[Multimodal treatment of pancreatic cancer]

Adenocarcinoma of the exocrine pancreas is one of the most aggressive types of solid tumor and stands at fourth position in the tumor death frequency scale due to a high mortality rate. Effective screening methods are not available and only radical surgery offers a curative option. With adjuvant chemotherapy the median survival time can be prolonged up to 23 months and approximately 25 % of patients are still alive after 5 years. Of these patients approximately 75-80 % are already in a palliative therapy situation at the time of diagnosis. In the last 5 years treatment options have been increased by the introduction of new chemotherapeutic drugs. For patients with metastasized disease median survival times of 6-12 months can currently be achieved depending on the general performance status at diagnosis but less than 5 % of these patients are still alive after 5 years. Neoadjuvant treatment strategies, radiation and immunotherapy do not play a role in evidence-based clinical practice. Despite progress in the understanding of cancer biology and new treatment options, non-resectable adenocarcinoma of the pancreas remains a disease with a very poor prognosis.

[Primary pharmacological prevention of thromboembolic events in ambulatory patients with advanced pancreatic cancer treated with chemotherapy?]

BACKGROUND AND OBJECTIVE

The indication for medical venous thrombosis prophylaxis in ambulatory cancer patients is still under discussion. To provide more data on this topic we conducted an analysis in ambulatory patients with advanced pancreatic adenocarcinoma, reflecting a patient cohort at high risk of symptomatic venous thromboembolism (sVTE).

PATIENTS AND METHODS

Data from 312 consecutively recruited patients of the CONKO-004 trial were analysed according to predefined parameters and additionally with respect to established scores. To focus on patients with highest risk of sVTE unvaried and multivariate analyses were conducted.

RESULTS

The global analyses had educed a number needed to treat (NNT) by medical thrombosis prophylaxis of 12 patients to prevent one sVTE. The modified score model did not provide further clinical benefit. However, the regression model can identify single parameters with a trend to higher risk of sVTE or higher risk of severe bleeding. Most of the parameters do not have enough power to be significant, but they can support clinical decisions.

CONCLUSION

These data suggest that medical thrombosis prophylaxis should be performed in patients with advanced pancreatic cancer at least for the initial 3 months of first line chemotherapy.

A prospective, randomized trial of chemotherapy with or without the low molecular weight heparin (LMWH) enoxaparin in patients (pts) with advanced pancreatic cancer (APC): Results of the CONKO 004 trial

LBA4506

Background: The course of pts with APC is often complicated by venous thromboembolic events (VTE). Anticoagulation therapy with LMWH may prevent VTE and is under discussion to improve overall survival (OS) in cancer. Based on our previous pilot study (Hilbig et al, Onkologie 2005;28(suppl 3)) indicating the safety and feasibility to the addition of the LMWH enoxaparin to chemotherapy in pts with APC we started the open, prospective, randomized, multicenter study to investigate the role of enoxaparin in these pts. Methods: Primary endpoint was the reduction of symptomatic VTE (sVTE) from an expected 10% to 3% within the first 12 weeks of treatment. The occurrence of sVTE (secured by an independent, blinded event review board) in 24 pts was calculated to be necessary in order to define the role of enoxaparin in decreasing the risk of VTE. Toxicity, time to progression (TTP), and OS were among the secondary endpoints of the study approved by the ethics committees of the participating centers. VTE-naive and chemotherapy-naive pts with histologically or cytologically confirmed APC were randomized to receive or not to receive additional LMWH (enoxaparin 1mg/kg once daily) starting in parallel to palliative systemic chemotherapy. Results: In January 2009 after recruitment of 312 pts the study was closed. There were 22 sVTE in 152 pts of the observation group (O) and 8 in 160 pts of the enoxaparin group (E). ITT and PP analyses demonstrated significant risk reductions from 14.5% to 5.0% (65% RRR) and 14.5% to 3.8% (74% RRR) for E, respectively. Major bleeding events were 9.9% for O and 6.3% for E (ITT; n.s.). In each group there was one tumor-related fatal hemorrhage. Preliminary data show no difference in TTP (O:19 vs. E:22 w) and OS (O:29 vs. E:31 w). Conclusions: Enoxaparin is effective and safe in the primary prevention of sVTE applied in parallel with cytotoxic chemotherapy in pts with APC. Final results on TTP and OS are pending.

