.014) and advanced stage (P=0.034). There was a trend toward shorter overall survival in EBER-positive patients without statistical significance (P=0.238). LMP1 expression also correlated with MC subtype (P=0.006) and advanced stage (P=0.007), although it did not significantly influence the survival outcome. In subgroup analysis, both EBER and LMP1 positivities were associated with longer progression-free survival in patients with age <25 years old (P=0.045). Reverse trends were shown in patients > or =25 years old. In this study, we demonstrated that the impact of tumor EBV status on prognosis may be age dependent and young patients with latent EBV infection have favorable prognosis.