Plasma concentrations of 5-fluorouracil and F-beta-alanine following oral administration of S-1, a dihydropyrimidine dehydrogenase inhibitory fluoropyrimidine, as compared with protracted venous infusion of 5-fluorouracil

The puzzling clinical presentation of fluoropyrimidines cardiotoxicity

The cardiotoxicity of fluoropyrimidines (FP) [5-Fluorouracil and Capecitabine] is often reported as acute cardiac ischemia with rest typical angina, signs of ischemia at electrocardiogram (ECG), and ventricular kinetics abnormalities. However, silent ischemia, effort-related toxicity, and ventricular arrhythmias (VA) have been also described. The aim of this study is to report a consecutive series of 115 patients with FP cardiotoxicity observed in a single center both within clinical prospective studies and during the clinical routine. The clinical presentation widely varied as regards symptoms, ECG abnormalities, and clinical outcomes. We report also the strategies used to prevent cardiotoxicity in a subgroup of 35 patients who continued o rechallenged FP therapy after cardiotoxicity. In nearly half of the patients, the cardiotoxicity was triggered by physical effort. Typical angina was rare: the symptoms were absent in 51% of cases and were atypical in half of the other cases. ST-segment elevation and VA were the most frequent ECG abnormality; however, ST segment depression or negative T waves were the only abnormalities in 1/3 of the cases. Troponins essays were often within the normal limits, even in presence of extensive signs of ischemia. The most effective strategy to prevent cardiotoxicity at rechallenge was reducing FP dosage and avoiding physical effort. Anti-ischemic therapies were not always effective. Raltitrexed was a safe alternative to FP. Fluoropyrimidine cardiotoxicity shows a wide variety of clinical presentations in real life, from silent ischemia to atypical symptoms, acute coronary syndrome, left ventricular dysfunction (LVD), VA, or complete atrio-ventricular block. Physical effort is the trigger of cardiotoxicity in nearly half of the cases. The recognition of cardiotoxicity cannot rely on symptoms only but requires an active screening with ECG and stress test in selected cases.

Managing 5FU Cardiotoxicity in Colorectal Cancer Treatment

Fluorouracil (5FU) is the backbone chemotherapy agent in the treatment of colorectal cancer (CRC). Cardiotoxicity represents an uncommon but serious side effect of treatment with 5FU. Here, we review the current literature on 5FU-cardiotoxicity in the setting of CRC specifically, with a focus on data from the modern era of combination chemotherapy. Despite decades of study, there is little consensus on risk factors and biomarkers for 5FU-cardiotoxicity, nor how patients with CRC should be managed following a cardiotoxicity event. Given the elevated risk of recurrent cardiotoxicity on rechallenge, the use of alternative regimens that do not contain 5FU is a critical aspect of management. Data on the cardiotoxicity risk and efficacy of non-5FU regimens in CRC are therefore reviewed in detail.

The Efficacy and Adverse Events in Patients with Head and Neck Cancer Following Radiotherapy Combined with S-1 Therapy: A Meta-Analysis

This meta-analysis was conducted to assess the efficacy and adverse events associated with S-1 chemotherapy combined with radiotherapy for patients with head and neck cancer. The PubMed, Embase, and Cochrane Library databases were searched up to 10 February 2021. Eligible studies included clinical trials using S-1 chemotherapy combined with radiotherapy for head and neck cancer patients that measured tumor response, local control rate, overall survival, and grade 3/4 adverse events. A meta-analysis was performed using a random effects model. Twelve trials involving 378 patients met the selection criteria. The objective response and clinical benefit rate (complete/partial response and stable disease) of S-1 chemotherapy with radiotherapy were 86.3% (95% confidence interval (CI), 60.3-96.3) and 88.3% (95% CI, 70.1-96.1), respectively. The median 3-year local control rate, 3-year overall survival rate, and grade 3/4 adverse event rate were 84.0% (95% CI, 71.4-91.7), 69.6% (95% CI, 54.9-81.1), and 42.0% (95% CI, 36.2-48.0), respectively. S-1 combined with radiotherapy for patients with head and neck squamous cell carcinoma results in a good tumor response, favorable survival rate, and low toxicity. A prospective randomized, double-blind trial is required to assess the efficacy and safety of S-1 combined with radiotherapy to treat HNSCC.

Modeling chemotherapy induced neurotoxicity with human induced pluripotent stem cell (iPSC) -derived sensory neurons

Chemotherapy-induced peripheral neuropathy (CIPN) is a frequent, potentially irreversible adverse effect of cytotoxic chemotherapy often leading to a reduction or discontinuation of treatment which negatively impacts patients' prognosis. To date, however, neither predictive biomarkers nor preventive treatments for CIPN are available, which is partially due to a lack of suitable experimental models. We therefore aimed to evaluate whether sensory neurons derived from induced pluripotent stem cells (iPSC-DSN) can serve as human disease model system for CIPN. Treatment of iPSC-DSN for 24 h with the neurotoxic drugs paclitaxel, bortezomib, vincristine and cisplatin led to axonal blebbing and a dose dependent decline of cell viability in clinically relevant IC₅₀ ranges, which was not observed for the non-neurotoxic compounds doxorubicin and 5-fluorouracil. Paclitaxel treatment effects were less pronounced after 24 h but prominent when treatment was applied for 72 h. Global transcriptome analyses performed at 24 h, i.e. before paclitaxel-induced cell death occurred, revealed the differential expression of genes of neuronal injury, cellular stress response, and sterol pathways. We further evaluated if known neuroprotective strategies can be reproduced in iPSC-DSN and observed protective effects of lithium replicating findings from rodent dorsal root ganglia cells. Comparing sensory neurons derived from two different healthy donors, we found preliminary evidence that these cell lines react differentially to neurotoxic drugs as expected from the variable presentation of CIPN in patients. In conclusion, iPSC-DSN are a promising platform to study the pathogenesis of CIPN and to evaluate neuroprotective treatment strategies. In the future, the application of patient-specific iPSC-DSN could open new avenues for personalized medicine with individual risk prediction, choice of chemotherapeutic compounds and preventive treatments.

Metastatic colorectal cancer: Advances in the folate-fluoropyrimidine chemotherapy backbone

Notwithstanding recent treatment advances in metastatic colorectal cancer (mCRC), chemotherapy with a combination of a fluoropyrimidine and a folate agent, often 5-fluorouracil (5-FU) and leucovorin, remains the backbone of treatment regimens for the majority of patients with mCRC. This is despite a recent focus on molecular-targeted treatments and patient stratification according to mutational status or expression levels of specific genes. Intracellular folate concentration was discovered to be pivotal in the cytotoxic efficacy of 5-FU, paving the way to the current standard combination therapy approach. Subsequent discovery that systemic chemotherapy agents, such as irinotecan and oxaliplatin, can further increase the efficacy of 5-FU-based treatments led to the development of several combination chemotherapy regimens, including FOLFOX, FOLFIRI and FOLFOXIRI. Subsequent efforts to optimise 5-FU-based treatments have focused on 5-FU analogues, initially capecitabine and the combination drug tegafur/gimeracil/oteracil (S-1) and then TAS-102, which has recently been evaluated in phase 3 clinical trials for refractory colorectal cancer. Further approaches taken to improve the efficacy of 5-FU chemotherapy regimens have focused on optimising the route and dosing schedules and regulating folate metabolism. Pharmacokinetic variability caused by the requirement for metabolic conversion of leucovorin has been central to recent research, and the development of agents such as arfolitixorin which bypass the need for metabolic conversion remains promising for future therapeutic candidates. In this review, we summarise the evidence leading to the current treatment regimens employing 5-FU and leucovorin, focusing on recent approaches taken to optimise and refine treatments to improve clinical outcomes in patients with mCRC.

