Perioperative or only adjuvant gemcitabine plus nab-paclitaxel for resectable pancreatic cancer (NEONAX)-a randomized phase II trial of the AIO pancreatic cancer group.

BACKGROUND: Data on perioperative chemotherapy in resectable pancreatic ductal adenocarcinoma (rPDAC) are limited. NEONAX examined perioperative or adjuvant chemotherapy with gemcitabine plus nab-paclitaxel in rPDAC (National Comprehensive Cancer Network criteria). PATIENTS AND METHODS: NEONAX is a prospective, randomized phase II trial with two independent experimental arms. One hundred twenty-seven rPDAC patients in 22 German centers were randomized 1 : 1 to perioperative (two pre-operative and four post-operative cycles, arm A) or adjuvant (six cycles, arm B) gemcitabine (1000 mg/m2) and nab-paclitaxel (125 mg/m2) on days 1, 8 and 15 of a 28-day cycle. RESULTS: The primary endpoint was disease-free survival (DFS) at 18 months in the modified intention-to-treat (ITT) population [R0/R1-resected patients who started neoadjuvant chemotherapy (CTX) (A) or adjuvant CTX (B)]. The pre-defined DFS rate of 55% at 18 months was not reached in both arms [A: 33.3% (95% confidence interval [CI] 18.5% to 48.1%), B: 41.4% (95% CI 20.7% to 62.0%)]. Ninety percent of patients in arm A completed neoadjuvant treatment, and 42% of patients in arm B started adjuvant chemotherapy. R0 resection rate was 88% (arm A) and 67% (arm B), respectively. Median overall survival (mOS) (ITT population) as a secondary endpoint was 25.5 months (95% CI 19.7-29.7 months) in arm A and 16.7 months (95% CI 11.6-22.2 months) in the upfront surgery arm. This difference corresponds to a median DFS (mDFS) (ITT) of 11.5 months (95% CI 8.8-14.5 months) in arm A and 5.9 months (95% CI 3.6-11.5 months) in arm B. Treatment was safe and well tolerable in both arms. CONCLUSIONS: The primary endpoint, DFS rate of 55% at 18 months (mITT population), was not reached in either arm of the trial and numerically favored the upfront surgery arm B. mOS (ITT population), a secondary endpoint, numerically favored the neoadjuvant arm A [25.5 months (95% CI 19.7-29.7months); arm B 16.7 months (95% CI 11.6-22.2 months)]. There was a difference in chemotherapy exposure with 90% of patients in arm A completing pre-operative chemotherapy and 58% of patients starting adjuvant chemotherapy in arm B. Neoadjuvant/perioperative treatment is a novel option for patients with resectable PDAC. However, the optimal treatment regimen has yet to be defined. The trial is registered with ClinicalTrials.gov (NCT02047513) and the European Clinical Trials Database (EudraCT 2013-005559-34).

Model of wound healing for esophagogastric anastomoses in rats.

BACKGROUND: Anastomotic leakage after esophageal surgery is a significant cause of morbidity and mortality. Postoperative leakage of esophagogastric anastomosis has been reported in 2-30% of surgical patient, resulting in an increased need for reoperation and a high risk of subsequent esophageal stricture formation and fistula. So far, experimental investigations on major factors influencing the healing of esophageal anastomoses, e.g. neovascularization and collagen deposition, have been hindered by the lack of a functional rodent model. METHODS: We developed a novel technique of gastric tube formation followed by end-to-end esophagogastric anastomosis in a rat model. Standardized anastomoses were carried out in 18 Brown-Norway rats and normal esophagogastric healing was studied by measuring anastomotic breaking strength 5 days after surgery. RESULTS: Five animals showed an insufficiency of the esophagogastric anastomosis as determined by anastomotic leakage testing. Normal anastomotic healing was found in 10 animals. The anastomotic breaking strength was 1.93 ± 0.45 N. CONCLUSION: The rat model for performing esophagogastric anastomoses after gastric tube formation may serve as a functional and useful model in future research studies on microvascular and molecular processes of anastomotic healing.

[With the scalpel against the immune system: HIV infection complicated by an unclear colitis]. / Mit dem Skalpell gegen das Immunsystem: eine unklare Kolitis bei HIV-Infektion.

