Data suggest that specific chromosomal alterations in clear cell renal cell carcinoma can be used to predict metastasis and cancer specific survival in patients with clear cell renal cell carcinoma. It seems possible to design a combined fluorescence in situ hybridization assay based on these genetic targets for outcome prediction, which can be used for routine diagnostics.

An experimental in vitro study involving ten hand-sutured, ten biofragmentable anastomotic ring (BAR) and ten stapled anastomoses was conducted to compare current anastomotic techniques on the basis of early bursting pressure. The 30 fresh human colon segments used in the study were harvested from patients who had undergone elective oncologic resection. Following the construction of in vitro anastomoses, the pressure required to burst these specimens was measured. The results showed no significant differences among the three techniques. Since hand-sutured anastomoses proved to be as effective and reliable as the other methods and can offer the advantage of cost savings, they should remain standard procedure in colorectal surgery.

Purpose In mCRC, disease dynamics may play a critical role in the understanding of long-term outcome. We evaluated depth of response (DpR), time to DpR, and post-DpR survival as relevant endpoints. Methods We analyzed DpR by central review of computer tomography images (change from baseline to smallest tumor diameter), early tumor shrinkage (≥ 20% reduction in tumor diameter at first reassessment), time to DpR (study randomization to DpR-image), post-DpR progression-free survival (pPFS = DpR-image to tumor progression or death), and post-DpR overall survival (pOS = DpR-image to death) with special focus on BRAF status in 66 patients and primary tumor site in 86 patients treated within the VOLFI-trial, respectively. Results BRAF wild-type (BRAF-WT) compared to BRAF mutant (BRAF-MT) patients had greater DpR (− 57.6% vs. − 40.8%, p = 0.013) with a comparable time to DpR [4.0 (95% CI 3.1-4.4) vs. 3.9 (95% CI 2.5-5.5) months; p = 0.8852]. pPFS was 6.5 (95% CI 4.9-8.0) versus 2.6 (95% CI 1.2-4.0) months in favor of BRAF-WT patients (HR 0.24 (95% CI 0.11-0.53); p < 0.001). This transferred into a significant difference in pOS [33.6 (95% CI 26.0-41.3) vs. 5.4 (95% CI 5.0-5.9) months; HR 0.27 (95% CI 0.13-0.55); p < 0.001]. Similar observations were made for patients stratified for primary tumor site. Conclusions BRAF-MT patients derive a less profound treatment response compared to BRAF-WT patients. The difference in outcome according to BRAF status is evident after achievement of DpR with BRAF-MT patients hardly deriving any further disease control beyond DpR. Our observations hint towards an aggressive tumor evolution in BRAF-MT tumors, which may already be molecularly detectable at the time of DpR.

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Introduction: Clear cell renal cell carcinoma (ccRCC) is the most frequently encountered renal malignancy with a high metastatic potential and the prognosis of patients in this subgroup is very poor. Prognostic parameters which can be used for an individual prognostic evaluation are still not available, So the aim of our study was high resolution screening of genomic imbalances of metastasized and non-metastasized primary ccRCC by array CGH in order to identify regions of DNA copy number changes significantly associated with metastasis and clinical outcome of patients. Methods: We conducted genome-wide copy number profiles in 56 primary ccRCC including 32 metastasized and 24 non-metastasized tumours by array CGH with a median resolution of 2Mbp. The median follow up of the patients was 47 months. Results: Array CGH identified 6 recurrent chromosomal aberrations: gains of 1q21.3, 12q13.11, 12q13.2 and 20q11.21q13.2 and losses of 8p11.23p12 and 9p21.3p24.1, which were significantly associated with metastasis occurrence. In multivariate analysis including these aberrations gains of 1q21.3 and of 20q11.21q13.2 and loss of 9p21.3p24.1 attained as independent predictors for metastasis in our cohort with 81.5% sensitivity and 95.8% specificity of 81.5% and 95.8%, respectively. Kaplan-Meier survival analysis showed that gains on chromosomes 7, 12, 16 and 20q and losses on chromosome 9 have a significant correlation with disease specific survival. Multivariate Cox-regression analysis revealed gains of 7q36.3 and of 20q11.21q13.2 and a loss of 9p21.3p24.1 as independent prognostic factors for patients' outcome of patients. Conclusions: Our data suggest that specific common copy number alterations in ccRCC could serve as independent predictors for metastasis occurrence and cancer specific survival in patients with ccRCC. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2246.

