A multicenter phase II study of gemcitabine and S-1 combination chemotherapy in patients with unresectable pancreatic cancer. Cancer Chemother Pharmacol. 2010;65:527-536. [PMID: 19578850 DOI: 10.1007/s00280-009-1059-9]

A phase II study of gemcitabine, erlotinib and S-1 in patients with advanced pancreatic cancer

Background: We evaluated the efficacy and safety of gemcitabine in combination with erlotinib and S-1 for the treatment of advanced pancreatic cancer.

Methods: Chemotherapy-naïve patients with pathologically-proven locally advanced, recurrent, or metastatic pancreatic adenocarcinoma were assessed for eligibility. Gemcitabine was administered at 1,000 mg/m² intravenously on days 1 and 8, erlotinib was administered at 100 mg/day on days 1-21, and S-1 was administered at 60 mg/m² on days 1-14 every 21 days and continued to a maximum of 8 cycles of treatment. Dose escalation of S-1 to 80 mg/m² was permitted from the second cycle for pre-defined tolerable patients.

Results: Thirty-seven patients (median age 61.5 years) were enrolled. A total of 140 cycles of chemotherapy were administered (median of 3.8; range 1-8 cycles). Toxicities were evaluated in 36 patients, and the responses were evaluated in 32 patients. Major grade 3/4 toxicities included neutropenia (25%), febrile neutropenia (2.8%), fatigue (22.2%), infection (8.3%), vomiting (5.6%), and mucositis (5.6%). The confirmed overall response rate was 12.5% [95% confidence interval (CI), 5.1-28.9%] and the disease control rate was 71.9% (95% CI, 56.8-86.3%). The median progression-free survival and overall survival were 3.7 months (95% CI, 2.8-4.6 months) and 6.7 months (95% CI, 3.4-9.9 months), respectively.

Conclusion: The combination of gemcitabine, erlotinib, and S-1 provided an acceptable toxicity profile and modest clinical benefits in patients with advanced pancreatic cancer.

Evaluation of Phase II Trial Design in Advanced Pancreatic Cancer

OBJECTIVES

We evaluated how well phase II trials in locally advanced and metastatic pancreatic cancer (LAMPC) meet current recommendations for trial design.

METHODS

We conducted a systematic review of phase II first-line treatment trial for LAMPC. We assessed baseline characteristics, type of comparison, and primary end point to examine adherence to the National Cancer Institute recommendations for trial design.

RESULTS

We identified 148 studies (180 treatment arms, 7505 participants). Forty-seven (32%) studies adhered to none of the 5 evaluated National Cancer Institute recommendations, 62 (42%) followed 1, 31 (21%) followed 2, and 8 (5%) followed 3 recommendations. Studies varied with respect to the proportion of patients with good performance status (range, 0%-80%) and locally advanced disease (range, 14%-100%). Eighty-two (55%) studies concluded that investigational agents should progress to phase III testing; of these, 24 (16%) had documented phase III trials. Three (8%) phase III trials demonstrated clinically meaningful improvements for investigational agents. One of 38 phase II trials that investigated biological investigational agents was enriched for a biomarker.

CONCLUSIONS

Phase II trials do not conform well to current recommendations for trial design in LAMPC.

Effect of S-1 on survival outcomes in 838 patients with advanced pancreatic cancer: A 7-year multicenter observational cohort study in Taiwan

Objective

Studies have rarely explored the efficacy of S‐1 in treating advanced pancreatic cancer outside Japan. This study compared the survival outcomes of patients with advanced pancreatic cancer treated with S‐1 with the survival outcomes of those without S‐1 treatment before and after S‐1 reimbursement was introduced in Taiwan in June of 2014.

Method

We retrospectively analyzed 838 patients with locally advanced or metastatic pancreatic cancer who underwent palliative chemotherapy from 2010 to 2016 at 4 institutes in Taiwan. For survival analysis, patients were categorized into two groups according to whether they received S‐1 treatment as palliative chemotherapy after diagnosis: (a) S‐1‐treated (n = 335) and (b) non‐S‐1‐treated (n = 503) groups.

Results

The median overall survival was longer in the S‐1‐treated group than in the non‐S‐1‐treated group (10.7 vs 6.0 mo, P < 0.001). Subgroup survival analyses showed that the S‐1‐treated group had more favorable outcomes than the non‐S‐1‐treated group in terms of stage III (19.6 vs 10.1 mo, P < 0.001) and stage IV (8.5 vs 5.3 mo, P < 0.001) disease. The disease control rates were 43.6% and 32.8% (P < 0.001) in patients treated with and without S‐1 in the first‐line setting, respectively. In multivariate analysis, exposure to S‐1 treatment was an independent prognosticator for survival.