Fluoropyrimidine-induced cardiotoxicity

Cardio-oncology is a discipline based on early screening, monitoring, and treating chemotherapy-induced cardiotoxicity. There are many chemotherapeutics known for their cardiac toxic effects, including fluoropyrimidines. Fluoropyrimidine represents the cornerstone of many types of cancer and each year almost two million cancer patients undergo this treatment. Fluoropyrimidine-induced cardiotoxicity can be manifested in several forms, from angina pectoris to sudden death. This paper is a review of how the cardiotoxicity of fluoropyrimidines is presented, the mechanisms of its occurrence, its diagnosis, and management.

Small intestinal mucosal injury and its risk factors in patients with gastrointestinal cancer who developed complicated fluoropyrimidine-induced diarrhea

Background

Diarrhea is a common adverse event of fluoropyrimidine-based chemotherapy. However, limited data are available on the frequency and risk factors of complicated chemotherapy-induced diarrhea (CID) and small intestinal mucosal damage. In this current study, we aimed to determine the incidence of complicated CID and mucosal injury among patients with complicated CID receiving fluoropyrimidine via small bowel capsule endoscopy (CE) and determined baseline risk factors associated with complicated CID.

Methods

In total, 536 patients with advanced or recurrent gastrointestinal cancer who received fluoropyrimidine-based chemotherapy were retrospectively analyzed. Diarrhea was evaluated using the Common Terminology Criteria for Adverse Events version 4. Complicated CID was defined according to the American Society of Clinical Oncology guidelines. To evaluate small intestinal mucosal injury in patients with complicated CID, CE was performed. Multivariate analysis was performed to identify risk factors for complicated CID.

Results

Total number of 32 (6%) patients developed complicated CID. Complicating symptoms were noted in 25 (78%) patients, with cramping, vomiting, and sepsis being observed in 15 (60%), 8 (32%), and 3 (12%) patients, respectively. Among the 13 patients who underwent CE, 11 (85%) showed abnormal findings. Multivariate analysis revealed that oral fluoropyrimidine administration was a risk factor for complicated CID (odds ratio 2.95; 95% confidence interval 1.06–8.19).

Conclusions

Despite the relatively low incidence of complicated CID, mucosal injury of small intestine was common in patients with complicated fluoropyrimidine-induced diarrhea and oral fluoropyrimidine was an independent risk factor.

Impact of sex and histology on the therapeutic effects of fluoropyrimidines and oxaliplatin plus bevacizumab for patients with metastatic colorectal cancer in the SOFT trial

Mechanisms accounting for sex differences in the incidence of adverse events caused by fluoropyrimidine treatments, and histologic differences in efficacy are insufficiently understood. We determined differences between the sexes in terms of the safety of S-1 plus oxaliplatin (SOX)/bevacizumab-versus-l-leucovorin, 5-fluorouracil (5-FU) and oxaliplatin (FOLFOX)/bevacizumab, and the impact of histology on their therapeutic effects, in 512 unresectable metastatic colorectal cancer patients from the SOFT phase III study. Nausea (OR: 2.88, P < 0.001) and vomiting (OR: 3.04, P = 0.005) occurred more frequently in females than males treated with SOX/bevacizumab, while nausea (OR: 2.12, P = 0.006), vomiting (OR: 3.26, P = 0.004), leukopenia (OR: 2.61, P < 0.001), neutropenia (OR: 2.92, P < 0.001), and alopecia (OR: 4.13, P < 0.001) were higher in females on FOLFOX/bevacizumab. Mean relative dose intensities (RDIs) of S-1 during all cycles of SOX/bevacizumab were significantly lower in females (73.9%) than males (81.5%) (P < 0.001), while RDIs of continuous infusion of 5-FU in the FOLFOX/bevacizumab regimen were 75.0% in females and 80.5% in males (P = 0.005). No significant differences in efficacy with regard to overall survival (OS) and progression-free survival (PFS) were identified between the sexes for either SOX/bevacizumab or FOLFOX/bevacizumab treatment. Patients with poorly-differentiated adenocarcinoma had significantly worse OS (HR: 2.72, 95% CI: 1.67-4.44, P < 0.0001) and PFS (HR: 1.89, 95% CI: 1.18-3.02, P = 0.0079) than patients with well- or moderately-differentiated adenocarcinoma. Female patients experienced more frequent and severe adverse reactions to SOX/bevacizumab and FOLFOX/bevacizumab and a worse prognosis for poorly-differentiated adenocarcinoma were confirmed in this phase III study. This warrants further translational research to identify the responsible mechanisms.

Cardiotoxicities of 5-Fluorouracil and Other Fluoropyrimidines

OPINION STATEMENT

Fluoropyrimidine (FP) is used to treat a wide range of cancers; however, it is associated with drug-induced vascular toxicity, as well as angina pectoris and coronary spasm. FP has been administered for many years, although the incidence, mechanisms, and appropriate methods for managing its associated cardiovascular toxicities have not been clarified, and the management of these complications has not been standardized. This lack of evidence is not limited to FP. Many trials of anticancer agents have been conducted, excluding patients with heart diseases. Hence, there is a paucity of epidemiological data on cardiovascular adverse events caused by anticancer agents. There have been remarkable improvements in cancer treatment in recent years, with consequent improvements in prognosis. In this context, new cardiovascular toxicities related to new drugs have emerged. We are now compelled to respond to cardiovascular adverse events despite the lack of evidence regarding optimal management. The result has been establishment and rapid maturation of the new academic field of cardio-oncology. Despite the relative lack of evidence, we must review small pieces of evidence that have accumulated to date and make the utmost efforts to provide patients with effective evidence-based medical care. Simultaneously, we urgently need randomized clinical trials to build strong evidence.

Management of cytotoxic chemotherapy-induced hand-foot syndrome

Improvements in systemic cancer treatments have resulted in more patients surviving for prolonged periods of time on treatment. This has made treatment-related toxicity and quality of life concerns increasingly relevant. Hand-foot syndrome (HFS) is a common skin reaction to systemic therapy that should be anticipated with chemotherapeutic treatments such as pegylated liposomal doxorubicin, docetaxel, and fluoropyrimidines. In this review we discuss current knowledge of the diagnosis, incidence, pathogenesis, and management of hand-foot syndrome (HFS). Although HFS is not life threatening, it can cause significant discomfort and impairment of function, especially in elderly patients, and may seriously impact quality of life. The incidence of HFS is dependent on the chemotherapeutic drug used, the treatment schedule, and the median duration of treatment. Effective measures for prevention and treatment of HFS include systemic and topical treatments, dose reductions, and switching to other drugs in the same class that are associated with lower rates of HFS. These approaches allow patients to continue cancer treatment while reducing negative impacts on quality of life. Awareness and early recognition are important to ensure timely treatment and avoidance of dose reductions or treatment discontinuation. We provide useful recommendations to guide the management of HFS in clinical practice.

