Combination of low-dose docetaxel and standard-dose S-1 for the treatment of advanced gastric cancer: efficacy, toxicity, and potential predictive factor

The Impact of the Expression Level of Intratumoral Dihydropyrimidine Dehydrogenase on Chemotherapy Sensitivity and Survival of Patients in Gastric Cancer: A Meta-Analysis

The potential impact that the intratumoral expression level of dihydropyrimidine dehydrogenase (DPD) has on chemotherapy sensitivity and long-term survival for gastric cancer (GC) patients remains controversial; therefore, this study seeks to clarify this issue. Our meta-analysis was performed using Review Manager (RevMan) 5.3 software. In vitro drug sensitivity tests, correlation coefficients between sensitivity to 5-fluorouracil (5-FU), and expression levels of intratumoral DPD were used as effective indexes to analyse. Overall survival (OS) and progression-free survival (PFS) were used as endpoints for patient outcome, and hazard ratios (HRs) and 95% confidence intervals (CIs) were noted as measures of effect. There were 15 eligible studies including 1805 patients for the final analysis. The analysis revealed a statistically significant difference between the expression level of intratumoral DPD activity, DPD mRNA levels, and sensitivity to 5-FU in GC patients, with high expression levels of intratumoral DPD resulting in low sensitivity to 5-FU. However, no matter what therapeutic regimens were used, there was no significant difference for patient outcomes between high and low DPD expression groups, either in OS or in PFS. In conclusion, high levels of intratumoral DPD expression have a negative impact on sensitivity to 5-FU in GC patients, but no prognostic value for long-term survival was uncovered.

Phase II trial of S-1 plus leucovorin in patients with advanced gastric cancer and clinical prediction by S-1 pharmacogenetic pathway

Background

The first one-arm phase II trial aimed to evaluate and predict efficacy and safety of S-1 plus oral leucovorin (S-1/LV) as first-line chemotherapy for patients with advanced gastric cancer (AGC), using S-1 pharmacogenetic pathway approach.

Patients and methods

A total of 39 patients orally took S-1 at conventional dose and LV simultaneously at a dose of 25 mg twice daily for a week, within a 2-week cycle. The primary endpoint was overall response rate (ORR), while the secondary endpoints were progression-free survival (PFS), time to failure (TTF), overall survival (OS), disease control rate (DCR), and adverse events (AEs). Peripheral blood was sampled prospectively for baseline expression of dihydropyrimidine dehydrogenase (DPD), orotate phosphoribosyltransferase (OPRT), thymidine phosphorylase (TP), and thymidylate synthase (TS), CYP2A6 gene polymorphisms, and 5-FU pharmacokinetics.

Results

The ORR and DCR were 41.0 and 76.9%. The median PFS, TTF, and OS were 4.13, 3.70, and 11.40 months. Grade 3–4 AEs occurred in only 13 patients, and grade 4 AEs occurred in only 1 of them. High OPRT/TS and peritoneal metastasis (vs. liver metastasis) independently predicted responding. High OPRT/DPD independently predicted grade 3–4 AEs. High AUC_0–24h of 5-FU and metastatic/recurrent sites ≤2 (vs. >3) independently predicted prolonged PFS. Low baseline plasmic DPD independently predicted prolonged OS.

Conclusions

Two-week, oral S-1/LV regimen demonstrated promising efficacy and safety as first-line chemotherapy for AGC.

ClinicalTrials.gov identifier

NCT02090153

Electronic supplementary material

The online version of this article (doi:10.1007/s00280-016-3209-1) contains supplementary material, which is available to authorized users.

Low-dosed docetaxel showed equivalent efficacy but improved tolerability compared with oxaliplatin in the S-1-based first-line chemotherapy regimen for metastatic or recurrent gastric adenocarcinoma

Platinum-fluoropyrimidine combinations are the preferred first-line options for advanced gastric cancer (AGC) in East Asia. On the other hand, docetaxel-containing regimens without platinum have demonstrated promising activity in AGC. However, dose-related toxicity of docetaxel has limited its clinical adoption. This study compared the efficacy and safety of a modified low-dosed docetaxel plus S-1 (mDS) with oxaliplatin plus S-1 (SOX) in Chinese patients with AGC. Patients were assigned to receive either oxaliplatin (100 mg/m(2)) in the SOX arm or docetaxel (40 mg/m(2)) in the mDS arm on day 1 of every 3-week cycle. S-1 80-120 mg/day was administered orally on days 1-14 in the 3-week cycle in both groups. One hundred and eighty-eight patients (mDS regimen 101; SOX 87) showed similar overall survival (OS; 13.1 vs 12.8 months, P = 0.878), progression-free survival (PFS; 5.8 vs 5.5 months, P = 0.924), and overall response rate (39.7 vs 44.2%, P = 0.569) in the mDS and SOX arms, respectively. mDS was associated with significantly less grade 3/4 toxicities in thrombocytopenia (5.9 vs 16.1%) and gastrointestinal disturbances (1.0 vs 8.0%). Furthermore, in patients who had ever received oxaliplatin-based adjuvant chemotherapy (N = 40), mDS resulted in significantly superior OS (17.8 vs 9.5 months, P = 0.015) and PFS (7.0 vs 4.2 months, P = 0.008) compared with SOX. In conclusion, mDS was as effective as SOX in Chinese patients with AGC, but it resulted in a significantly improved tolerability. In patients who received oxaliplatin-based adjuvant chemotherapy before, mDS was associated with improved efficacy in the first-line setting.