Conclusion

Our results support the clinical use of S‐1 as the treatment of choice for patients with locally advanced or metastatic pancreatic cancer, particularly in resource‐limited situations.

The incidence and survival of pancreatic cancer by histology, including rare subtypes: a nation-wide cancer registry-based study from Taiwan

Studies have indicated a significant rise in the incidence of pancreatic adenocarcinoma. However, the epidemiology of other rare histologic subtypes of pancreatic cancer is not well understood. This study analyzed the incidence and survival of pancreatic cancer in Taiwan by histologic subtype, sex, age group, and year of diagnosis. The incidence trends of pancreatic cancer in Taiwan from 2002 to 2013 were calculated using data from the Taiwan Cancer Registry. The survival of pancreatic cancer patients was assessed using the life-table method and Cox proportional hazards analysis. The incidence of pancreatic cancer increased from 4.62 per 100,000 in 2002 to 6.04 per 100,000 in 2013 in Taiwan. The most common histologic subtype of pancreatic cancer was adenocarcinoma followed by carcinoma and neuroendocrine tumors (NETs). Adenocarcinoma and NETs showed a rapid increase in incidence, while the incidences of other subtypes did not change significantly. Patients with adenocarcinoma showed a poor survival with a 5-year survival of 5.2%. Patients with endocrinomas, NETs, and lymphoma displayed a better survival than those with adenocarcinoma, with a 5-year survival ranging from 41.8% to 59.1%. The survival of adenocarcinoma, lymphoma, and NETs improved after the introduction of novel therapies. Understanding the risk factors and identifying the biomarkers for the early diagnosis of pancreatic cancer are important to prevent the development and improve the survival of pancreatic cancer.

Toxicity of chemotherapy regimens in advanced and metastatic pancreatic cancer therapy: A network meta-analysis

This network meta-analysis is adopted in order to compare the toxicity of different chemotherapy regimens in the treatment of advanced/metastatic pancreatic cancer (PC). Randomized controlled trials (RCTs) about different chemotherapy regimens for advanced/metastatic PC were included in this network meta-analysis using Cochrane Library and PubMed electronic databases. The network meta-analysis was performed to combine direct and indirect evidence in order to calculate the odd ratios (OR) and draw a surface under the cumulative ranking (SUCRA) curve. A total of 19 RCTs were enrolled in this network meta-analysis including 12 chemotherapy regimens (Gemcitabine, Gemcitabine + S-1 [tegafur], Gemcitabine + nab-paclitaxel, Gemcitabine + Capecitabine, Gemcitabine + Cisplatin, FOLFIRINOX [oxaliplatin + irinotecan + fluorouracil + leucovorin], Gemcitabine + oxaliplatin, Gemcitabine + irinotecan, Gemcitabine + Exatecan, Gemcitabine + pemetrexed, Gemcitabine + 5-FU, S-1). The incidence of anemia of Gemcitabine + Capecitabine regimen was higher compared with Gemcitabine regimen, Gemcitabine + pemetrexed regimen exhibited the highest incidence rates of anemia and neutropenia; while Gemcitabine + S-1, Gemcitabine + Cisplatin and FOLFIRINOX regimens exhibited the highest incidence rates of neutropenia. However, S-1 regimen exhibited lower incidence rates of leukopenia and thrombocytopenia. Moreover, the incidence rates of nausea/vomiting and rash of Gemcitabine + S-1 regimen were higher compared with Gemcitabine regimen, while Gemcitabine + Cisplatin regimen had the highest incidence rate of nausea/vomiting. This study demonstrated that the hematologic toxicity of S-1 regimen was the lowest, while Gemcitabine regimen exhibited the lowest incidence rate of non-hematologic toxicity, providing guidance for the treatment of advanced/metastatic PC.