A Study of the S-1 or Capecitabine as First-line Regimen in Patients with Metastatic Colorectal Cancer: A Real World Study

Objectives: To compare the 2-year overall survival (OS) rate and safety between patients using S-1 and capecitabine in the first-treatment of metastatic colorectal cancer in the real clinical setting. Methods: In this retrospective cohort study, patients satisfying the following criteria were identified from 10 centers in China. The 2-year OS rate and safety were assessed. The propensity score matching (PSM) was used to control basic characteristics of the two groups to balance the processing bias and confoundings. Results: A total of 1367 patients were identified, 824 patients accepted capecitabine and 546 patients accepted S-1. After PSM, 533 eligible patients were included in each group without statistical significance in age, sex, BMI, KPS score and comorbidities. The 2-year OS rate between two groups was without significant statistical difference (61.9% vs. 62.9%, p=0.4295). The subgroup analysis showed that the 2-year OS rate had no significant difference between men and women, younger and older than 60 years old, different metastatic sites, different chemotherapy courses between S-1 and capecitabine groups. The hematological adverse events were all without statistical difference between two groups, but the incidence of diarrhea (16.4% vs. 23.6%, p=0.0018) and hand-foot syndrome (28.7% vs. 46.7%, p<0.001) in S-1 group were lower than those in the capecitabine group. Conclusions: Compared to capecitabine, S-1 had a similar 2-year OS rate but had a lower incidence of adverse events in the real clinical setting. So, S-1 could be a good choice in the first-treatment of patients with metastatic colorectal cancer in China.

The Main Metabolites of Fluorouracil + Adriamycin + Cyclophosphamide (FAC) Are Not Major Contributors to FAC Toxicity in H9c2 Cardiac Differentiated Cells

In the clinical practice, the combination of 5-fluorouracil (5-FU) + Adriamycin (also known as doxorubicin, DOX) + cyclophosphamide (CYA) (known as FAC) is used to treat breast cancer. The FAC therapy, however, carries some serious risks, namely potential cardiotoxic effects, although the mechanisms are still unclear. In the present study, the role of the main metabolites regarding FAC-induced cardiotoxicity was assessed at clinical relevant concentrations. Seven-day differentiated H9c2 cells were exposed for 48 h to the main metabolites of FAC, namely the metabolite of 5-FU, α-fluoro-β-alanine (FBAL, 50 or 100 μM), of DOX, doxorubicinol (DOXOL, 0.2 or 1 μM), and of CYA, acrolein (ACRO, 1 or 10 μM), as well as to their combination. The parent drugs (5-FU 50 μM, DOX 1 μM, and CYA 50 μM) were also tested isolated or in combination with the metabolites. Putative cytotoxicity was evaluated through phase contrast microscopy, Hoechst staining, membrane mitochondrial potential, and by two cytotoxicity assays: the reduction of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and the neutral red (NR) lysosomal incorporation. The metabolite DOXOL was more toxic than FBAL and ACRO in the MTT and NR assays. When in combination, neither FBAL nor ACRO increased DOXOL-induced cytotoxicity. No nuclear condensation was observed for any of the tested combinations; however, a significant mitochondrial potential depolarization after FBAL 100 μM + DOXOL 1 μM + ACRO 10 μM or FBAL 100 μM + DOXOL 1 μM exposure was seen at 48 h. When tested alone DOX 1 μM was more cytotoxic than all the parent drugs and metabolites in both the cytotoxicity assays performed. These results demonstrated that DOXOL was the most toxic of all the metabolites tested; nonetheless, the metabolites do not seem to be the major contributors to FAC-induced cardiotoxicity in this cardiac model.

Cardiotoxicity of 5-fluorouracil and capecitabine in Chinese patients: a prospective study

Background

5-Fluorouracil (5-FU) and capecitabine-associated cardiotoxicity ranging from asymptomatic electrocardiography (ECG) abnormalities to severe myocardial infarction has been reported in a number of studies, but such cardiotoxicity in Chinese patients with malignant diseases has not been investigated to date. In the present study, we aimed to prospectively evaluate the incidence rates and clinical manifestations of 5-FU- and capecitabine-associated cardiotoxicity in cancer patients recruited from multiple centers in China.

Methods

Among the 527 patients who completed the study, 196 received 5-FU-based chemotherapy and 331 received capecitabine-based chemotherapy as either first-line or adjuvant therapy. Adverse events were reported during the treatment and up to 28 days of follow-up. Outcome measures included ECG, myocardial enzymes, cardiac troponin, brain natriuretic peptide and echocardiography. Univariate analysis and logistic regression were performed for subgroup analysis and identification of significant independent variables that are associated with cardiotoxicity of both agents.

Results

In total, 161 of 527 patients (30.6%) experienced cardiotoxicity. The incidence rate of cardiotoxicity was 33.8% (112/331) in the capecitabine group, which was significantly higher than the rate of 25% (49/196) in the 5-FU group (P = 0.0042). 110/527 patients (20.9%) suffered arrhythmia, 105/527 (19.9%) developed ischemic changes, while only 20/527 patients (3.8%) presented heart failure and 6/527 patients (1.1%) had myocardial infarction. Pre-existing cardiac disease, hypertension, capecitabine-based chemotherapy and duration of treatment were identified as significant risk factors associated with cardiotoxicity. The odds ratio were 15.7 (prior history of cardiac disease versus no history), 1.86 (capecitabine versus 5-FU), 1.06 (5–8 versus 1–4 chemotherapy cycles) and 1.58 (hypertension versus no hypertension), respectively.

Conclusions

Cardiotoxicity induced by fluoropyrimidines in the Chinese population may be underestimated in clinical practice. Close monitoring of patients is recommended, especially for those patients at high risk for cardiotoxicity. Possible risk factors are duration of treatment, capecitabine-based chemotherapy, pre-existing cardiac diseases and hypertension.

Trial registration This study was initiated on January 22, 2014 and has been retrospectively registered with the registration number ChiCTR1800015434

Concurrent chemoradiotherapy for cervical esophageal squamous cell carcinoma: treatment results from a prospective observational study

A prospective observational study was performed to evaluate the results of treatment with concurrent chemoradiotherapy (CCRT) in patients with cervical esophageal squamous cell carcinoma (CESCC). Patients had CESCC, no distant metastasis, were 18-75 years old, and had PS 0-2. Radiotherapy (RT) was administered as either three-dimensional conformal radiation therapy (3D-CRT) or intensity-modulated radiation therapy (IMRT) with a total dose of 60 Gy/30 fractions. All patients were treated with platinum-based doublet concurrent chemotherapeutic regimens. CCRT was followed by 2-3 cycles of consolidation chemotherapy. The endpoints were overall survival (OS), progression-free survival (PFS), toxicities, and failure patterns. Ninety-two patients were enrolled from March 2007 to July 2014. The median follow-up time was 34 months. For all patients, the 3-year OS was 49.8% (median OS: 36 months, 95% CI: 24.963-47.051), and the 3-year PFS was 42.1%, (median PFS: 25 months, 95% CI: 17.097-32.903). Treatment failures occurred in 54 patients, including 30 cases (32.6%) with locoregional failure alone, 14 cases (15.2%) with distant metastasis alone, and 10 cases (10.9%) with both locoregional failure and distant metastasis. There were 51 (55.4%) and 3 cases (3.3%) of grade 3 and grade 5 radiation esophagitis, respectively. One patient (1%) had grade 5 laryngeal edema. Overall, CCRT has tolerable acute toxicities, and this regimen is an option for the treatment of patients with CESCC.