Impact of intratumoral expression levels of fluoropyrimidine-metabolizing enzymes on treatment outcomes of adjuvant S-1 therapy in gastric cancer

We analyzed the expression levels of fluoropyrimidine-metabolizing enzymes (thymidylate synthase [TS], dihydropyrimidine dehydrogenase [DPD], thymidine phosphorylase [TP] and orotate phosphoribosyltransferase [OPRT]) to identify potential biomarkers related to treatment outcomes in gastric cancer (GC) patients receiving adjuvant S-1 chemotherapy. In this study, 184 patients who received curative gastrectomy (D2 lymph node dissection) and adjuvant S-1 were included. Immunohistochemistry and quantitative reverse transcription polymerase chain reaction were performed to measure the protein and mRNA levels of TS, DPD, TP, and OPRT in tumor tissue. In univariate analysis, low intratumoral DPD protein expression was related to poorer 5-year disease-free survival (DFS; 78% vs. 88%; P = 0.068). Low intratumoral DPD mRNA expression (1st [lowest] quartile) was also related to poorer DFS (69% vs. 90%; P < 0.001) compared to high intratumoral DPD expression (2nd to 4th quartiles). In multivariate analyses, low intratumoral DPD protein or mRNA expression was related to worse DFS (P < 0.05), irrespective of other clinical variables. TS, TP, and OPRT expression levels were not related to treatment outcomes. Severe non-hematologic toxicities (grade ≥ 3) had a trend towards more frequent development in patients with low intratumoral DPD mRNA expression (29% vs. 16%; P = 0.068). In conclusion, GC patients with high intratumoral DPD expression did not have inferior outcome following adjuvant S-1 therapy compared with those with low DPD expression. Instead, low intratumoral DPD expression was related to poor DFS.

Nanoparticle Delivery Systems Reduce the Reproductive Toxicity of Docetaxel in Rodents

Various docetaxel (DTX)-loaded nanoparticle delivery systems have been designed to enhance the solubility and pharmacological effects of DTX. However, the toxicity changes of these nano-modified DTX (nano-DTX) are not yet clear enough. Herein, to compare the reproductive toxicity between conventional DTX and nano-DTX, we performed sperm toxicity test in mice, and fertility and early embryo-fetal developmental toxicity test in rats. It was found that DTX severely repressed spermatogenesis and sperm motility, and dramatically increased sperm abnormality in mice and rats. Moreover, DTX significantly decreased copulation, conception and fertility indexes in rats, and no positive pregnant female rat was obtained after treatment with DTX. However, nano-DTX significantly reduced DTX-induced toxicity to sperm. Most importantly, nano-DTX obviously converted DTX-induced fertility and early embryo-fetal developmental toxicity. Furthermore, organ weights and histopathology examination revealed DTX, but not nano-DTX, significantly decreased testis and epididymis weights, and induced obvious histopathological atrophy of testes and epididymides in rats. Further studies indicated that changed activity of lactate dehydrogenase C4 (LDH-C4) in rodents testes was mainly responsible for the above observations. These results strongly support the idea that DTX-loaded nanoformulations have the potential to overcome the reproductive toxicity of DTX.

Docetexal plus S-1 versus oxaliplatin plus S-1 for first-line treatment of patients with advanced gastric cancer: a retrospective study

BACKGROUND

Both docetexal plus S-1 (DS) and oxaliplatin plus S-1 (SOX) are active regimens currently used in patients with advanced gastric cancer. In this retrospective study, efficacy and safety of these 2 combination regimens were evaluated.

PATIENTS AND METHODS

Patients received docetaxel infusion 75 mg/m(2) in the DS group or oxaliplatin infusion 130 mg/m(2) in the SOX group at day 1 of each 3-week cycle. S-1 40 mg/m(2) was administered orally twice daily on days 1-14 in the 3-week cycle in both groups. Progression-free survival (PFS), overall survival (OS) and safety perimeters were evaluated.

RESULTS

84 patients were retrospectively evaluated in the study: 36 patients in the DS group and 48 patients in the SOX group. The median PFS was 6.55 months in the DS group and 5.73months in the SOX group. The median OS was 13.97 in the DS group and 13.13 months in the SOX group. The overall response rates were 41.7% and 43.8% and the disease control rates were 77.8% and 87.5% for DS and SOX, respectively. The most frequent grade 3 and 4 toxicities were thrombocytopenia for DS (19.4%) and anemia for SOX (12.5%).

CONCLUSION

Both regimens were active and well tolerated in advanced gastric cancer patients. © 2014 S. Karger GmbH, Freiburg.

S-1 plus oxaliplatin vs. S-1 as first-line treatment in patients with previously untreated advanced gastric cancer: a randomized phase II study

This randomized phase II study was performed to compare the efficacy and safety of oxaliplatin combined with S-1 (OXS regimen) with S-1 alone in the management of advanced gastric cancer (AGC). Ninety-four patients were 1:1 randomly assigned to S-1 on days 1-14 of a 3-week cycle or S-1 on days 1-14 plus oxaliplatin (130 mg/m(2) i.v.) on day 1 of the 3-week cycle. S-1 was orally administered in a fixed quantity according to body surface area. The median survival time with OXS versus S-1 monotherapy was 14·0 versus 11·0 months (P = 0·03), progression-free survival was 6·5 versus 4·0 months (P = 0·02), and the 1-year survival rate was 63·8% versus 48·9%, respectively. The response rate was significantly higher for OXS than for S-1 monotherapy (51·1% vs. 27·7%, P = 0·03). OXS was well tolerated with no treatment-related death. In conclusion, the OXS regimen evidenced a relatively high efficacy and was well tolerated as a first-line therapy for AGC patients.