Combined gemcitabine and S-1 chemotherapy for treating unresectable hilar cholangiocarcinoma: a randomized open-label clinical trial

Although the combination of cisplatin and gemcitabine (GEM) is considered the standard first-line chemotherapy against unresectable hilar cholangiocarcinoma (HC), its efficacy is discouraging. The present randomized open-label clinical trial aimed to evaluate the efficacy and safety of the GEM plus S-1 (GEM-S-1) combination against unresectable HC. Twenty-five patients per group were randomly assigned to receive GEM, S-1 or GEM-S-1. Neutropenia (56%) and leukopenia (40%) were the most common chemotherapy-related toxicities in the GEM-S-1 group. Median overall survival (OS) in the GEM-S-1, GEM and S-1 groups was 11, 10 and 6 months, respectively. GEM plus S-1 significantly improved OS compared to S-1 monotherapy (OR=0.68; 95%CI, 0.50–0.90; P=0.008). Median progression-free survival (PFS) times in the GEM-S-1, GEM and S-1 groups were 4.90, 3.70 and 1.60 months, respectively. GEM plus S-1 significantly improved PFS compared to S-1 monotherapy (OR=0.50; 95%CI, 0.27–0.91; P=0.024). Response rates were 36%, 24% and 8% in the GEM-S-1, GEM and S-1 groups, respectively. A statistically significant difference was found in response rates between the gemcitabine-S-1 and S-1 groups (36% vs 8%, P=0.017). Patients with CA19-9<466 U/ml were more responsive to chemotherapeutic agents than those with CA19-9≥571 U/ml (88.9% vs 0%, P<0.001). We conclude that the combination of GEM plus S-1 provides a better OS, PFS and response rate than S-1 monotherapy, but it did not significantly differ from GEM monotherapy. (ChiCTR-TRC-14004733).

Phase I study assessing the feasibility of the triple combination chemotherapy of SOXIRI (S-1/oxaliplatin/irinotecan) in patients with unresectable pancreatic ductal adenocarcinoma

BACKGROUND

The objective of this study was to determine the recommended dose (RD) of a biweekly S-1, oxaliplatin, and irinotecan (SOXIRI) regimen in patients with unresectable pancreatic ductal adenocarcinoma.

METHODS

This phase I study used a traditional "3+3" dose-escalation design, with four dose levels. A dose-escalation schedule consisted of two doses of S-1 (60 and 80 mg/m(2) twice daily) for 2 weeks in alternate-day administration, three doses of irinotecan (125, 150, and 180 mg/m(2)) on day 1, and a single dose of oxaliplatin (85 mg/m(2)) on day 1 of a 2-week cycle. Dose-limiting toxicities (DLTs) were assessed in the first four cycles to determine the maximum tolerated dose. This clinical study was registered at UMIN000014339.

RESULTS

Fifteen patients received this regimen (median, eight cycles; range 4-12). At dose level 3 (S-1, 80 mg/m(2); irinotecan, 150 mg/m(2)), 2/6 patients experienced DLTs of grade 3 fatigue and grade 4 neutropenia. At dose level 4, all three patients experienced DLTs: grade 3 fatigue (n = 1) and grade 4 neutropenia (n = 2). The RD was 80, 85, and 150 mg/m(2) of S-1, oxaliplatin, and irinotecan, respectively. We found the following: response rate, 47 %; disease control rate, 80%; median progression-free survival, 6.7 months; overall survival, 13.4 months.

CONCLUSIONS

The SOXIRI regimen's RD is 80, 85, and 150 mg/m(2) of S-1, oxaliplatin, and irinotecan, respectively.

Gemcitabine plus S-1: a hopeful frontline treatment for Asian patients with unresectable advanced pancreatic cancer

OBJECTIVE

Gemcitabine-based chemotherapy is widely used for unresectable advanced pancreatic cancer which contains locally advanced and metastatic pancreatic cancer. We performed meta-analysis to examine whether gemcitabine plus S-1 could improve treatment efficacy as first-line chemotherapy for those patients when compared with gemcitabine alone.

METHODS

STATA was used to estimate the summary hazard ratios or odds ratios and their 95% confidence intervals. Heterogeneity among trials was examined by Cochran's χ(2) test. Publication bias was evaluated by Begg's and Egger's tests. Subgroup analysis based on the extent of disease was performed.

RESULTS

Four randomized controlled trials including 878 Asian patients were analyzed. In total meta-analysis, gemcitabine plus S-1 significantly improved overall survival (hazard ratio, 0.82; 95% confidence interval, 0.70-0.96; P = 0.015), progression-free survival (hazard ratio, 0.64; 95% confidence interval, 0.55-0.74; P < 0.001), overall response rate (odds ratio, 3.00; 95% confidence interval, 2.04-4.41; P < 0.001) and disease control rate (odds ratio, 1.78; 95% confidence interval, 1.32 to 2.39; P < 0.001), and was associated with more but manageable hematologic (leukocytopenia, neutropenia, thrombocytopenia) and non-hematologic (diarrhea, stomatitis, nausea, rash) adverse events. In subgroup analysis, gemcitabine plus S-1, comparing with gemcitabine, significantly improved overall survival in locally advanced patients (hazard ratio, 0.69; 95% confidence interval, 0.48 to 0.99; P = 0.022) but not in metastatic patients (hazard ratio, 0.75; 95% confidence interval, 0.46-1.23; P = 0.256).

