Quantitative apparent diffusion coefficients in the characterization of brain tumors and associated peritumoral edema

BACKGROUND

Conventional magnetic resonance (MR) imaging has a number of limitations in the diagnosis of the most common intracranial brain tumors, including tumor specification and the detection of tumoral infiltration in regions of peritumoral edema.

PURPOSE

To prospectively assess if diffusion-weighted MR imaging (DWI) could be used to differentiate between different types of brain tumors and to distinguish between peritumoral infiltration in high-grade gliomas, lymphomas, and pure vasogenic edema in metastases and meningiomas.

MATERIAL AND METHODS

MR imaging and DWI was performed on 93 patients with newly diagnosed brain tumors: 59 patients had histologically verified high-grade gliomas (37 glioblastomas multiforme, 22 anaplastic astrocytomas), 23 patients had metastatic brain tumors, five patients had primary cerebral lymphomas, and six patients had meningiomas. Apparent diffusion coefficient (ADC) values of tumor (enhancing regions or the solid portion of tumor) and peritumoral edema, and ADC ratios (ADC of tumor or peritumoral edema to ADC of contralateral white matter, ADC of tumor to ADC of peritumoral edema) were compared with the histologic diagnosis. ADC values and ratios of high-grade gliomas, primary cerebral lymphomas, metastases, and meningiomas were compared by using ANOVA and multiple comparisons. Optimal thresholds of ADC values and ADC ratios for distinguishing high-grade gliomas from metastases were determined by receiver operating characteristic (ROC) curve analysis.

RESULTS

Statistically significant differences were found for minimum and mean of ADC tumor and ADC tumor ratio values between metastases and high-grade gliomas when including only one factor at a time. Including a combination of in total four parameters (mean ADC tumor, and minimum, maximum and mean ADC tumor ratio) resulted in sensitivity, specificity, positive (PPV), and negative predictive values (NPV) of 72.9, 82.6, 91.5, and 54.3% respectively. In the ROC curve analysis, the area under the curve of the combined four parameters was the largest (0.84), indicating a good test.

CONCLUSION

Our results suggest that ADC values and ADC ratios (minimum and mean of ADC tumor and ADC tumor ratio) may be helpful in the differentiation of metastases from high-grade gliomas. It cannot distinguish high-grade gliomas from lymphomas, and lymphomas from metastases. ADC values and ADC ratios in peritumoral edema cannot be used to differentiate edema with infiltration of tumor cells from vasogenic edema when measurements for high-grade gliomas, lymphomas, metastases, and meningiomas were compared.

A possible association between schizophrenia and GRIK3 polymorphisms in a multicenter sample of Scandinavian origin (SCOPE)

There is considerable evidence of altered glutamatergic signalling in schizophrenia and a polymorphic variant of the GRIK3 glutamate receptor gene on 1p34-33 has previously been associated to this psychotic disorder. We therefore conducted a systematic association study with 30 HapMap-selected tagging SNPs across GRIK3 in three independent samples of Scandinavian origin from the Scandinavian Collaboration of Psychiatric Etiology (SCOPE), including a total of 839 cases with schizophrenia spectrum and 1473 healthy controls. Four markers (rs6671364, rs17461259, rs472188, and rs535620) attained nominally significant P-values in both the genotypic (0.002, 0.02, 0.03, and 0.05, respectively) and allelic (0.001, 0.006, 0.03, and 0.02, respectively) association tests for the combined sample, and 2 additional markers (rs481047and rs1160751) displayed significance for the genotype (P-values: 0.03 and 0.04). Several haplotypes, that all included at least one of the four SNPs implicated by the single marker analysis, remained significant after adjustment for multiple testing using permutations with 10,000 shuffles. In addition we observed an association for two of the four significant GRIK3 markers (rs472188 and rs535620) to scores for negative symptoms on the PANSS scale. The present results, although not robust, support the importance of more extensive investigations of GRIK3, given its potential role in mediating risk for schizophrenia.

