Meta-analyses of chemotherapy for locally advanced and metastatic pancreatic cancer: results of secondary end points analyses

In advanced pancreatic cancer, level one evidence has established a significant survival advantage with chemotherapy, compared to best supportive care. The treatment-associated toxicity needs to be evaluated. This study examines the secondary outcome measures for chemotherapy in advanced pancreatic cancer using meta-analyses. A systematic review was undertaken employing Cochrane methodology, with search of databases, conference proceedings and trial registers. The secondary end points were progression-free survival (PFS)/time to progression (TTP) (summarised using the hazard ratio (HR)), response rate and toxicity (summarised using relative risk). There was no significant advantage of 5FU combinations vs 5FU alone for TTP (HR=1.02; 95% CI=0.85-1.23) and toxicity. Progression-free survival (HR 0.78; CI 0.70-0.88), TTP (HR=0.85; 95% CI=0.72-0.99) and overall response rate (RR=0.56; 95% CI=0.46-0.68) were significantly better for gemcitabine combination chemotherapy, but offset by the greater grade 3/4 toxicity thrombocytopenia (RR=1.94; 95% CI=1.32-2.84), leucopenia (RR=1.46; 95% CI=1.15-1.86), neutropenia (RR=1.48; 95% CI=1.07-2.05), nausea (RR=1.77; 95% CI=1.37-2.29), vomiting (RR=1.64; 95% CI=1.24-2.16) and diarrhoea (RR=2.73; 95% CI=1.87-3.98). There is no significant advantage on secondary end point analyses for administering 5FU in combination over 5FU alone. There is improved PFS/TTP and response rate, with gemcitabine-based combinations, although this comes with greater toxicity.

Meta-analyses of chemotherapy for locally advanced and metastatic pancreatic cancer

PURPOSE

There are a large number of randomized controlled trials involving chemotherapy in the management of advanced pancreatic cancer. Several chemotherapeutic agents, either alone or in combination with other chemotherapy or novel agents, have been used. The aim of these meta-analyses was to examine the different therapeutic approaches, and the comparisons examined were as follows: chemotherapy versus best supportive care; fluorouracil (FU) versus FU combination chemotherapy; gemcitabine versus FU; and gemcitabine versus gemcitabine combination chemotherapy.

METHODS

Relevant trials were identified by searching databases, trial registers, and conference proceedings. The primary end point was overall survival.

RESULTS

One hundred thirteen randomized controlled trials were identified, of which 51 trials involving 9,970 patients met the inclusion criteria. Chemotherapy improved survival compared with best supportive care (hazard ratio [HR] = 0.64; 95% CI, 0.42 to 0.98). FU-based combination chemotherapy did not result in better overall survival compared with FU alone (HR = 0.94; 95% CI, 0.82 to 1.08). There was insufficient evidence of a survival difference between gemcitabine and FU, but the wide CI includes clinically important differences in both directions, making a clear conclusion difficult (HR = 0.75; 95% CI, 0.42 to 1.31). Survival was improved after gemcitabine combination chemotherapy compared with gemcitabine alone (HR = 0.91; 95% CI, 0.85 to 0.97).

CONCLUSION

There was a significant survival benefit for chemotherapy over best supportive care and gemcitabine combinations over gemcitabine alone. This supports the use of gemcitabine-based combination chemotherapy in the treatment of advanced pancreatic cancer.

FOLFOX-6 combination as the first-line treatment of locally advanced and/or metastatic pancreatic cancer

OBJECTIVE

Advanced pancreatic carcinoma (APC) has a poor prognosis and chemotherapy remains the most common approach. Gemcitabine was the only drug recently approved for use as single agent therapy in APC. However, the combination of oxaliplatin and 5-fluorouracil (5-FU) has shown some promising results. This phase II trial was conducted to investigate the efficacy of oxaliplatin, 5-FU, and folinic acid (FOLFOX-6) in previously untreated APC patients.

METHODS

We studied response rate, time to progression, and toxicity profile. Treatment included oxaliplatin 100 mg/m2 and folinic acid 400 mg/m2 on day 1 followed by a 5-FU bolus 400 mg/m2 and a 46-hour infusion of 3000 mg/m2 every 2 weeks.