CONCLUSION

This meta-analysis confirmed the survival benefits of gemcitabine plus S-1 as first-line treatment for unresectable advanced pancreatic cancer at least in Asia, while good Eastern Cooperative Oncology group performance status was warranted. Importantly, we highlighted the significant overall survival benefit of gemcitabine plus S-1 in locally advanced patients but not in metastatic patients.

Gemcitabine Compared With Gemcitabine and S-1 Combination Therapy in Advanced Pancreatic Cancer: A Systematic Review and Meta-Analysis

Several reports suggest that gemcitabine (GEM) plus S-1 combination (GS) is associated to prolong the survival in patients with unresectable pancreatic cancer (PC). We conducted a systemic review and meta-analysis of studies comparing the safety and efficacy of GS versus GEM.Summary data from randomized trials and retrospective studies were searched in PubMed, EMBASE, Web of Science, and the Cochrane Library. Statistical analyses were conducted to calculate the hazard ratios (HRs) and relative risk (RR) with 95% confidence intervals (CIs) using random-effects models. Subgroup analyses based on the chemotherapy cycles were performed to explore the efficacy and toxicity for therapy. Sensitivity analyses were conducted by removing specific studies to assess the effects of study quality.Between January 2004 and August 2012, 4 RCTs and 2 retrospective studies including a total of 1025 cases were identified. The overall survival (OS) (HR: 0.82; 95% CI, 0.70-0.96; P = 0.01) and progression-free survival (PFS) (HR: 0.65; 95% CI, 0.55-0.77; P < 0.001) for the GS arm were significantly longer than the GEM arm. The differences in objective response rate (ORR) (RR: 1.24; 95% CI, 1.17-1.33; P < 0.001) and disease control rate (DCR) were also better in the GS arm (RR: 1.37; 95% CI, 1.19-1.59; P < 0.001). Grades 3 to 4 toxicities in both the groups were similar except neutropenia and diarrhea, which were more frequent in the GS arm (P < 0.001). In the subgroup analysis, the cycle for chemotherapy every 4 weeks has equivalent efficacy and less toxicity than regimens every 3 weeks in the GS arm.The current meta-analysis suggested that GEM significantly prolonged OS and PFS when added to S-1 combination in patients with unresectable PC. GS therapy also offers better ORR and DCR than GEM monotherapy and no unexpected toxicity was evident.

Phase II clinical trials on investigational drugs for the treatment of pancreatic cancers

INTRODUCTION

Despite some recent advances in treatment options, pancreatic cancer remains a devastating disease with poor outcomes. In a trend contrary to most malignancies, both incidence and mortality continue to rise due to pancreatic cancer. The majority of patients present with advanced disease and there are no treatment options for this stage that have demonstrated a median survival > 1 year. As the penultimate step prior to Phase III studies involving hundreds of patients, Phase II clinical trials provide an early opportunity to evaluate the efficacy of new treatments that are desperately needed for this disease.

AREAS COVERED

This review covers the results of published Phase II clinical trials in advanced pancreatic adenocarcinoma published within the past 5 years. The treatment results are framed in the context of the current standards of care and the historic challenge of predicting Phase III success from Phase II trial results.

EXPERT OPINION

Promising therapies remain elusive in pancreatic cancer based on recent Phase II clinical trial results. Optimization and standardization of clinical trial design in the Phase II setting, with consistent incorporation of biomarkers, is needed to more accurately identify promising therapies that warrant Phase III evaluation.

S-1 in the treatment of pancreatic cancer

S-1 is an oral 5-fluorouracil (5-FU) prodrug, which is designed to improve the antitumor activity of 5-FU by inhibiting dihydropyrimidine dehydrogenase, the key enzyme of 5-FU catabolism. Recently, two important studies on the clinical use of S-1 for pancreatic cancer have been reported from Japan. In the first study (GEST study), S-1 demonstrated non-inferiority to gemcitabine (GEM) in overall survival (OS) for metastatic or locally advanced pancreatic cancer, but combination chemotherapy with GEM and S-1 did not show superiority to GEM in OS. In the second study (JASPAC-01 study), S-1 showed superiority to adjuvant chemotherapy with GEM in OS in patients with resected pancreatic cancer. In addition to GEM, S-1 is now regarded as the key drug in the management of pancreatic cancer in Japan. To date, many studies have investigated the effectiveness of S-1 in various settings, such as first-line chemotherapy for metastatic or locally advanced pancreatic cancer, second-line chemotherapy after GEM failure, and chemoradiotherapy for locally advanced disease. In this review, we focus on recent clinical trials of S-1-based chemotherapy for advanced pancreatic cancer.