Notch pathway inhibition targets chemoresistant insulinoma cancer stem cells

Insulinomas (INS) are the most common neuroendocrine pancreatic tumours in humans and dogs. The long-term prognosis for malignant INS is still poor due to a low success rate of the current treatment modalities, particularly chemotherapy. A better understanding of the molecular processes underlying the development and progression of INS is required to develop novel targeted therapies. Cancer stem cells (CSCs) are thought to be critical for the engraftment and chemoresistance of many tumours, including INS. This study was aimed to characterise and target INS CSCs in order to develop novel targeted therapies. Highly invasive and tumourigenic human and canine INS CSC-like cells were successfully isolated. These cells expressed stem cell markers (OCT4, SOX9, SOX2, CD133 and CD34), exhibited greater resistance to 5-fluorouracil (5-FU) and demonstrated a more invasive and tumourigenic phenotype in vivo compared to bulk INS cells. Here, we demonstrated that Notch-signalling-related genes (NOTCH2 and HES1) were overexpressed in INS CSC-like cells. Protein analysis showed an active NOTCH2-HES1 signalling in INS cell lines, especially in cells resistant to 5-FU. Inhibition of the Notch pathway, using a gamma secretase inhibitor (GSI), enhanced the sensitivity of INS CSC-like cells to 5-FU. When used in combination GSI and 5-FU, the clonogenicity in vitro and the tumourigenicity in vivo of INS CSC-like cells were significantly reduced. These findings suggested that the combined strategy of Notch signalling inhibition and 5-FU synergistically attenuated enriched INS CSC populations, providing a rationale for future therapeutic exploitation.

Comparative study of cisplatin-based definitive concurrent chemoradiotherapy with S-1 versus paclitaxel for unresectable locally advanced esophageal squamous cell carcinoma

This study compared the efficiency and safety of definitive concurrent chemoradiotherapy (CCRT) using Paclitaxel plus Cisplatin (TP) versus S-1 plus Cisplatin (CS) in unresectable locally advanced esophageal squamous cell carcinoma (LAESCC). Between January 2009 and December 2013, 203 LAESCC patients were retrospectively reviewed. We performed a propensity score matching analysis; 41 patients treated with the CS regimen were matched 1:1 to patients who received the TP regimen. Patient- and disease-related characteristics were well-balanced between the two groups. The CS group showed significantly better treatment compliance (90.2% vs. 70.7%, P = 0.026) and less hospital stay (48 days vs 49 days, P = 0.025) over the TP group during the CCRT course. The complete response rate was comparable between the two groups (51.2% vs. 48.8%, P = 0.825). The 1- and 3-year overall survival (OS) rates in the TP group were 63.4% and 32.4% compared to 62.8% and 32.1% in the CS group, respectively (P = 0.796). The 1- and 3-year progression-free survival (PFS) rates in the TP group were 51.2% and 24.9%, compared to 53.6% and 18.9% in the CS group, respectively (P = 0.630). The incidence of severe and total neutropenia in the TP group was significantly higher compared to the CS group (P = 0.011 and 0.046, respectively). Multivariate analysis revealed that T stage and the complete response rate were strong prognostic factors associated with OS and PFS. In conclusion, both treatment regimens yielded satisfactory survival outcomes, but the CS regimen could significantly improve treatment compliance, reduce hematological toxicities and lengths of hospital stay. Future prospective studies in large cohorts are highly warranted to confirm the findings in our report.

New Perspectives in the Treatment of Advanced Gastric Cancer: S-1 as a Novel Oral 5-FU Therapy in Combination with Cisplatin

Oral fluoropyrimidines have been available for more than 10 years. Capecitabine is well established in treating solid tumors in Europe. S-1 (Teysuno®), an oral formulation containing the 5-fluorouracil (5-FU) prodrug tegafur and the two enzyme modulators gimeracil and oteracil, has not been available in non-Asia countries until recently. In Japan, S-1 in combination with cisplatin is the recommended first-line treatment in patients with gastric cancer. In Europe, the first trials with S-1 were disappointing due to high unacceptable incidences of adverse events. Pharmacokinetic studies showed differences in Asian and Caucasian patients; therefore, a new non-Asian study program was initiated, which led to the pivotal phase 3 trial First-Line Advanced Gastric Cancer Study (FLAGS). In FLAGS, 1,053 patients with advanced gastric cancer from 24 non-Asian countries were enrolled. S-1 plus cisplatin showed no overall survival (OS) benefit when compared to 5-FU plus cisplatin. The primary endpoint superior OS was not met but better tolerability was shown. A post hoc noninferiority OS and safety analysis showed that S-1 plus cisplatin has the same efficacy as 5-FU plus cisplatin but a more favorable safety profile. This led to the approval of S-1 in combination with cisplatin in gastric cancer in Europe in 2011. This article reviews the mode of action of S-1, pivotal study results from an EU point of view, and future perspectives.

A simultaneous determination method for 5-fluorouracil and its metabolites in human plasma with linear range adjusted by in-source collision-induced dissociation using hydrophilic interaction liquid chromatography-electrospray ionization-tandem mass spectrometry

We applied a new technique for quantitative linear range shift using in-source collision-induced dissociation (CID) to complex biological fluids to demonstrate its utility. The technique was used in a simultaneous quantitative determination method of 5-fluorouracil (5-FU), an anticancer drug for various solid tumors, and its metabolites in human plasma by liquid chromatography-electrospray ionization-tandem mass spectrometry (LC/ESI-MS/MS). To control adverse effects after administration of 5-FU, it is important to monitor the plasma concentration of 5-FU and its metabolites; however, no simultaneous determination method has yet been reported because of vastly different physical and chemical properties of compounds. We developed a new analytical method for simultaneously determining 5-FU and its metabolites in human plasma by LC/ESI-MS/MS coupled with the technique for quantitative linear range shift using in-source CID. Hydrophilic interaction liquid chromatography using a stationary phase with zwitterionic functional groups, phosphorylcholine, was suitable for separation of 5-FU from its nucleoside and interfering endogenous materials. The addition of glycerin into acetonitrile-rich eluent after LC separation improved the ESI-MS response of high polar analytes. Based on the validation results, linear range shifts by in-source CID is the reliable technique even with complex biological samples such as plasma. Copyright © 2016 John Wiley & Sons Ltd.

A phase I dose escalation study of S-1 with concurrent radiotherapy in elderly patients with esophageal cancer

BACKGROUND

Concurrent chemoradiotherapy (CRT) with 5-fluorouracil (5-FU) and cisplatin (CDDP) are often associated with significant incidence of toxic effects in elderly patients with esophageal cancer. This phase I trial was designed to determine the maximum tolerated dose (MTD) and dose-limiting toxicity (DLT) of S-1, an oral 5-FU derivative, when given with radiotherapy in elderly patients.

METHODS

Patients who were age of 70 years or older with histologically confirmed esophageal cancer, and had an Eastern Cooperative Oncology Group (ECOG) score of 0-2 were eligible for this study. Radiotherapy was administered in 1.8 Gy fractions 5 times weekly to a total dose of 54 Gy. S-1 was administered on days 1-14 and 29-42 at the following dosages: 60, 70, and 80 mg/m(2)/day.

TRIAL REGISTRATION

NCT01175447 (ClinicalTrials.gov).