No significant financial relationships to disclose.

A prospective, randomized trial of chemotherapy with or without the low molecular weight heparin (LMWH) enoxaparin in patients (pts) with advanced pancreatic cancer (APC): Results of the CONKO 004 trial

LBA4506

The full, final text of this abstract will be available in Part II of the 2009 ASCO Annual Meeting Proceedings, distributed onsite at the Meeting on May 30, 2009, and as a supplement to the June 20, 2009, issue of the Journal of Clinical Oncology.

No significant financial relationships to disclose.

Surgical results of patients after esophageal resection or extended gastrectomy for cancer of the esophagogastric junction

Precise classification of cancers of the esophagogastric junction according to Siewert may be difficult for the presence of Barrett's esophagus or hiatal hernia, which subsequently leads to a difficult choice of the surgical procedure of esophagectomy or gastrectomy. Ninety-six patients with such cancers were operated on in our department in 7 years. Twenty-nine patients (30.2%), classified as type I (group 1), underwent a transthoracic esophagectomy with gastric pull up. Sixty-seven patients (69.8%) classified as type II or III (group 2) underwent an extended gastrectomy. We compared the patients of both groups retrospectively for disease-free survival and postoperative complications. The general performance status of most patients was comparable in both groups and was assigned to the American Society of Anesthesiologists class II or III. Statistically significant differences between the groups were seen for the postoperative reintubation rate [group 1: 31.0% vs. group 2: 9.0% (P = 0.009)], median time for surgery [group 1: 6 (3.5-8.5) hours vs. group 2: 4.7 (2.2-11.5) hours (P = 0.001)], time in the intensive care unit [group 1: 6 (3-85) days vs. group 2: 3 (1-54) days (P = 0.001)], median hospitalization time [group 1: 23 (14-105) days vs. group 2: 18 (10-63) days (P = 0.018)]. No statistical difference was observed for the recurrence-free survival of 40% after 3 years (P = 0.311), the mortality rate, the morbidity rate (P = 0.108), surgical and respiratory complications, and the incidence of anastomotic leakage (P = 0.645). We conclude that in selected cases it may be possible to perform an extended gastrectomy for small type I cancers.

Capecitabine plus oxaliplatin as first-line treatment in patients with advanced biliary system adenocarcinoma: a prospective multicentre phase II trial

This prospective multicentre phase II study characterises the toxicity and activity of first-line capecitabine and oxaliplatin combination therapy (CAPOX) in advanced biliary system adenocarcinomas. Patients received oxaliplatin (130 mg m⁻², day 1) plus capecitabine (1000 mg m⁻² b.i.d., days 1–14) every 3 weeks. Patients were stratified prospectively into two groups based on location of the primary (gallbladder carcinoma (GBC) or extrahepatic cholangiocarcinoma (ECC) versus intrahepatic mass-forming type cholangiocarcinoma (ICC)). Sixty-five patients were evaluable. The response rate in 47 patients with GBC/ECC was 27% (4% complete responses), and in 23 patients (49%) stable disease (SD) was encountered. In 18 patients with ICC, we observed no objective responses, but 6 patients (33%) had SD. Median survival was 12.8 months (95% CI, 10.0–15.6) for patients with GBC or ECC (GBC: 8.2 months; 95% CI, 4.3–11.7; ECC: 16.8 months; 95% CI, 12.7–20.5), and 5.2 months (95% CI, 0.6–9.8) for ICC patients. In both cohorts, therapy was well tolerated. The most common grade 3–4 toxicity was peripheral sensory neuropathy (11 patients). Our data suggest that the CAPOX regimen is a well-tolerated and active treatment option for advanced ECC and GBC but might produce poorer results for ICC.