Neoadjuvant chemotherapy with gemcitabine and S-1 for resectable and borderline pancreatic ductal adenocarcinoma: results from a prospective multi-institutional phase 2 trial

BACKGROUND

Surgical resection is the only curative strategy for pancreatic ductal adenocarcinoma (PDAC), but recurrence rates are high even after purported curative resection. First-line treatment with gemcitabine and S-1 (GS) is associated with promising antitumor activity with a high response rate. The aim of this study was to assess the feasibility and efficacy of GS in the neoadjuvant setting.

METHODS

In a multi-institutional single-arm phase 2 study, neoadjuvant chemotherapy (NAC) with gemcitabine and S-1, repeated every 21 days, was administered for two cycles (NAC-GS) to patients with resectable and borderline PDAC. The primary end point was the 2-year survival rate. Secondary end points were feasibility, resection rate, pathological effect, recurrence-free survival, and tumor marker status.

RESULTS

Of 36 patients enrolled, 35 were eligible for this clinical trial conducted between 2008 and 2010. The most common toxicity was neutropenia in response to 90% of the relative dose intensity. Responses to NAC included radiological tumor shrinkage (69%) and decreases in CA19-9 levels (89%). R0 resection was performed for 87% in resection, and the morbidity rate (40%) was acceptable. The 2-year survival rate of the total cohort was 45.7%. Patients who underwent resection without metastases after NAC-GS (n = 27) had an increased median overall survival (34.7 months) compared with those who did not undergo resection (P = 0.0017).

CONCLUSIONS

NAC-GS was well tolerated and safe when used in a multi-institutional setting. The R0 resection rate and the 2-year survival rate analysis are encouraging for patients with resectable and borderline PDAC.

A multicentre randomised phase II trial of gemcitabine alone vs gemcitabine and S-1 combination therapy in advanced pancreatic cancer: GEMSAP study

Background:

This randomised phase II trial compared gemcitabine alone vs gemcitabine and S-1 combination therapy in advanced pancreatic cancer.

Methods:

Patients were randomly assigned to 4-week treatment with gemcitabine alone (1000, mg m⁻² gemcitabine by 30-min infusion on days 1, 8, and 15) or gemcitabine and S-1 combination therapy (1000, mg m⁻² gemcitabine by 30-min infusion on days 1 and 15 and 40 mg m⁻² S-1 orally twice daily on days 1–15). The primary end point was progression-free survival (PFS).

Results:

Between July 2006 and February 2009, 106 patients were enrolled. The PFS in gemcitabine and S-1 combination arm was significantly longer than in gemcitabine arm (5.4 vs 3.6 months), with a hazard ratio of 0.64 (P=0.036). Overall survival (OS) for gemcitabine and S-1 combination was longer than that for gemcitabine monotherapy (13.5 vs 8.8 months), with a hazard ratio of 0.72 (P=0.104). Overall, grade 3 or 4 adverse events were similar in both arms.

Conclusion:

Gemcitabine and S-1 combination therapy demonstrated longer PFS in advanced pancreatic cancer. Improved OS duration of 4.7 months was found for gemcitabine and S-1 combination therapy, though this was not statistically significant.

Optimal combination of radiofrequency ablation with chemoradiotherapy for locally advanced pancreatic cancer

Problems have been reported in the treatment of pancreatic cancer with radiofrequency ablation (RFA), such as the friability of the organ itself. This report presents possible solutions to such problems. Although our patient suffered from locally advanced unresectable pancreatic cancer, she remained well at 18 mo after RFA with no evidence of recurrence. To ameliorate the side effects of RFA, after a palliative bypass procedure, the subject was treated with combined radiotherapy and chemotherapy. After this regimen had been administered, a contrast-enhanced computed tomography scan confirmed that RFA is a viable approach to the treatment of pancreatic cancer as the chemoradiotherapy had resulted in marked tumor shrinkage and pancreatic fibrosis; i.e., sufficient tumor ablation was achieved without serious RFA-related complications, such as pancreatitis or pancreatic fistulae. The present case suggests that RFA combined with preceding chemoradiotherapy is safe and effective for the palliative treatment of locally advanced pancreatic cancer.

Combinational therapy: new hope for pancreatic cancer?