RESULTS

Twelve previously untreated patients were enrolled in this study. No grade 3 or 4 toxicity was observed in six patients treated at the 60 and 70 mg/m(2) dose levels. DLT was observed in four of six patients treated at the 80 mg/m(2) dose level. Two patients developed grade 3 esophagitis, one patient developed grade 3 esophagitis and pneumonitis, and one patient developed grade 3 thrombocytopaenia. Endoscopic complete response (CR) was observed in eight patients (66.7%). The median progression free survival (PFS) was 20 months and median overall survival was 29 months.

CONCLUSIONS

The MTD of S-1 was 80 mg/m(2), and the recommended dose (RD) for phase II studies was 70 mg/m(2). This regimen was well tolerated and active in elderly patients with esophageal cancer, meriting further investigation in phase II studies.

The SOFT trial: a Phase III study of the dihydropyrimidine dehydrogenase inhibitory fluoropyrimidine S-1 and oxaliplatin (SOX) plus bevacizumab as first-line chemotherapy for metastatic colorectal cancer

ABSTRACT 

A combination of oxaliplatin, leucovorin and 5-fluorouracil (FOLFOX) plus bevacizumab has been widely used for the first-line chemotherapy of metastatic colorectal cancer (mCRC). S-1 is an oral fluoropyrimidine preparation that combines tegafur, a prodrug of 5-fluorouracil, with two modulators. Several studies of combination chemotherapy with oxaliplatin plus S-1 (SOX) conducted in Asia have reported promising efficacy and safety in patients with mCRC, suggesting the potential to replace mFOLFOX6. The SOFT trial (JapicCTI-090699) was a randomized Phase III trial designed to evaluate the noninferiority of SOX plus bevacizumab to mFOLFOX6 plus bevacizumab in patients with mCRC. This review summarizes the drug concept of S-1 and the results of clinical trials of S-1 and SOX in CRC and presents an overview of the SOFT trial.

A Phase II Trial of Combined Chemotherapy with Oral S-1 and 24-Hour Infusions of Irinotecan plus Bevacizumab in Patients with Metastatic Colorectal Cancer

OBJECTIVES

Protracted low-dose infusion of irinotecan has been suggested to enhance antitumor activity. A phase II study was conducted to evaluate the safety and efficacy of oral S-1 combined with 24-hour infusion of irinotecan and intravenous bevacizumab for metastatic colorectal cancer (MCRC).

METHODS

The subjects were 79 patients with MCRC; 57 were chemotherapy naïve. Irinotecan (125 mg/m(2)) was administered as a 24-hour infusion on days 1 and 15, S-1 (80 mg/m(2)) was administered orally on days 1-14, and bevacizumab (5.0 mg/kg) was given on days 1 and 15. The treatment was repeated every 4 weeks.

RESULTS

Median follow-up was 20.0 months, and the mean number of cycles was 7. The overall response rate was 79.7% (95% CI, 69.2-88.0), 86.0% (95% CI, 74.2-93.7) for first-line and 63.6% (95% CI, 40.7-82.8) for second-line treatment. The median progression-free survival was 16.4 months (95% CI, 13.9-21.0) for first-line and 9.4 months (95% CI, 4.9-16.5) for second-line treatment. The median overall survival was not reached. Grade 3-4 toxicities were neutropenia (43%), leukopenia (20.3%), anorexia (19.0%), and diarrhea (10.1%). Toxicity was tolerable.

CONCLUSIONS

Combination chemotherapy with oral S-1 and biweekly 24-hour infusions of irinotecan plus bevacizumab appears to be highly active and well tolerated both as first-line and second-line chemotherapy for MCRC.

Phase II study of concurrent chemoradiotherapy with S-1 in patients with stage II (T2N0M0) squamous cell carcinoma of the Pharynx or Larynx

OBJECTIVE

The goals of treatment for head and neck cancer are cure and organ-function preservation. For organ preservation, primary treatment via radiotherapy alone is thought to be insufficient for Stage II squamous cell carcinoma of the larynx, oropharynx or hypopharynx. The objective of the present study was to investigate the efficacy and safety of concurrent chemoradiotherapy with S-1 for patients with Stage II squamous cell carcinoma of the pharynx or larynx for primary organ preservation.

METHODS

Previously untreated patients with Stage II squamous cell carcinoma of the larynx, oropharynx or hypopharynx received three courses of S-1 (40 or 50 mg twice a day; 2 weeks of administration followed by 1 week of rest every 3 weeks) during conventional radiotherapy (a single daily fraction of 1.8 Gy) to a total dose of 70.2 Gy. The primary endpoint was the local control rate at 3 years.

RESULTS

From August 2009 to October 2012, 37 patients were evaluated for the study. The overall response rate was 100%. The 3-year local control rate was 89.0% (95% confidence interval, 78.9-99.2%), and the 3-year overall survival rate was 97.2% (95% confidence interval, 91.8-100%). Mucositis and dermatitis in the radiation field were the most common acute adverse events observed. The rates of Grade 3 mucositis and dermatitis were 27 and 35%, respectively. No patients experienced Grade 4 acute adverse events. The treatment completion rate was 89.2%.

CONCLUSION

Concurrent chemoradiotherapy with S-1 was safe and effective in improving local control for Stage II squamous cell carcinoma of the pharynx or larynx.

Thymidine phosphorylase mRNA expression may be a predictor of response to post-operative adjuvant chemotherapy with S-1 in patients with stage III colorectal cancer

The aim of the present study was to investigate markers in surgically resected specimens of colorectal cancer that can be used to predict the response to chemotherapy. The mRNA expression levels of enzymes involved in 5-fluorouracil (5-FU) metabolism and folate metabolism were measured in formalin-fixed, paraffin-embedded tumor sections obtained from the primary tumors of 54 patients with resected stage II or III colorectal cancer who received S-1 for one year. The 5-FU metabolizing enzymes studied were thymidylate synthase, dihydropyrimidine dehydrogenase and thymidine phosphorylase (TP). The folate metabolizing enzymes studied were folypolyglutamate synthetase, γ-glutamyl hydrolase and dihydrofolate reductase. The associations between the mRNA expression levels of these enzymes and clinical variables were investigated. Tumors were classified as exhibiting high or low expression as compared with the median mRNA expression level of each metabolizing enzyme defined as the cutoff value. The associations between the high and low expression levels of each enzyme and disease-free survival (DFS) were analyzed with the use of Kaplan-Meier curves and the log-rank test. DFS was not significantly associated with the relative mRNA expression level of any metabolizing enzyme in the study group as a whole, but there was a trend toward longer DFS in patients with high TP expression (P=0.066). In patients with stage III colorectal cancer, high TP expression was associated with significantly improved outcomes compared with low TP expression (P=0.039). These results indicate that the mRNA expression of TP, a metabolizing enzyme of 5-FU, is a significant predictor of response to post-operative chemotherapy with S-1 in patients with stage III colorectal cancer.

Neoadjuvant chemoradiation therapy using concurrent S-1 and irinotecan in rectal cancer: impact on long-term clinical outcomes and prognostic factors

PURPOSE

To assess the long-term outcomes of patients with rectal cancer who received neoadjuvant chemoradiation therapy (NCRT) with concurrent S-1 and irinotecan (S-1/irinotecan) therapy.

METHODS AND MATERIALS

The study group consisted of 115 patients with clinical stage T3 or T4 rectal cancer. Patients received pelvic radiation therapy (45 Gy) plus concurrent oral S-1/irinotecan. The median follow-up was 60 months.