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Introduction: Treatment of acute myeloid leukemia (AML) in elderly patients remains challenging. Low-dose DNA hypomethylating agents are a therapeutic option in myelodysplastic syndromes and AML. However, the mechanism of action of hypomethylating agents and the role of induction of DNA hypomethylation in the clinical response is still unclear. To unravel the in vivoeffects of sequential cycles of decitabine, we set out to characterize methylomes of leukemic blasts, T cells (presumably not part of the malignant clone) and granulocytes before and during treatment of AML patients enrolled in the randomized phase II DECIDER clinical trial (NCT00867672). We developed a statistical model for longitudinal data analysis to identify the strongest hypomethylation response. Methods: Peripheral blood mononuclear cells (PBMC) from AML patients were collected before and during therapy (i.v. 20 mg/m2 decitabine for 5 days, with or without subsequent oral drug add-on). Leukemic blasts and T-cells were isolated using automatic magnetic sorting of cells (autoMACS) labelled with anti-human CD34, CD117 and CD3 MACS microbeads (Miltenyi Biotec), respectively. Granulocytes were isolated using dextran sedimentation. Cell type specific genome-wide DNA methylation profiles were obtained using Infinium Human Methylation 450 BeadChip arrays. Data were analyzed using R packages RnBeads applying beta mixture quantile dilation for normalization (Teschendorff et al. Bioinformatics, 29:189–196, 2013) and a modified version of NHMMfdr for multiple testing. Results: Peripheral blood blasts (median purity: 92%) were isolated from 20 patients, and T cells (median purity: 94%) from 26 patients before treatment and on days 4 and/or 8 and 15 of treatment cycle 1. From 10 patients, blasts and T cells were also collected during and/or after cycle 2. In total, until now 127 methylomes (46 blasts, 47 T cells, 34 granulocytes) were generated and used for mathematical modelling. Since the trial is still recruiting, genome-wide methylation was interpreted blinded to all clinical data including drug add-on (ATRA, valproic acid). First, the methylation dynamics of each individual CpG site described by a specified summary statistics were identified. Then, inter-probe distance and CpG annotation were incorporated to explain the dependence structure between CpG sites. In order to control the false discovery rate (FDR), we adapted a method proposed for differential DNA methylation (Kuan & Chiang, Biometrics 68: 774–783, 2012). The summary statistics for each CpG site were modelled to follow a non–homogeneous hidden Markov model. Statistical testing was validated by simulations revealing a very high discriminative power for affected CpGs even with very low methylation dynamics. Applying the model to blasts and T cells, extensive differences in the in vivomethylation changes became apparent. In blasts, 13% of CpG (59,920 CpGs of total 460,343 CpGs) showed significant DNA hypomethylation (Δβ>0.1, FDR<0.05) shared between patients by day 8, 75.8% of which (45,428 CpGs) were at least partially remethylated by day 15. Out of the 59,920 CpGs hypomethylated by day 8, 21.2% were located in promoters, 50.1% in gene bodies and 28.7% in intergenic regions. In contrast, in T cells only 2 CpGs out of 460,343 CpGs were significantly hypomethylated. This low number is partially due to the higher inter-individual variance as compared to leukemic blasts. Increases in DNA methylation across all patients were very rare, with only 38 CpGs consistently and significantly hypermethylated in blasts and none in T cells. Methylome analysis in granulocytes is currently ongoing. Conclusions: Our mathematical model revealed significant DNA hypomethylation by day 8, with striking remethylation by day 15 from start of decitabine treatment in AML blasts in vivo. Most of the hypomethylated CpGs resided in non-promoter regions. In contrast, T-cells were much less affected, which might be due to the low cell division rate and the fact that they are non-malignant cells. This model will hopefully allow determination whether the effects of decitabine are targeted or random, by including sequential samples from later treatment cycles. Unblinding of the patients' clinical data will reveal potential biomarkers of response to epigenetic therapy. Disclosures Lübbert: Ratiopharm: received study drug valproic acid, received study drug valproic acid Other; Johnson&Johnson: Honoraria, Membership on an entity's Board of Directors or advisory committees, received study drug decitabine Other.