A randomized second line trial in patients with gemcitabine refractory advanced pancreatic cancer - CONKO 003

4517

Objective: For nearly ten years gemcitabine (G) was standard first line therapy for patients (pts) with advanced pancreatic cancer (APC). There is no consensus about second line therapy after disease progression while receiving G, but 5-FU-based regimens are considered. Results about randomized second line studies in APC are very rare. Our phase II study (ASCO 2002) showed activity of the OFF (oxaliplatin/folinic Acid (FA)/5-fluorouracil (FU) [24h] ) regimen in 23 pts. To examine the impact and the side effects of oxaliplatin we initiated a multicenter phase III study to compare OFF and FF in pts with G refractory APC. Methods: Pts with CT/ MRT confirmed failure with G in first line therapy, Karnofsky Performance Status (KPS) >60%, controlled pain, adequate hematological, renal and liver functions were eligible. Pts were stratified according to duration of first line therapy, KPS and tumor stage. We randomized pts to outpatient treatment with FF (FU 2g/m2 (24h)/ FA 200 mg/m2 (30min) on d1, d8, d15 and d22) or OFF (FF+Oxaliplatin 85mg/m2, d8, d22). In both arms the next cycle started on day 43. Pts were followed with regular staging every 3 months or at any signs of disease progression. Results: Until now we randomized 161 of 165 (planned) pts between 02/2004 and 01/2007. So we expect to present first results (side effects, progression free survival, overall survival) at the meeting.

No significant financial relationships to disclose.

A prospective multicenter phase II trial of capecitabine plus oxaliplatin (CapOx) in advanced biliary system adenocarcinomas: The final results

4136

Background: To investigate the safety and efficacy of capecitabine and oxaliplatin combination therapy (CapOx) in unresectable or metastatic adenocarcinomas of the biliary system. Methods: 65 patients (pts) (27 male, and 38 female) were enrolled (median age, 61 yrs). Major eligibility criteria: histologically proven, measurable disease, age ≤ 75 yrs, ECOG PS 0–2. A total number of 364 cycles (median, 5; range, 1–16) of oxaliplatin (130 mg/m2, d1) plus capecitabine (2 g/m2, d 1–14) were administered 3 weekly for gallbladder carcinoma (GBC) (27 pts), extrahepatic (20 pts), and intrahepatic (18 pts) cholangiocarcinoma (CCC). Response rates were assessed according to WHO criteria. Clinical outcome was determined separately for pts with either GBC/extrahepatic CCC or intrahepatic CCC (mass-forming type). Results: Grade 4 toxicities (WHO): diarrhea in 1 pt (1% of cycles), thrombocytopenia in 1 pt (1%), leukocytopenia in 1 pt (1%), and fever in 2 pts (1%); grade 3 toxicities: nausea/vomiting in 1 pt (1%), diarrhea in 2 pts (1%), thrombocytopenia in 3 pts (2%), and fever in 1 pt (1%). Grade 3/4 peripheral sensory neuropathy (Lévis scale) was found in 13 pts (14% of cycles). Two pts were excluded from study because of oxaliplatin-related allergic reactions. One patient died due to sepsis and another due to cerebral insult during the first treatment cycle. The overall disease control rate in 47 pts with GBC or extrahepatic CCC was 72% (complete response (CR), n = 2 (4%); partial response (PR), n = 11 (23%); stable disease (NC), n = 21 (45%)), whereas progressive disease (PD) was found in 13 pts (28%). In 18 pts with intrahepatic mass-forming CCC, no CR or PR was observed, 5 pts (28%) had SD, and 13 pts (72%) experienced PD. Conclusions: The CapOx protocol is well tolerated and remarkably active for advanced GBC as well as extrahepatic CCC with a disease-control rate of 72%. However, activity appears to be limited in the subset of pts with intrahepatic mass-forming type tumors. Survival data will be presented at the meeting.

No significant financial relationships to disclose.

A prospective, randomized trial of simultaneous pancreatic cancer treatment with enoxaparin and chemotherapy (PROSPECT - CONKO 004)