RESULTS

Grade 3 adverse effects occurred in 7 patients (6%), and the completion rate of NCRT was 87%. All 115 patients (100%) were able to undergo R0 surgical resection. Twenty-eight patients (24%) had a pathological complete response (ypCR). At 60 months, the local recurrence-free survival was 93%, disease-free survival (DFS) was 79%, and overall survival (OS) was 80%. On multivariate analysis with a proportional hazards model, ypN2 was the only independent prognostic factor for DFS (P=.0019) and OS (P=.0064) in the study group as a whole. Multivariate analysis was additionally performed for the subgroup of 106 patients with ypN0/1 disease, who had a DFS rate of 85.3%. Both ypT (P=.0065) and tumor location (P=.003) were independent predictors of DFS. A combination of these factors was very strongly related to high risk of recurrence (P<.0001), which occurred most commonly in the lung.

CONCLUSIONS

NCRT with concurrent S-1/irinotecan produced high response rates and excellent long-term survival, with acceptable adverse effects in patients with rectal cancer. ypN2 is a strong predictor of dismal outcomes, and a combination of ypT and tumor location can identify high-risk patients among those with ypN0/1 disease.

A phase I study of sorafenib in combination with S-1 plus cisplatin in patients with advanced gastric cancer

BACKGROUND

Sorafenib inhibits several receptor tyrosine kinases involved in tumor progression and angiogenesis. S-1, an oral fluorouracil antitumor drug, plus cisplatin (CDDP) is the standard regimen for advanced gastric adenocarcinoma (AGC) in Japan. The purpose of this phase I study was to evaluate the safety, pharmacokinetics, and preliminary efficacy of sorafenib in combination with S-1 plus CDDP.

METHODS

Patients with histologically confirmed previously untreated AGC were evaluated for eligibility and treated with sorafenib (400 mg bid, days 1-35), S-1 (40 mg/m(2) bid, days 1-21), and CDDP (60 mg/m(2), day 8). Treatment was continued until disease progression or unacceptable toxicity. Pharmacokinetics for sorafenib, 5-FU, and CDDP were investigated in cycle 1.

RESULTS

Thirteen patients were enrolled and received at least one dose of the study treatment. No specific or serious adverse event was newly reported in this study. Five patients had partial response and 8 had stable disease as the best response. Pharmacokinetic analysis showed no significant differences in the exposures of sorafenib when administered alone or in combination with S-1 and CDDP.

CONCLUSIONS

The present phase I study demonstrates the acceptable toxicity and preliminary efficacy of combined treatment with S-1, CDDP, and sorafenib.

Optimization of cancer chemotherapy on the basis of pharmacokinetics and pharmacodynamics: from patients enrolled in clinical trials to those in the 'real world'

  Cytotoxic anticancer drugs are the most challenging therapeutic agents among all medicines with relatively narrow efficacy profiles. Therefore, medical oncologists have to practically manage the risk of severe toxic effects to optimize treatment outcomes. Dose and treatment-schedule recommendations for cytotoxic anticancer agents are determined on the basis of clinical trials. Patients enrolled in clinical trials are those likely to receive the drug in clinical practice, excluding those with conditions such as organ dysfunction, obesity, advanced age, or comorbidity. On the other hand, the 'real world' includes large numbers of such patients who do not meet the eligibility criteria of clinical trials. However, there is a paucity of data from sufficiently powered pharmacokinetic and pharmacodynamic studies to support dosage recommendations in such patients. Consequently, dose levels and treatment schedules for chemotherapy in these subjects are somewhat arbitrary and not evidence-based. Pharmacokinetic and pharmacodynamic studies of patients in the 'real world' are needed to address this issue. In this review article, we describe general aspects of clinical pharmacology in cancer patients enrolled in clinical trials and those in the 'real world,' and introduce recent findings regarding the pharmacokinetic and pharmacodynamic properties of irinotecan and S-1 in 'real world' cancer patients.

Abrogation of the accelerated blood clearance phenomenon by SOXL regimen: promise for clinical application

We recently proposed an S-1 combined with oxaliplatin (SOXL) regimen, a combination treatment consisting of oral metronomic S-1 dosing and intravenous administration of oxaliplatin (l-OHP) containing PEGylated liposomes, which showed potent antitumor activity in vivo. PEGylated liposomes induce what is referred to as the "accelerated blood clearance (ABC) phenomenon" upon repeated administration and consequently lose their long-circulating characteristics. This phenomenon seems to pose an impediment for the clinical application and use of PEGylated liposomal formulations. In the present study, l-OHP-containing PEGylated liposomes in the SOXL regimen significantly attenuated the ABC phenomenon in a dose-dependent manner through suppression of the anti-PEG IgM response, which allowed an enhanced hepatic uptake of subsequently injected test PEGylated liposomes. In tumor-bearing mice, the abrogation of the ABC phenomenon restored intratumor accumulation of subsequently injected PEGylated liposomes. Consequently, the therapeutic efficacy of the SOXL regimen over the combination of the free form of the drugs was credited not only with the selective delivery of drugs to the tumor tissue but also with ensuring an adequate accumulation of subsequent doses within the tumor tissue. The SOXL regimen we proposed may hold promise as a safe and effective treatment regimen for advanced colorectal cancer.

Alternative treatment options in colorectal cancer patients with 5-fluorouracil- or capecitabine-induced cardiotoxicity

Most chemotherapy regimens in colorectal cancer treatment are 5-fluorouracil (5-FU)/leucovorin or capecitabine-based. Cardiotoxicity is a less common but potentially lethal complication of 5-FU or capecitabine treatment, and some physicians might be unfamiliar with treatment alternatives. Rechallenging should be avoided because it carries a high risk of recurrence of the cardiac symptoms and prophylactic treatment is not always protective. Possible alternative treatment options to be considered are to replace the oral capecitabine or intravenous 5-FU by a 5-FU bolus regimen, by uracil-tegafur or tegafur/gimeracil/oteracil, both oral fluoropyrimidines combining a 5-FU prodrug with a dihydropyrimidine dehydrogenase (DPD) inhibitor, or by raltitrexed, a thymidilate synthase inhibitor whose metabolism is independent of DPD. Patients with advanced colorectal cancer and fluoropyrimidine-induced cardiotoxicity can be treated with other non-fluoropyrimidine related chemotherapy, either as a single agent, combined, or in combination with biological agents. In this report we discuss the different alternative treatment options.

Feasibility study of S-1 adjuvant chemotherapy in patients with colorectal cancer

BACKGROUND

We evaluated the safety, efficacy, and compliance of 1-year treatment with S-1 in patients with stage II/III resectable colorectal cancer.

METHODS

S-1 was administered orally in two divided doses daily. The dose was assigned according to body surface area (BSA) as follows: BSA <1.25 m(2), 80 mg/day; BSA ≥1.25 to <1.5 m(2), 100 mg/day; and BSA ≥1.5 m(2), 120 mg/day. S-1 was given for 28 consecutive days, followed by a 14-day rest. The study objects were the rate of completion of treatment as planned at 1 year, the ratio of the actually administered dose to the planned dose at 1 year, and the total number of days of treatment.

RESULTS

At 1 year, the rate of completion of treatment as planned was 77.7 % (42/54 patients), and the ratio of the actually administered dose to the planned dose was 82.9 %. The mean and median total numbers of days of treatment were 209 and 252, respectively. Grade 3 or higher toxicity (watery eyes) occurred in only 1 patient.