The interleukin-10 gene promoter polymorphism -1087AG does not correlate with clinical outcome in non-Hodgkin's lymphoma

The Interleukin 10 (IL-10) gene is highly polymorphic, and the IL-10(-1087AG) (rs1800896) gene variation is the only so far studied intensively in association with certain diseases. Conflicting data have been published about an association of IL-10(-1087AG) gene variation with lower rates of complete remission and lower overall survival (OS) in patients with diffuse large B-cell lymphoma. To further investigate this in malignant lymphoma, we established the IL-10 genotypes in patients from the NHL-B1/ B2 studies from the German High-Grade Non-Hodgkin's Lymphoma Study Group. In our study, allele frequencies of lymphoma patients are comparable as in healthy controls. No increase of IL-10(-1087G) alleles was found. In addition we did not find any difference in OS or event-free survival between patients with IL-10(-1087AA) and the other genotypes. Comparable results were obtained for the IL-10 loci at -3538 (A/T), -1354 (A/G), -824 (C/T) and -597 (A/C) (rs1800890, rs1800893, rs1800871 and rs1800872).

Hernienchirurgie: Wachstumsverhalten humaner Fibroblasten auf alloplastischen Kunststoffnetzen

BACKGROUND

The biocompatibility of meshes in hernia surgery seems to be influenced markedly by the amount of the selected material and its structure. Fibroblasts play a major key role during the process of mesh incorporation. This study was performed to investigate differences in cell morphology and proliferation of human fibroblasts cultured on different polypropylene meshes.

METHODS

In the present in vitro study the cellular response of human fibroblasts was investigated by scanning electron microscopy (SEM), comparing three different polypropylene meshes: a newly constructed low-weight and microporous mesh (NK1), a low-weight and macroporous mesh with absorbable polyglactin filaments (Vypro), and a heavy-weight and microporous mesh (BiomeshP1). Human fibroblasts (1,5.10(5) cells) were incubated with the meshes (each 12 mm(2)) for 6 hours, 5 days, 2, 4, 6, and 12 weeks. Computer-assisted morphometry of the fibroblast/mesh surface ratio served to reflect the biological cell response.

RESULTS

The Vypro mesh showed the significantly highest fibroblast density during the first 6 weeks, but cell growth was nearly exclusively limited to the polyglactin filaments. At 3 months, after reabsorption of the polyglactin, the fibroblast-coated polypropylene mesh surface was only 50% compared to NK1 and BiomeshP1. The morphologic aspect of the fibroblasts on the BiomeshP1 mesh was much more degenerative and unphysiological, compared to NK1 and Vypro, with isolated, single cells instead of a broad, connective growth. The BiomeshP1 showed a significantly higher fibroblast proliferation around the nodes of the mesh compared to the straight filaments. On the NK1 mesh fibroblasts exclusively proliferated on the filaments but not on the pressed mesh surface.

CONCLUSIONS

The polymer surface and structure appears to be of major importance for the biocompatibility of meshes: human fibroblasts preferably grow on low-weight meshes, thin filaments, and mesh nodes. Heavy-weight meshes induce degenerative cell reactions. Polyglactin seems to further improve cell proliferation whereas a pressed mesh surface without pores hinders fibroblast growth.

Combined analysis of ZAP-70 and CD38 expression as a predictor of disease progression in B-cell chronic lymphocytic leukemia

Prognostic predictions in B-cell chronic lymphocytic leukemia (B-CLL) at early clinical stage are based on biological disease parameters, such as ZAP-70 and CD38 protein levels, genomic aberrations as well as immunoglobulin variable heavy chain gene (IgV(H)) mutation status. In the current study, ZAP-70 and CD38 expressions were examined by flow cytometry in 252 patients with B-CLL. Cytoplasmic ZAP-70 expression in more than 20% (ZAP-70(+)) and surface CD38 expression on more than 30% (CD38(+)) of B-CLL cells were associated with an unfavorable clinical course. The levels of ZAP-70 and CD38 did not change over time in the majority of patients where sequential samples were available for analysis. Combined analysis of ZAP-70 and CD38 yielded discordant results in 73 patients (29.0%), whereas 120 patients (47.6%) were concordantly negative and 59 patients (23.4%) were concordantly positive for ZAP-70 and CD38 expression. Median treatment-free survival times in patients whose leukemic cells were ZAP-70(+)CD38(+) was 30 months as compared to 130 months in patients with a ZAP-70(-)CD38(-) status. In patients with discordant ZAP-70/CD38 results, the median treatment-free survival time was 43 months. Thus, ZAP-70 and CD38 expression analyses provided complementary prognostic information identifying three patient subgroups with good, intermediate and poor prognosis. Over-representation of high-risk genomic aberrations such as 17p deletion or 11q deletion and distribution of the IgV(H) mutation status in B-CLL discordant for ZAP-70/CD38 pointed toward a distinct biologic background of the observed disease subgroups. This finding was also supported by microarray-based gene expression profiling in a subset of 35 patients. The expression of 37 genes differed significantly between the three groups defined by their expression of ZAP-70 and CD38, including genes that are involved in regulation of cell survival and chemotherapy resistance.