Pancreatic cancer is a devastating disease with a low overall survival rate. Chemotherapy is the most common treatment for patients presenting with advanced pancreatic cancer. Gemcitabine achieves a modest improvement in overall survival and is the gold standard for advanced pancreatic cancer treatment. Capecitabine and S-1, derivatives of 5-fluorouracil (5-FU), offers minimal clinical benefits. Folfirinox represents a new and aggressive regimen that might benefit patients of metastatic pancreatic cancer with good performance status. Other chemotherapy drugs such as platinums and irinotecan do not provide significant improvement in overall survival, but have been used as part of combinational therapies. Comparing to systemically delivered chemotherapy, regional intra-arterial chemotherapy achieves higher local drug concentration in tumors with lower systemic drug toxicity, and may serve as a better treatment regimen. Although there have been progress made in chemotherapeutic strategies against pancreatic cancer, the overall survival is not significantly improved in the last decade. Recently, development of chemotherapy in combination with molecular targeted therapies holds great promise in pancreatic cancer treatment, especially in patients with metastatic disease. Growing bodies of preclinical and clinical evidences indicate that the combination of conventional modalities with specific molecular targeted therapy increase the efficacy of the monotherapy without an increase in toxicity. In this review, we summarized the current regimens of chemotherapy and molecular targeted therapy for advanced pancreatic cancer and highlighted the novel combinational treatments tested in recent clinical trials.

Phase I/II study of gemcitabine as a fixed dose rate infusion and S-1 combination therapy (FGS) in gemcitabine-refractory pancreatic cancer patients

PURPOSE

There is no standard regimen for gemcitabine (Gem)-refractory pancreatic cancer (PC) patients. In a previous phase II trial, S-1 was found to exhibit marginal efficacy. Gem administration by fixed dose rate infusion of 10 mg/m(2)/min (FDR-Gem) should maximize the rate of intracellular accumulation of gemcitabine triphosphate and might improve clinical efficacy. We conducted the phase I/II of FDR-Gem and S-1 (FGS) in patients with Gem-refractory PC.

METHODS

The patients received FDR-Gem on day 1 and S-1 orally twice daily on days 1-7. Cycles were repeated every 14 days. Patients were scheduled to receive Gem (mg/m(2)/week) and S-1 (mg/m(2)/day) at four dose levels in the phase I: 800/80 (level 1), 1,000/80 (level 2), 1,200/80 (level 3) and 1,200/100 (level 4). Forty patients were enrolled in the phase II study at recommended dose.

RESULTS

The recommended dose was the level 3. In the phase II, a partial response has been confirmed in seven patients (18%). The median overall survival time and median progression-free survival time are 7.0 and 2.8 months, respectively. The common adverse reactions were anorexia, leukocytopenia and neutropenia.

CONCLUSION

This combination regimen of FGS is active and well tolerated in patients with Gem-refractory PC.

Multicenter phase II study of gemcitabine and S-1 combination therapy (GS Therapy) in patients with metastatic pancreatic cancer

OBJECTIVE

The aim of this multicenter Phase II study was to assess the efficacy and toxicity of gemcitabine and S-1 combination therapy for metastatic pancreatic cancer.

METHODS

Chemotherapy-naïve patients with histologically or cytologically proven metastatic pancreatic adenocarcinoma were eligible for this study. Gemcitabine was administered at a dose of 1000 mg/m(2) over 30 min on days 1 and 8, and oral S-1 at a dose of 40 mg/m(2) twice daily from days 1 to 14, repeated every 3 weeks.

RESULTS

A total of 55 patients were included and the efficacy and toxicity were analyzed in 54 patients who received at least one dose of gemcitabine and S-1 combination therapy. Although no complete response was seen, a partial response was achieved in 24 patients, resulting in an overall response rate of 44.4% (95% confidence interval: 30.9-58.6%). The median progression-free survival was 5.9 months (95% confidence interval: 4.1-6.9 months) and the median overall survival was 10.1 months (95% confidence interval: 8.5-10.8 months) with a 1-year survival rate of 33.0%. The major Grade 3-4 toxicities were neutropenia (80%), leucopenia (59%), thrombocytopenia (22%), anorexia (17%) and rash (7%). Hematological toxicity was mostly transient and there was only one episode of febrile neutropenia ≥Grade 3.

CONCLUSIONS

Gemcitabine and S-1 combination therapy produced a high response rate with good survival in patients with metastatic pancreatic cancer. A randomized Phase III study to confirm the efficacy of gemcitabine and S-1 combination therapy is ongoing.