A 35-year-old Kenian lady with advanced immunodeficiency due to HIV infection started on an antiretroviral therapy. Five months later, a severe colitis was diagnosed, however, no causal pathogen could be found. In order to avoid imminent perforation, a hemicolectomy became necessary, and immediately the symptoms and inflammation markers normalized rapidly. M. tuberculosis could be proven in culture in a draining abdominal lymph node. We assume that the severe inflammation was caused by an immune restoration inflammatory syndrome (IRIS). Essentials in diagnosis, pathogenesis and therapy of IRIS are discussed.

Etiopathological aspects of achalasia: lessons learned with Hirschsprung's disease.

The etiology of primary esophageal achalasia is largely unknown. There is increasing evidence that genetic alterations might play an important but underestimated role. Current knowledge of the genetic base of Hirschsprung's disease in contrast is far more detailed. The two enteric neuropathies have several clinical features in common. This association may also exist on a cellular and molecular level. The aim of this review is to enlighten those etiopathogenetic concepts of Hirschsprung's disease that seem to be useful in uncovering the pathological processes causing achalasia. Three aspects are looked at: (i) the genetic base of Hirschsprung's disease, particularly its major susceptibility gene rearranged during transfection and its potential reference to achalasia; (ii) the altered motor functions in both conditions with loss of inhibitory innervation and interstitial cell pathology; and (iii) the involvement of these motility disorders in genetic syndromes.

SDF1ß expression in renal cell carcinoma correlates with grading and infiltration by CD8+ T-cells.

For several tumor entities, a significant correlation between the chemokine stromal cell-derived factor 1 (SDF1) and its receptor C-X-C chemokine receptor type 4 (CXCR4), metastasis and tumor proliferation, as well as prognosis, has been described. In this study, a series of 105 renal cell carcinoma patients were analyzed in terms of expression of SDF1α and SDF1ß and infiltration by CD4+ and CD8+ T-cells and the data correlated with TNM category, grading and survival. While the splice variant SDF1α had no impact on tumor grading, T-cell invasion or overall survival, expression of SDF1ß showed a significant correlation with tumor grading and also suggested a correlation with metastasis, as well as CD8+ T-cell invasion. These results indicate a potential T-cell-mediated antitumor response induced by SDF1ß up-regulation. Therefore targeting the SDF1ß-CXCR4 signaling pathway may be a promising means for new therapeutic strategies in advanced tumor stages.

[Detection of hepatic micrometastases in the context of adjuvant chemotherapy and surgery for hepatic metastases]. / Nachweis hepatischer Mikrometastasen.

Colorectal cancer is one of the three most frequent malignancies in humans. Survival is mainly determined by local recurrence, lymphatic and hematogenous dissemination. Primary liver resection for metastases is possible in ~20-25% of patients with hepatic metastases and results in a 50% recurrence rate within 23 months. The five-year survival without treatment in patients with UICC stage IV is only 5%, the mean survival 6-9 months. As a result of promising developments in chemotherapy and targeted therapies in the last decade, the mean survival rate has significantly improved to over more than two years. Furthermore, the use of polychemotherapy in combination with anti-angiogenic and anti-proliferative biologicals has resulted in a significant increase of secondary resectability of liver metastases. Despite of a R0-resection (i.e. resection with clear margins) of liver metastases, only 30% of patients remain free of recurrence in the long-term. Prognostic scores are used for optimal patient selection, e.g. the Fong-Score. Resection is often limited by a high number of recurrences: intrahepatic micrometastases and disseminated tumor cells (DTC) are suspected as the cause of their development. In this connection the load of disseminated tumor cells correlates significantly with the survival and recurrence rate after resection. These micrometastases are targets in current adjuvant treatment studies (e.g. MT 201) by using anti-EpCam antibodies. The detection of DTC can supplement the previously used scores and represents the indication for an adjuvant antibody-based treatment (e.g. anti-EpCam) in the context of clinical trials.

Prediction model of lymph node metastasis in superficial esophageal adenocarcinoma and squamous cell cancer including D2-40 immunostaining.