CONCLUSION

S-1 adjuvant chemotherapy had acceptable compliance, safety, and efficacy in patients with colorectal cancer. S-1 adjuvant chemotherapy is considered a possible standard treatment regimen for colorectal cancer.

Therapeutic effects of combined oxaliplatin and S-1 in older patients with advanced gastric cardiac adenocarcinoma

AIM: To evaluate the effects and safety of combination chemotherapy with oxaliplatin (L-OHP) and S-1 (SOX regimen) in older patients with advanced gastric cardiac adenocarcinoma (GCA).

METHODS: Seventy patients with advanced GCA were classified according to age into an older group (≥ 75 years) and a control group (< 75 years). The SOX regimen was administered to the two groups as follows: S-1 (40 mg/m² po bid) on days 1 to 14 followed by a 7-d off period, plus L-OHP (65 mg/m² iv) for 2 h on days 1 and 8 of a 21-d cycle. This regimen was repeated for four to six cycles. Response and swallow statuses were evaluated after two cycles (6 wk). Effects and toxicity were evaluated four weeks after chemotherapy was completed.

RESULTS: The response rate was 65.6% (21/32) in the older group and 68.4% (26/38) in the control group (χ² = 0.062 and P = 0.804). Improvement in swallowing was 78.1% (25/32) in the older group and 76.3% (29/38) in the control group (χ² = 0.032 and P = 0.857). Efficacy was 68.8% (22/32) in the older group and 65.8% (25/38) in the control group (χ² = 0.069 and P = 0.793). Toxicities were reversible and similar in both groups (P > 0.05).

CONCLUSION: The SOX regimen is an effective, safe and well-tolerated regimen for older patients with advanced GCA.

Consecutive daily low-dose S-1 adjuvant chemotherapy after radical treatment for squamous cell carcinoma in head and neck cancer

CONCLUSION

Consecutive daily low-dose S-1 therapy was less toxic and its efficacy was not inferior to the conventional administration schedule. Consecutive daily low-dose S-1 chemotherapy appears to be a treatment option for patients in whom it is difficult to continue the conventional administration schedule of S-1 due to adverse events.

OBJECTIVE

To evaluate the safety and efficacy of consecutive daily low-dose S-1 therapy in an adjuvant setting.

METHODS

This study investigated 52 patients with absence of local residual tumor, lymph node metastasis or distant metastasis after radical treatment for advanced head and neck squamous cell carcinoma. After receiving informed consent from patients, half of the usual dose of S-1 was administered daily for 2 years. The safety, feasibility, and efficacy of this approach were evaluated.

RESULTS

Hematologic toxicity was seen in 51 of 52 patients (98.1%), but grade 3 hematologic toxicity was found in only 2 patients (3.8%). Nonhematologic toxicity was observed in 15 patients (28.8%) and all were grade 1. Forty-three patients (82.7%) were able to complete the chemotherapy for 2 years without dose reduction. The 3-year disease-free survival rate and 3-year survival rate were 82.6% and 94.0%, respectively.

Phase II study of oral S-1 with irinotecan and bevacizumab (SIRB) as first-line therapy for patients with metastatic colorectal cancer

Fluorouracil (5-FU) plus irinotecan combined with bevacizumab has significant activity in metastatic colorectal cancer (mCRC), but S-1 has become a substitute for continuous infusion of 5-FU and has a very low incidence of hand-foot syndrome. With the S-1 plus irinotecan regimen (SIR), the response rate was 62.5%, and the progression-free survival was 8.0 months. We report here on an update of efficacy and safety of the SIR plus bevacizumab (SIRB) regimen as first line treatment for mCRC patients. Fifty-one eligible patients with histologically confirmed advanced or recurrent colorectal cancer received this treatment. S-1 was administered orally on days 1-14 of a 21-day cycle. Patients were assigned on the basis of body surface area (BSA) to receive one of the following oral doses twice daily: 40 mg, 50 mg, or 60 mg. Irinotecan (150 mg/m(2)) plus bevacizumab (7.5 mg/kg) were administered by intravenous infusion on day 1. Safety analysis identified a grade 3/4 neutropenia rate of 26%. Other grade 3/4 toxicities were diarrhea (8%), nausea (6%), vomiting (2%), and hypertension (8%). The response rate was 67% and the median progression-free survival time was 373 days. The SIRB regimen appears to be highly active and well tolerated as first-line treatment for mCRC.

Determination of eniluracil and 5-fluorouracil in human plasma by LC-MS/MS

BACKGROUND

5-fluorouracil (5-FU) has been one of the most widely used chemotherapeutic agents to treat various tumors, and eniluracil (5-ethynyluracil or EU) is being developed as a novel modulator of 5-FU.

RESULTS

A simple and sensitive LC-MS/MS method was developed for reliably quantifying both EU and 5-FU in human plasma. The method was validated for EU over a dynamic concentration range from 4.13 ng/ml (LOQ) to 1030 ng/ml and for 5-FU over a dynamic concentration range from 8.61 ng/ml (LOQ) to 1080 ng/ml. The analog, 5-bromouracil, was used as the internal standard for calibration curves and quantitation. Method validation has covered the scope of precision, accuracy, specificity, LOQ, linearity/range, freeze-thaw cycles, benchtop integrity/stability, storage stability, matrix effect, recoveries and so on, in accordance with US FDA bioanalytical method validation guidelines.

CONCLUSIONS

The validated method has shown good applicability for clinical studies and may be used for other clinical trials that involve measuring the concentration of EU and 5-FU simultaneously in human plasma and potentially in other similar biological matrices.

A multi-institutional phase II study of combination chemotherapy with S-1 plus cisplatin in patients with advanced non-small cell lung cancer

S-1 is an oral anticancer fluoropyrimidine agent designed to elevate anticancer activity with a decrease in gastrointestinal toxicity. We conducted a phase II study to evaluate the efficacy and safety of combination chemotherapy with S-1 plus cisplatin in patients with advanced non-small cell lung cancer (NSCLC). Chemotherapy-naïve patients were treated with S-1 administered orally at 40 mg/m(2) twice a day for 21 consecutive days, and cisplatin (60 mg/m(2)) infused intravenously on day 8, repeated every 5 weeks. Of the 44 patients enrolled in the study, 40 were assessable for efficacy and safety. The median number of cycles administered was 3 (range 1-9 cycles). Among the 40 assessable patients, 7 partial responses were observed, with an overall response rate (RR) of 17.5% [95% confidence interval (CI), 5.2-29.8]. Patients with squamous cell carcinoma showed a significantly higher RR (55.5%) than those with adenocarcinoma (9.1%) or other types of NSCLC (0%). The median progression-free survival was 4.3 months (95% CI, 3.4-4.9), the median survival time was 17.9 months (95% CI, 15.0-20.8), and the 1- and 2-year survival rates were 63.3 and 27.3%, respectively. Major grade 3-4 hematologic toxicities were leukocytopenia (7.5%), neutropenia (5.0%), anemia (15.0%) and thrombocytopenia (2.5%). No grade 4 non-hematologic toxicity or treatment-related death occurred. These results suggest that combination chemotherapy with S-1 plus cisplatin is a promising therapeutic candidate for patients with advanced NSCLC, particularly squamous cell carcinoma.