Prognostic implications of intraoperative radiotherapy for unresectable pancreatic cancer

BACKGROUND/AIMS

To assess the prognostic effect of intraoperative radiotherapy (IORT) in unresectable pancreatic cancer.

METHODS

We reviewed 198 patients with unresectable pancreatic cancer, which was found during experimental laparotomy. Liver metastasis was observed in 70 patients, peritoneal metastasis in 44, liver and peritoneal metastasis in 23 and locally advanced tumor in 61. Treatment consisted of IORT with or without postoperative chemotherapy. Overall survival (OS) and prognostic factors were evaluated for each pattern of disease spread.

RESULTS

IORT was performed in 120 patients, and chemotherapy was administered in 80. Sixty patients did not receive either treatment. OS in the untreated group was significantly inferior to that for IORT alone and IORT plus gemcitabine (GEM)-based chemotherapy. IORT and GEM-based chemotherapy were identified as independent prognostic factors [hazard ratio (HR) = 0.51, p < 0.001; HR = 0.43, p < 0.001]. IORT was an independent prognostic determinant for patients with peritoneal metastasis (HR = 0.24, p = 0.011) but not for those with liver metastasis (HR = 0.78, p = 0.381).

CONCLUSION

IORT followed by GEM-based chemotherapy is the recommended treatment strategy in unresectable pancreatic cancer. and IAP.

Results of a phase II trial of S-1 as first-line treatment of metastatic pancreatic cancer (CESAR-study group)

PURPOSE

S-1, an oral fluoropyrimidine derivative, has previously demonstrated anticancer efficacy in pancreatic cancer (PC), predominantly in Asian populations. This study evaluated the antitumor effect and safety of S-1 in Caucasian patients with metastatic PC.

METHODS

Chemotherapy-naïve patients received S-1 orally at 30 mg/m(2) twice daily (BID) for 2 weeks, repeated every 3 weeks. Primary endpoint was ORR. Secondary endpoints included PFS, OS and safety assessment. The trial had a Simon's two-stage design with 22 patients evaluable for efficacy in stage 1 and an additional 18 patients in stage 2, if ≥3/22 patients had a confirmed response at the first stage.

RESULTS

Three out of 27 patients showed PR, however, detection of asymptomatic brain metastases in one of them prevented this study from proceeding to stage 2. The median PFS and OS for all patients was 3.5 and 9.1 months, respectively. The median duration of disease control for patients with SD or PR (n = 17) was 4.3 months. S-1 was well tolerated; fatigue was the most frequent grade 3/4 adverse event.

CONCLUSIONS

Efficacy data of PFS and OS are at least comparable to gemcitabine, the current standard of care. S-1 is active in Caucasian patients with metastatic PC.

Contribution of thymidylate synthase to gemcitabine therapy for advanced pancreatic cancer

OBJECTIVES

Thymidylate synthase (TS) inhibitors activate human equilibrative nucleoside transporter 1. We evaluated the contribution of TS expression to determine a treatment method providing an effect from gemcitabine (GEM).

METHODS

The expression of 5-fluorouracil (5-FU) and GEM metabolic factors (5-FU: TS, dihydropyrimidine dehydrogenase, orotate phosphoribosyltransferase; GEM: human equilibrative nucleoside transporter 1, deoxycytidine kinase, cytidine deaminase, 5'-nucleotidase) were studied in 7 pancreatic cancer cell lines by Western blotting, and drug resistance was evaluated by 3-[4,5-dimethylthiazol]-2,5-dephenyl tetrazolium bromide assay. The expression of 5-FU factors was observed immunohistochemically in resected pancreatic cancer specimens.

RESULTS

Gemcitabine concentrations that inhibited colony formation by 50% correlated with TS protein expression (P = 0.0169). With a 5-FU non-growth-inhibiting dose, GEM concentrations that inhibited colony formation by 50% were significantly reduced by one fourth to one tenth. Knockout of TS expression by small interfering RNA decreased resistance to GEM in the cell lines (P = 0.0019). Immunohistochemically, TS expression related to disease-free survival time of patients treated with GEM (P = 0.0224). A high expression of 5-FU factors was detected: orotate phosphoribosyltransferase: differentiated cases (P = 0.0137), lower T factor (P = 0.0411); dihydropyrimidine dehydrogenase: nerve invasion (P = 0.0188), lymph node recurrence (P = 0.0253); TS, positive N factor (P = 0.0061).

CONCLUSIONS

The expression of TS provides an alternative source of substrate for DNA synthesis and positively correlates with GEM resistance and shortened patient survival.