BACKGROUND: It was the aim of our study to establish a model for prediction of lymph node metastases in superficial esophageal cancer. METHODS: We analyzed the clinical and histopathological data of 50 consecutive patients with pT1-esophageal cancer who underwent oncological resection. Submucosal carcinomas (pT1b) were classified according to sm levels 1-3. D2-40 immunostaining was investigated using the ABC technique. In a first step, we performed univariate analysis (One-way ANOVA: Sigma restricted parameterization; test of SS whole vs. SS predicted) to test the predictive value of the following categorical parameters for lymph node status (positive/negative): sex, histologic tumor type, localization, surgical technique (transhiatal/transthoracic), grading, pT1-subclassification (pT1a, pT1b sm 1-3), pL-, pV-status, and D2-40 labeling. Simple regression was applied for the following continuous predictors: age and tumor size. All significant variables of univariate analysis were included in the multivariate analysis. For this purpose, we used the General Liner Models's analysis (forward stepwise). In a third step, the Kruskal-Wallis test with post hoc comparisons was intended to define the cut-off value of parameters tested. RESULTS: Only the following variables gained statistical significance in univariate analysis: sex, histological tumor type, grading, pT1-subclassification, lymphatic infiltration, microvascular infiltration, D2-40 immunostaining, and tumor size (P < 0.05). Variables reaching significance in multivariate analysis were tumor size (P = 0.017) and pV-status (P = 0.037). In the Kruskal-Wallis test with post hoc comparisons, the cut-off value of tumor size was 2 cm (model P = 0.002) and between the categories (P < 0.05). CONCLUSIONS: Lymph node positivity and lymphatic vessel infiltration did not linearly increase with sm tumor infiltration depth. The risk category of lymph node involvement in superficial esophageal cancer exists according to our prediction model on the basis of tumor size of >2 cm and microvascular infiltration. The hitherto common sm levels 1-3 classification of submucosal cancers appears to display a lesser impact than previously assumed with regard to prediction of potential lymph node metastases and consequently the indication for endoscopic or surgical therapy.

[Immunotherapy of colorectal cancer--overview and perspectives]. / Immuntherapie des Kolorektalkarzinoms--aktueller Stand und Perspektiven.

The specific immunotherapy of colorectal cancer initially revealed promising results. However, a significant clinical benefit for patients has still to be proven in phase III trails. In order to compare the different clinical approaches and early phase I - II studies, there is an urgent need for the establishment and acceptance of new standardized diagnostic tools for detecting and quantifying induced and clinical relevant immune responses in patients. Whether or not subgroups with a certain genetic background, such as specific HLA alleles, reveal a better benefit from tumour vaccinations needs to be further analysed. Currently, only two specific antibodies, targeting membraneous receptors or their ligands, such as EGF or VEGF, have been approved by diverse national drug authorities. The question as to whether these antibodies also induce an antibody-dependent cellular toxicity (ADCC) is currently being analysed.

Dissemination of hepatocellular carcinoma is mediated via chemokine receptor CXCR4.

In different tumour entities, expression of the chemokine receptor 4 (CXCR4) has been linked to tumour dissemination and poor prognosis. Therefore, we evaluated, if the expression of CXCR4 exerts similar effects in human hepatocellular carcinoma (HCC). Expression analysis and functional assays were performed in vitro to elucidate the impact of CXCL12 on human hepatoma cells lines. In addition, expression of CXCR4 was evaluated in 39 patients with HCC semiquantitatively and correlated with both, tumour and patients characteristics. Human HCC and hepatoma cell lines displayed variable intensities of CXCR4 expression. Loss of p53 function did not impact on CXCR4 expression. Exposure to CXCL12 mediated a perinuclear translocation of CXCR4 in Huh7/Hep3B cells and increased the invasive potential of Huh7 cells. In HCC patients, CXCR4 expression significantly correlated with progressed local tumours (T-status; P=0.006), lymphatic metastasis (N-status; P=0.005) and distant dissemination (M-status; P=0.009), as well as with a decreased 3-year-survival rate (P=0.01). In summary, strong expression of CXCR4 is significantly associated with progressed hepatocellular cancer.

Expression of Hugl-1 is strongly reduced in malignant melanoma.