RESULTS

From January 2003 through December 2004, 30 eligible patients were included. Median age was 65 (range, 38-75). There were 22 patients who had metastatic disease and 29 had an adenocarcinoma. A total of 181 cycles were delivered with a mean of 6 cycles per patient. There were 23 patients evaluable for response. There were 8 patients with partial response (27.6% response rate) and 10 with stable disease status (34.5%), while tumor growth control was found in 62% of the patients. Recorded toxicities of grade 3/4 were: neutropenia (26.67%), thrombocytopenia and anemia (10% each), diarrhea (6.67%), and mucositis (3.33%). Neurosensory toxicity was mild. The median time to progression and the median survival were 4 and 7.5 months, respectively.

CONCLUSION

In patients with APC, FOLFOX-6 regimen achieved an interesting response rate within a tolerable level of toxicity. This regimen seems to warrant further controlled investigation to confirm its efficacy.

Locally advanced pancreatic cancer: current therapeutic approach

Even though pancreatic cancer accounts for only 2% of all cancer diagnoses in the U.S., it is the fourth-leading cause of cancer death and one of the most difficult malignancies to manage. Because of the usually late onset of symptoms, only 10%-15% of patients present with resectable disease, whereas the remaining 85%-90% present with locally advanced unresectable or metastatic disease. Despite a lack of consistent evidence from previous clinical trials, chemotherapy in addition to radiation therapy is the most commonly used approach in treating locally advanced pancreatic cancer. The most appropriate chemotherapy in combination with radiation is still debatable between 5-fluorouracil and gemcitabine, and novel trends to prevent resistance and enhance efficacy incorporate biologically targeted agents. This paper reviews the current management options, controversies, and ongoing and future directions for the treatment of locally advanced adenocarcinoma of the pancreas.

Meta-analysis on inoperable pancreatic cancer: a comparison between gemcitabine-based combination therapy and gemcitabine alone

AIM

To compare gemcitabine-based combination therapy and gemcitabine (GEM) alone in patients with advanced pancreatic cancer (APCa) through meta-analysis.

METHODS

MEDLINE and EMBASE searches were supplemented by information from trial registers of randomized controlled trials (RCTs) for GEM-based combination therapy and GEM alone for APCa. A quantitative meta-analysis was carried out by two reviewers based on the inclusion criteria from all available RCTs. The meta-analysis involved overall survival (OS), objective remission rate (ORR), clinical benefit rate (CBR), time to progress/progress free survival (TTP/PFS) and toxicity.

RESULTS

The meta-analysis included 22 RCTs. There was significant improvement in the GEM combination group with regard to the 6-mo survival rate (RD = 0.04, 95% CI 0.01-0.06, P = 0.008), 1-year survival rate (RD = 0.03, 95% CI 0.01-0.05, P = 0.01), ORR (RD = 0.04, 95% CI 0.01-0.07, P = 0.02), CBR (RD = 0.10, 95% CI 0.02-0.17, P = 0.01) and 6-mo TTP/PFS (RD = 0.07, 95% CI 0.04-0.10, P < 0.00001). However, the Grade 3-4 toxicity set by WHO was higher for the GEM combination group for neutropenia (RD = 0.05, 95% CI 0.01-0.10, P = 0.02), thrombocytopenia (RD = 0.05, 95% CI 0.02-0.08, P = 0.002) and vomiting/nausea (RD = 0.03, 95% CI 0.00-0.05, P = 0.02).

CONCLUSION

GEM-based combination therapy may improve the overall survival and palliation in optimal patients with APCa as compared with GEM alone.

Current therapies and advances in the treatment of pancreatic cancer

Pancreatic cancer is a common, highly lethal disease with a rising incidence. In the last years continued efforts in pancreatic cancer research have led to a change in the classic approaches and to the development of new biological agents that appear to show promise. Adjuvant chemotherapy with gemcitabine has recently demonstrated better survival outcomes following surgical resection compared to no treatment, especially in patients with positive margins or lymph nodes. The addition of anti-VEGF agents to adjuvant regimens could improve long-term outcomes. In locally advanced disease, neoadjuvant regimens have not produced complete remissions, but partial responses have been reported ranging between 10 and 20%, with conflicting survival results. Combination trials with radiochemotherapy and new drugs appear well tolerated with encouraging preliminary results. In the metastatic setting, novel chemotherapeutic combinations and molecular targeted agents have shown promise in improving outcomes. To date, second line therapy is increasingly proposed and may even provide survival benefits in the future. This article summarizes the current standards of therapy for patients with resectable, advanced and metastatic pancreatic cancer.