Prognosis factors in incisional hernia surgery: 25�years of experience

BACKGROUND

Incisional hernia underwent a change from conventional techniques to mesh implantation. The relevance of different factors, like operative technique, mesh material, and patient-related parameters concerning the outcome following mesh repair, are still under debate.

METHODS

In a comparative retrospective study of 421 incisional hernia operations on 348 patients, we investigated 241 Mayo procedures and 180 mesh repairs over a 25-year period. In addition to the quality of life following mesh implantation, the prognostic relevance of demographic, preoperative and intraoperative parameters, surgical technique, mesh material, and the surgeon's experience were analysed, both in a univariate and multivariate manner.

RESULTS

With a mean follow-up of 9.7+/-8.8 years, the total recurrence rate following Mayo overlap was 37%, in contrast to 15% after mesh implantation (P=0.001). Mesh size was the only significant prognostic factor concerning quality of life following mesh implantation, and 86% of the patients with mesh repair were satisfied. The complication rate was determined significantly by patients' risk factors, size of hernia, operative technique, and the surgeon's experience, whereas the rate of recurrences was significantly influenced by the parameters obesity (BMI>25), size of hernia, and surgical experience. The recurrence rate decreased significantly with surgeon's experience-a minimum of 16 mesh repairs led to a recurrence rate of less than 10%.

CONCLUSIONS

Only the mesh repair revealed acceptable recurrence rates with high patient comfort. From a surgical point of view, the most important prognostic factor following mesh repair is the surgeon's experience.

Survival probabilities and hazard functions of malignant melanoma in Germany 1972-1996, an analysis of 10433 patients. Evolution of gender differences and malignancy

The evaluation of the impact of prevention activities on the course of survival in conjunction with the individual hazard rate of dying is described using data from a follow-up study of 10433 melanoma patients during three observation periods (1972-1980, 1981-1988, 1989-1996). Kaplan-Meier survival curves combined with hazard functions were calculated. At all observation periods, survival of men was lower compared with women and their maximum dying risk was earlier (70 versus 100 months after removal of the primary tumour). In 1989-1996, differences in the survival rates were approximately halved compared with those for 1972-1980 or 1981-1988, respectively. This improvement was predominantly seen in young men. There was a lower survival rate of men compared with women with identical thickness categories. The maximum dying risk for those men with tumours >4 mm peaked at approximately 60 months, the other thickness categories showing a lower and later maximum; in women, the maximum dying risk for tumours >4 mm was also seen at approximately 60 months, but less pronounced. Over time, the influence of Breslow thickness on the survival rates remained constant in women; in men, with the exception of thick tumours, there was a trend towards a better survival. Melanoma awareness campaigns conducted in Germany since the late 1980s have resulted in a trend towards a remarkable increase of thin tumours in recent years, whereas the number of new cases with thick tumours has remained constant.

[Mortality of invasive malignant cutaneous melanoma. A review with special consideration of gender distribution]

BACKGROUND AND OBJECTIVE

The final goals of malignant melanoma prevention are lowering incidence and mortality. We assessed the parameter "survival" for both men and women as the beginning point for future gender-directed prevention campaigns. We compared the periods 1972-1980, 1981-1988, 1989-1996, and determined the influence of age and of Breslow' tumor thickness on survival.

PATIENTS/METHODS

We had sufficient follow-up on 10.433 patients. We calculated survival curves according to Kaplan-Meier and defined differences by the logrank test.

RESULTS

At all periods of time, survival of women was higher compared with men, but with no impressive changes over time. This was especially true for younger men. The most important prognostic factor was the Breslow tumor thickness. Within all periods of time, its median was higher in men. A trend downwards for both genders could be observed with higher influence on survival in men.

CONCLUSIONS

Our findings justify melanoma prevention campaigns addressed to men. Evaluation of such campaigns has to take into account an already existing upwards trend for male survival, which exceeds that of female survival.