Impact of S-1 on the survival of patients with advanced pancreatic cancer

OBJECTIVE

The aim of this study was to investigate the effect of S-1 on the prognosis of advanced pancreatic cancer.

METHODS

In total, 112 patients with pancreatic cancer who received chemotherapy between April 2001 and April 2007 were divided into 2 groups: PreS-1 (53 patients who started chemotherapy before January 2005) and PostS-1 (59 patients who started chemotherapy after February 2005, the time of S-1 introduction). Patient characteristics and clinical outcomes were compared, and prognostic factors were analyzed.

RESULTS

Patient characteristics did not significantly differ between the 2 groups. S-1 was administered as a second-line monotherapy in 5.7% of the PreS-1 group and combined with gemcitabine as a first-line therapy in 27.1% or as second-line monotherapy in 23.7% in the PostS-1 group. Both progression-free survival and overall survival improved after introduction of S-1 (median progression-free survival, 4.4 and 5.3 months; P = 0.043; median overall survival, 9.5 and 13.1 months; P = 0.048 in PreS-1 and PostS-1 groups, respectively). Multivariate analysis revealed that the PostS-1 group (hazards ratio, 0.52; P = 0.003), performance status, and carcinoembryonic antigen were significant prognostic factors for survival.

CONCLUSIONS

Introduction of S-1 may improve the prognosis of Japanese patients with advanced pancreatic cancer.

A multi-institution phase II study of gemcitabine/S-1 combination chemotherapy for patients with advanced biliary tract cancer

PURPOSE

We aimed to evaluate the efficacy and safety of gemcitabine/S-1 combination chemotherapy for the treatment of patients with advanced biliary tract cancer.

METHODS

Patients with histologically or cytologically confirmed unresectable or recurrent biliary tract cancer were eligible for inclusion. The primary endpoint was overall survival. Gemcitabine was administered intravenously at a dose of 1,000 mg/m(2) over 30 min on days 1 and 8, and oral S-1 was administered daily at a dose of 60 mg/m(2) on days 1-14. This schedule was repeated every 3 weeks until disease progression or patient refusal.

RESULTS

Twenty-five patients were enrolled between October 2007 and January 2009. Eleven patients (44%) had extrahepatic bile duct cancer, 5 (20%) had intrahepatic bile duct cancer, 8 had gallbladder cancer (32%), and 1 (4%) had ampulla of Vater cancer. The median overall survival time was 12.7 months (95% CI, 8.4-23.5 months), and the 1-year survival rate was 52.0% (95% CI, 31.2-69.2%). Of the 23 patients with evaluable target regions, seven patients experienced a partial response, and an overall response rate was 30.4%. The following grade 3-4 hematological toxicities occurred: neutropenia (56%), leukopenia (24%), anemia (8%) and thrombocytopenia (4%). In spite of the high incidence of grade 3-4 neutropenia, no patients developed febrile neutropenia in the present study. The major grade 3-4 non-hematological toxicities were fatigue (8%), anorexia (8%) and diarrhea (4%).

CONCLUSIONS

Gemcitabine/S-1 combination chemotherapy offered a promising survival benefit with acceptable toxicity in patients with advanced biliary tract cancer.

Multicenter, phase II study of gemcitabine and S-1 combination chemotherapy in patients with advanced biliary tract cancer

PURPOSE

To evaluate the efficacy and safety of gemcitabine and S-1 combination chemotherapy in patients with advanced biliary tract cancer.

METHODS

Patients with a measurable lesion and no previous history of chemotherapy or radiotherapy were enrolled. Gemcitabine was administered intravenously at a dose of 1,000 mg/m(2) over 30 min on day 1 and 15, repeated every 4 weeks. S-1 was administered orally at a dose of 40 mg/m(2) b.i.d. on days 1-14. Tumor response was assessed every two cycles using Response Evaluation Criteria in Solid Tumors criteria.

RESULTS

As much as 35 patients were enrolled between December 2006 and July 2008; 14 patients (40%) with gallbladder cancer and 14 (40%) with intrahepatic cholangiocarcinoma were included and 7 patients (20%) had received previous surgical resection. The overall response rate was 34.3% and the overall disease control rate was 82.9%. The median overall survival time was 11.6 months (95% CI, 7.3-15.6 months), and the median time to progression was 5.9 months (95% CI, 4.0-7.7 months). The grade 3/4 toxicities were leucopenia (23%), neutropenia (34%), anemia (20%), thrombocytopenia (6%) and anorexia (3%).

CONCLUSIONS

Gemcitabine and S-1 combination chemotherapy has promising efficacy and good tolerability in patients with advanced biliary tract cancer.