4110

Background: Approximately 20% of patients (pts) diagnosed with pancreatic adenocarcinoma (PA) develop venous thromboembolism, which may contribute to the dismal prognosis of PA. A small phase II trial suggested an improved survival by the addition of low molecular weight heparin (LMWH) to chemotherapy (Icli et al., ASCO 2003). We conducted a small pilot study which indicated that the addition of enoxaparin to chemotherapy GFFC chemotherapy (see below) is safe and feasible in pts with advanced PA. Furthermore, results of several phase III studies suggest that pts in good performance status may benefit from more intensive chemotherapy regimen (Riess et al; Heinemann et al; ASCO 2005). Based on these considerations we started the multicenter phase III study CONKO 004. Methods: 540 patients are to be recruited into this study. Primary stratification takes place according to Karnowsky performance status and kidney function. Patients with KPS > 80% and normal kidney function receive GFFC ± LMWH (gemcitabine 1 g/m2 (30 min), cisplatin 30 mg/m2 (90 min), 5-fluorouracil 750 mg/m2 (24 h), folinic acid 200 mg/m2 (30 min), d1, 8; q3w ± Enoxaparin 1mg/kg daily s.c.). Pts with KPS < 80 % and increased creatinin plasma levels (>1.3 mg/dl) receive the current standard therapy (gemcitabine 1 g/m2 (30 min), d1, 8, 15; q4w) ± LMWM ± Enoxaparin 1mg/kg daily s.c. After 12 weeks of initial chemotherapy all patients who have not progressed received the standard therapy (gemcitabine 1 g/m2 (30 min), d1, 8, 15; q4w) ± Enoxaparin 40mg daily s.c. Results: From April 2004 to Dezember 2005 140 pts have been recruited in this study. Until now no unexpected serious adverse events concerning severe bleedings were observed in the enoxaparin treatment group. No heparin induced thrombocytopenia (HIT II) was documented. The first interim analysis per protocol is planned after 12 pts. with deep vein thrombosis or thromboembolic events. This interim analysis is expected to be completed in May 2006. Conclusions: Our observations indicate that the addition of enoxaparin—given the dosage mentioned above—to GEM/GFFC is safe, does not change toxicity and maintains activity of chemotherapy in pts with advanced PA. This study is open to recruitment.

No significant financial relationships to disclose.

Phosphorylation of the tau protein sequence 199–205 in the hippocampal CA3 region of Syrian hamsters in adulthood and during aging

Paired helical filaments formed by the abnormally phosphorylated microtubule-associated tau are a main sign of Alzheimer's disease and other neurodegenerative disorders. The hippocampal CA3 region, a brain region with a high degree of synaptic plasticity, is known to be strongly involved in tau hyperphosphorylation in several neurodegenerative diseases. In addition, reversible tau phosphorylation was observed during hibernation in European ground squirrels. The present study provides data on the tau phosphorylation status in the hippocampus of euthermic Syrian hamsters (Mesocricetus auratus), laboratory animals potentially prone to hibernation. Mossy fibers in the CA3 region of all investigated hamsters were immunostained using an antiserum detecting phospho-serine 199 of tau. A similar staining pattern was obtained with CP-13 detecting phospho-serine 202. In contrast, the monoclonal antibody AT8, recognizing both phosphorylated serine 202 and threonine 205, stained the CA3 region only in old hamsters. These findings implicate an additional link between aging, tau phosphorylation and synaptic plasticity. Furthermore, the presented data allow analyses whether tau phosphorylation is reversible in these facultative hibernators and versatile laboratory animal as it was recently shown for the hibernation cycle of European ground squirrels.

Detection of Ki-ras mutations in tissue and plasma samples of patients with pancreatic cancer using PNA-mediated PCR clamping and hybridisation probes

In the present study, we combined the PCR-clamping approach with melting curve analysis using mutant specific hybridisation probes and wild-type specific peptide nucleic acids (PNAs) to determine the genotypes of the most frequent point mutation in codon 12 of the proto-oncogene Ki-ras in tissue and plasma samples of patients with pancreatic cancer. The sensitivity of our assay was 1–5 × 10⁻⁵. The melting curve analysis of tissue samples of four patients revealed two valine mutations, one none-valine mutation and one wild-type sequence. Ki-ras alterations were found in 28% of DNAs (18 out of 64) of nonrelated plasma samples of 10 patients with ductal adenocarcinoma of the pancreas. The valine mutation was the predominantly detected gene alteration (83%). Out of ten patients investigated, four patients (40%) became positive during clinical observation with respect to Ki-ras mutation. All four patients exhibited progressive disease and high levels of tumour marker CA 19-9. In conclusion, the one-step procedure discribed may be a useful clinical tool for analysing Ki-ras point mutations in tissue and plasmas samples. In addition, this method can be adapted for simultanous detection of multiple mutations and quantitation.