Management of adjuvant S-1 therapy after curative resection of gastric cancer: dose reduction and treatment schedule modification

BACKGROUND

The aim of this study was to determine the optimal management of adjuvant S-1 therapy for stage II or III gastric cancer, encompassing the details of dose reduction and treatment schedule modification.

METHODS

We retrospectively examined 97 patients with stage II or III gastric cancer who received S-1 chemotherapy following gastrectomy between January 2003 and December 2007. S-1 (80 mg/m² per day) was orally administered twice daily for 4 weeks, followed by a 2-week rest. As a rule, treatment was continued for 1 year after gastrectomy. Dose reduction or treatment schedule modification was performed according to toxicity profiles.

RESULTS

Among the 97 patients, 57 (59%) underwent dose reduction at least once and 39 (40%) received treatment schedule modification. Of the 57 patients who required dose reduction, 45 (79%) underwent reduction within 3 months of the beginning of treatment. The most common reasons for dose reduction were anorexia (47%), followed by diarrhea (32%), leukopenia (24%), and rash (16%), with the reasons overlapping. Although the difference in the requirement for dose reduction was not significant, patients with a low creatinine clearance level or those who underwent total gastrectomy had a greater tendency to require dose reduction. The duration of the S-1 treatment period was at least 3 months in 88% of the patients, at least 6 months in 82%, and the planned 1-year period in 73% of the patients.

CONCLUSIONS

In most patients, the planned 1-year adjuvant S-1 therapy for stage II or III gastric cancer could be completed by modifying the dose reduction and treatment schedule.

A multi-institution phase I/II trial of triweekly regimen with S-1 plus cisplatin in patients with advanced non-small cell lung cancer

INTRODUCTION

To determine the dose-limiting toxicity and recommended dose (RD) of cisplatin (CDDP) combined with S-1 (tegafur, 5-chloro-2, 4-dihydroxypyridine, and potassium oxonate) for patients with non-small cell lung cancer and to evaluate efficacy and toxicity of this regimen at RD.

METHODS

Patients with stages III and IV non-small cell lung cancer received 3-week cycles of treatment, each consisting of oral administration of S-1 at 80 mg/m in 2 divided doses per day for 14 consecutive days, intravenous administration of CDDP (60 mg/m, 70 mg/m, or 80 mg/m) on the first day, and no medication during the subsequent 7 days. The primary objective of phase I study was to estimate the maximum tolerable dose and the RD, and the primary end point of phase II study was response.

RESULTS

RD of CDDP in the analysis of 18 eligible patients was 60 mg/m. Evaluation of efficacy and toxicity at RD in 55 eligible patients showed that partial response was observed in 18 patients (32.7%, 95% confidence interval: 20.7-46.7%). The median survival time was 18.1 months, and the time to disease progression was 3.8 months. Grade 3 or severer adverse events were observed in 27 patients (49.1%).

CONCLUSIONS

CDDP combined with S-1 showed a satisfactory overall survival time and acceptable toxicity profile. However, the response as the primary end point did not reach the predetermined threshold level.

Molecularly evolved thymidylate synthase inhibits 5-fluorodeoxyuridine toxicity in human hematopoietic cells

Thymidylate synthase (TS) inhibitors, such as 5-fluorouracil (5-FU) and 5-fluorodeoxyuridine (5-FUdR), are amongst the most frequently used chemotherapeutic drugs available, although their efficacy is often limited by myelotoxicity. An emerging strategy for overcoming bone marrow toxicity involves ex vivo genetic transfer of drug resistance to autologous hematopoietic progenitor cells, followed by reimplantation of the transfected cells before chemotherapy. Here we establish that expression of mutant TS genes, selected from millions of engineered variants, renders human hematopoietic cells resistant to 5-FUdR, and identify the most efficacious variant for gene therapeutic rescue of drug-induced myelosuppression.

Phase I trial of oxaliplatin plus S-1 chemotherapy in patients with metastatic colorectal cancer

Advanced colorectal cancer can be effectively treated with S-1, as well as with a combination of oxaliplatin, 5-fluorouracil (5FU) and leucovorin (LV). However, S-1 together with oxaliplatin may provide a more convenient alternative to 5FU/LV. To evaluate the performance of S-1 combined with oxaliplatin for patients with colorectal cancer, we conducted a Phase I clinical trial in an outpatient setting. We administered S-1 to 15 patients with advanced colorectal adenocarcinoma for two weeks followed by one week of rest. Oxaliplatin was also administered on day 1 of the S-1 cycle. The dose of oxaliplatin was increased from 40 to 85 mg/m(2) to define the maximum tolerated dose and recommended dose in preparation for a Phase II trial. We administered 102 courses of treatment to 15 patients. Grade 3 thrombocytopenia developed in only 1 patient at a dose of 85 mg/m(2) of oxaliplatin plus oral S-1. No other grade 3-4 toxicities developed. No dose-limiting toxicity developed at level 4 of our regimen (oxaliplatin 85 mg/m(2)), and the recommended dose for a Phase II trial was 85 mg/m(2) of oxaliplatin in an outpatient setting.

Standard First-Line Chemotherapy for Metastatic Gastric Cancer in Japan Has Met the Global Standard: Evidence From Recent Phase III Trials

In Japan, standard first-line chemotherapy for metastatic gastric cancer was initially 5-fluorouracil (5-FU) monotherapy. This is based on the Japan Clinical Oncology Group (JCOG) 9205 phase III trial. Based on recent Japanese phase III trials, S1 plus cisplatin combination chemotherapy was established as the standard first-line chemotherapy, and this combination has met the global standard regimen of 5-FU (capecitabine) plus a platinum analog (cisplatin or oxaliplatin). Since the same standard regimen has been established outside Japan, many global trials are currently ongoing in other countries aside from Japan. With the recent development of many molecular targeted agents, global collaboration in clinical trials is necessary for their immediate evaluation. We review the results of recent phase III trials of first-line chemotherapy for metastatic gastric cancer in Japan and other countries.

Phase II trial of S-1 and cisplatin with concurrent radiotherapy for locally advanced non-small-cell lung cancer

BACKGROUND

To assess the efficacy and safety of S-1 and cisplatin with concurrent thoracic radiation for unresectable stage III non-small-cell lung cancer (NSCLC).

METHODS

Eligible patients were 20-74 years old and had histologically or cytologically confirmed NSCLC, a performance status of 0-1, and no prior chemotherapy. Patients were treated with cisplatin (60 mg m(-2) on day 1) and S-1 (orally at 40 mg m(-2) per dose, b.i.d., on days 1-14), with the treatment repeated every 4 weeks for four cycles. Beginning on day 2, a 60-Gy thoracic radiation dose was delivered in 30 fractions.

RESULTS

Of 50 patients, 48 were eligible. Partial response was observed in 42 patients (87.5%; 95% CI: 79.1-96.9%). This regimen was well tolerated. Common toxicities included grade 3/4 neutropenia (32%), grade 3/4 leukopenia (32%), grade 3/4 thrombocytopenia (4%), grade 3 febrile neutropenia (6%), grade 3 oesophagitis (10%), and grade 3 pneumonitis (5%). Median progression-free survival was 12.0 months and median overall survival was 33.1 months. The 1- and 2-year survival rates were 89.5 and 56%, respectively.

CONCLUSION

This chemotherapy regimen with concomitant radiotherapy is a promising treatment for locally advanced NSCLC because of its high response rates, good survival rates, and mild toxicities.