Multicenter phase II trial to investigate safety and efficacy of gemcitabine combined with cetuximab as adjuvant therapy in pancreatic cancer (ATIP)

BACKGROUND

To investigate whether addition of cetuximab to standard adjuvant chemotherapy with gemcitabine improves outcome in pancreatic cancer, specifically whether the rate of disease-free survival (DFS) at 18 months (primary end point) exceeds the previously reported 35% of gemcitabine alone.

PATIENTS AND METHODS

Prospective, open-label, multicenter, nonrandomized phase II study in 76 patients with R0- or R1-resected ductal adenocarcinoma of the pancreas included between October 2006 and November 2008. Gemcitabine and cetuximab were administered for 24 weeks. Secondary end points included overall survival (OS) and toxic effect.

RESULTS

Seventy-three patients received cetuximab. Median DFS was 10.0 [95% confidence interval (CI) 8.9-13.6] months and the DFS rate at month 18 of 27.1% (16.7%-37.6%) was inferior to 35%. Median OS was 22.4 (18.2-27.9) months. Subgroup analyses revealed a nonsignificant increase in DFS for patients with versus without skin toxic effect ≥ grade 2 (median 14.7 versus 8.3 months, P = 0.073) and wild-type versus mutated K-Ras (median 11.5 versus 9.3 months, P = 0.57). Grade 3/4 toxic effects included neutropenia (11.0%), thrombopenia (7%), skin toxic effect (7%) and allergic reactions (7%).

CONCLUSION

Addition of cetuximab to adjuvant gemcitabine does not seem to improve DFS or OS of unstratified pancreatic cancer patients. Trends for improved DFS in patients with wild-type K-Ras and skin toxic effect remain to be confirmed.

[Reflux-associated nutcracker oesophagus in a 49-year-old patient with non-cardiac chest pain (NCCP)]

A 49-year-old woman was admitted to our department because of intermittent left-sided chest pain for the past 2 years. The patient reported an increasing frequency and duration of the symptoms which were independent from food intake, medication or physical exercises. A cardiac cause of the chest pain was excluded before admittance to our hospital. The initially performed upper endoscopy revealed a small oesophageal hiatal hernia but no signs of acute or chronic inflammation. Basal oesophageal manometry and pH monitoring confirmed the presence of a nutcracker oesophagus, defined by high-amplitude contractions of the distal oesophagus, in combination with a gastro-oesophageal reflux disease. The patient was treated with high-dose pantoprazole for 8 weeks before re-examination. Interestingly, the symptoms completely disappeared upon medication and the relief of the chest pain was accompanied by normalisation of the nutcracker oesophagus pattern. Thus, our observation provides evidence for a causative role of acid reflux in the pathophysiology of the nutcracker oesophagus and, in addition, suggests that effective acid suppression might be a useful therapeutic tool to deal with this painful motility disorder of the oesophagus.

Use of DNA arrays/microarrays in pancreatic research

In recent years, enormous technical advances in experimental protocols as well as robotic and bioinformatic techniques have allowed DNA array/microarray technology to emerge as the leading technology in the field of functional, disease-related genome analysis. Multiple applications exist for DNA arrays/microarrays including comparative genomic analysis to identify chromosomal imbalances (Matrix-CGH), the study of mutations and genetic polymorphisms, and the study of gene expression (expression profiling). Expression profiling is the most widely used application of DNA array/microarray technology and allows to measure gene expression of thousands of genes simultaneously. The present review describes the basic principles of expression profiling analyses and outlines some applications in pancreatic cancer research.

Biglycan is overexpressed in pancreatic cancer and induces G1-arrest in pancreatic cancer cell lines

BACKGROUND & AIMS

Biglycan (PG-I), a component of the extracellular matrix (ECM), is overexpressed in pancreatic cancer. To determine possible matrix-tumor interactions, we investigated the effects of PG-I on pancreatic cancer.

METHODS

PG-I expression in cell lines and tissue samples was examined by Northern blot and immunofluorescence. The effect of PG-I on proliferation was determined by measuring activity of Ras, ERK, Rb, [(3)H]-thymidine incorporation, and cell cycle analysis. Expression of cyclin A, B1, D1, E1, G1, PCNA, p21, and p27 was analyzed by Northern and Western blots.

RESULTS

PG-I was overexpressed in the ECM of pancreatic cancer samples compared with normal pancreas or chronic pancreatitis tissues. Addition of transforming growth factor (TGF)-beta induced PG-I expression in HFL and HFFF2 fibroblasts as well as in the pancreatic cancer cell line PANC-1. PG-I inhibited growth of both TGF-beta-responsive and TGF-beta-unresponsive pancreatic cancer cells by inducing G1-arrest, which is accompanied by an increase of p27 and reduction of cyclin A and proliferating cell nuclear antigen. Furthermore, endogenous Ras and ERK activation was partly reduced by PG-I in vitro.

CONCLUSIONS

The ECM protein PG-I inhibits growth by arresting pancreatic cancer cells in G1 and may be part of a host defense mechanism aimed at slowing down pancreatic tumor progression.

Influence of clarithromycin dosage on pantoprazole combined triple therapy for eradication of Helicobacter pylori

BACKGROUND

Low-dose clarithromycin (250 mg b.d.) in combination with omeprazole and metronidazole has been recommended for the eradication of Helicobacter pylori. Whether the substitution of omeprazole by pantoprazole requires adjustment of the clarithromycin dose is not known.

AIM

To directly compare the efficacy and tolerability of two different dosages of clarithromycin in combination with pantoprazole and metronidazole.

METHODS

One hundred and sixty-three patients with endoscopically confirmed gastritis, gastric or duodenal ulcers and positive H. pylori findings in the rapid urease test were randomized and treated for 7 days with pantoprazole (40 mg b.d.). metronidazole (500 mg b.d.) and clarithromycin using either a regimen of 500 mg b.d. (group PMC 500) or 250 mg b.d. (group PMC 250). Eradication success was determined no less than 4 weeks after concluding therapy using the 13C-urea breath test.

RESULTS

One-hundred and thirty-nine patients completed the study. Based on a per protocol analysis. successful eradication was documented in 63/70 patients (90.0%) in group PMC 500 and in 62/69 patients (89.9%) in group PMC 250. Based on the intention-to-treat analysis, eradication rates were 78.8% (group PMC 500) and 75.6% (group PMC 250). The incidence of adverse effects was significantly higher in patients receiving PMC 500 (50.0%) than in those receiving PMC 250 (25.4%).

CONCLUSIONS

Triple therapy with pantoprazole, metronidazole and clarithromycin provides an efficient eradication regimen for H. pylori infection. A low dose of clarithromycin is equal to a higher dose in therapeutic efficacy and it offers the advantage of improved tolerance and lower cost.