The human gene Hugl-1 (Llgl/Lgl1) has significant homology to the Drosophila tumor suppressor gene lethal(2)giant larvae (lgl). The lgl gene codes for a cortical cytoskeleton protein, Lgl, that is involved in maintaining cell polarity and epithelial integrity. We speculate that Hugl-1 might play a role in epithelial-mesenchymal transition (EMT) and that loss of Hugl-1 expression plays a role in the development or progression of malignant melanoma. Thus, we evaluated melanoma cell lines and tissue samples of malignant melanoma for loss of Hugl-1 transcription. We found that Hugl-1 was downregulated or lost in all cell lines and in most of the tumor samples analysed, and that these losses were associated with advanced stage of the disease. Reduced Hugl-1 expression occurred as early as in primary tumors detected by both immunohistochemical and reverse transcription-polymerase chain reaction (RT-PCR) analysis. Functional assays with stable Hugl-1-transfected cell lines revealed that Hugl-1 expression increased cell adhesion and decreased cell migration. Further, downregulation of MMP2 and MMP14 (MT1-MMP) and re-expression of E-cadherin was found in the Hugl-1-expressing cell clones supporting a role of Hugl-1 in EMT. Our studies thus indicate that loss of Hugl-1 expression contributes to melanoma progression.

Extended staging results from the detection of isolated tumor cells in the liver of colorectal cancer patients.

Liver metastasis, as well as local recurrence, are delineating factors of postoperative survival in patients suffering from colorectal cancer. We set up a PCR-RFLP assay to detect K-ras mutated cells in liver tissue as an indicator of possible isolated tumor cells (ITC) or micro-metastasis at the time of surgery. Sixty-four patients with K-ras codons 12 or 13 mutated colorectal cancer were clinically diagnosed for liver metastasis, as well as by PCR-RFLP assay of DNA from liver biopsies. Macro-metastasis was observed in the liver of 7 patients (11%), with no additional evidence of ITC. Likewise, in the liver of 14 patients (22%) only ITC, but no macro-metastasis was detected. In another 7 patients (11%) there was both, ITC and macro-metastasis. No macro-metastasis or ITC were found in 36 patients (56%). Thus, the PCR-RFLP assay added 14 cases (22%) with potential liver-metastasis to the 14 cases (22%) detected by clinical diagnostic means. T and N status were related to the refined detection and extended classification of liver involvement. We conclude that clinical and PCR-RFLP methods supplement each other and can increase the detection of cases with liver involvement, if applied together.

Sensitive detection of K-ras mutations augments diagnosis of colorectal cancer metastases in the liver.

Postoperative survival of colorectal cancer patients is often delineated by metastases spreading to the liver. Current clinical diagnostic procedures are unable to discover micrometastases in this organ. Our aim was to develop a diagnostic tool for detecting micrometastases that are present at the time of surgery. Therefore, a PCR-RFLP assay was set up tracking point mutations of the K-ras oncogene at codons 12 and 13, based on mismatch primers and restriction enzymes BstXI and XcmI. The detection limit of this assay was one mutant in one million wild-type cells. One hundred forty-two patients with colorectal carcinoma were screened for these mutations in tissue samples from their tumor, proximally adjacent mucosa, and liver. Of these, 67 patients (46%) were positive for a K-ras mutation, of which 58 had codon 12 and 9 had codon 13 mutations. No patient without a K-ras-positive tumor showed a mutation in mucosa, but 11 patients with a K-ras-positive tumor (11 of 58; 19%) were found to bear a K-ras mutation in their mucosa, and in 21 patients (21 of 64; 33%), a K-ras mutation was detected in liver tissue. Sequencing of all mutated samples revealed a 92% confirmation of PCR-RFLP results. In summary, the assay is a useful tool for detecting K-ras codon 12 and 13 mutations and allows early proof of molecular determinants of liver metastases. Such knowledge will improve the staging of colorectal cancer patients and could beneficially influence their prognosis if followed by an effective therapy.

Sampling technique influences the detection of K-ras mutations in normal appearing mucosa of colorectal cancer patients.

Based on three colorectal cancer cell lines with specified K-ras status, a sensitive PCR-RFLP assay was established detecting one K-ras mutant among 106 wild-type cells. Using this assay for tissues of 124 colorectal cancer patients, 59 tumor (46%) and 11 mucosa samples (9%) were found to harbor a K-ras mutation. When using the same scalpel for collecting tumor and mucosa tissues (group A), 18% of the patients had a matching K-ras mutation in both tissues, but this coincidence was seen in 3% of patients only, when separate scalpels were used (group B). Thus we conclude that the sampling technique used for collecting specimens is a major contributor to the detection of K-ras mutations in normal appearing mucosa when a highly sensitive detection technique is used.