A dose-escalation study of docetaxel, oxaliplatin, and S-1 (DOS) as a first-line therapy for patients with unresectable metastatic gastric cancer

Does resection after neoadjuvant chemotherapy of docetaxel, oxaliplatin, and S-1 (DOS regimen) benefit for gastric cancer patients with single non-curable factor? a multicenter, prospective cohort study (Neo-REGATTA)

BACKGROUND

The Neo-REGATTA study evaluated the effectiveness and safety of Docetaxel, oxaliplatin, and S-1 (DOS regimen) followed by radical resection vs. chemotherapy in advanced gastric adenocarcinoma patients with single non-curable factor.

METHODS

This cohort study prospectively enrolled advanced gastric adenocarcinoma patients with single non-curable factor between November 2017 and June 2021. Patients without progression after four cycles of DOS were divided into resection group and chemotherapy group. The outcomes included overall survival (OS), progression-free survival (PFS) and safety. Effectiveness analysis was also performed by propensity score matching (PSM).

RESULTS

A total of 73 patients were enrolled and 13 patients were withdrawn due to disease progression after 4 cycles of DOS. Afterwards, 35 and 25 participants were in the resection and chemotherapy groups, respectively. After a median follow-up time of 30.0 months, the median PFS and OS were 9.0 months, and 18.0 months for the chemotherapy group, but not reached in the resection group. After PSM, 19 matched participants were in each group, and the median PFS and OS were longer in resection group than that in chemotherapy group. The most common grade 3 or 4 adverse events both in the resection group and chemotherapy groups were neutropenia (5.7%, 8.0%) and leukopenia (5.7%, 8.0%).

CONCLUSIONS

Radical resection might provide survival benefit compared with continuous chemotherapy alone in advanced gastric adenocarcinoma patients who had a disease control after DOS, with a good safety profile.

TRIAL REGISTRATION

The study protocol was registered on ClinicalTrial.gov (NCT03001726, 23/12/2016).

SOX combined with intraperitoneal perfusion of docetaxel compared with DOS regimen in the first-line therapy for advanced gastric cancer with malignant ascites: a prospective observation

Objective

This study aimed to verify the survival superiority of the combination of intraperitoneal perfusion and systemic chemotherapy over standard systemic chemotherapy.

Methods

A total of 78 advanced gastric cancer patients with malignant ascites were randomly divided into D-SOX group (intraperitoneal infusion of docetaxel 30 mg/m² on d1 and d8, intravenous oxaliplatin 100 mg/m² on d1, and oral administration of S-1 on d1-d14) and DOS group (intravenous docetaxel 60 mg/m² on d1, intravenous oxaliplatin 100 mg/m² on d1, and oral administration of S-1 on d1-d14). Efficacy of both groups was evaluated every 2 cycles with 21 days as a cycle. The primary endpoint was overall survival, and the secondary endpoints were objective response rate, ascites control rate, negative conversion rate of ascites cytology, and side effects.

Results

The median overall survival in D-SOX group was significantly higher than that in the DOS group (11.7 vs 10.3 months, HR 0.52, 95%CI 0.31–0.86, P = 0.005). The ascites control rate in the D-SOX group was 58.9% and 30.8% in DOS group (95%CI 42.8–75.1% vs 95%CI 15.6–45.9%, P = 0.012). Besides, the adverse reactions were tolerable in both groups, and patients in the D-SOX group had lower grade 3/4 blood toxicity than that in the DOS group (26% vs 54%, P = 0.01).

Conclusion

Compared with traditional systemic chemotherapy, docetaxel intraperitoneal infusion combined with chemotherapy has better therapeutic effect on gastric cancer ascites, with better survival benefit and tolerance and less hematological toxicity, which is worthy of further research and clinical application.

Survival benefit of conversion surgery after intensive chemotherapy for unresectable metastatic gastric cancer: a propensity score-matching analysis

PURPOSE

The clinical benefit of conversion surgery (CS) for unresectable gastric cancer (GC), whereby unresectable GC responds to chemotherapy and subsequently receives curative-intent surgery, remains unclear. Here, we aimed to clarify the clinical value of CS.

METHODS

In this retrospective cohort study, we analyzed 175 unresectable GC, who received triple combined chemotherapy between 2004 and 2019. We divided patients into two groups: those who underwent CS and those receiving chemotherapy only (CS and C groups, respectively). Propensity score matching was used to minimize confounding bias.

RESULTS

Of 175 cases, 61 (34.9%) underwent CS. R0 resection was obtained in 85.2%. After matching, 44 pairs were selected; there were no significant differences in baseline covariants. Group CS had a significantly better median overall survival (OS) (18.8 vs. 46.0 months, p < 0.001), and prolonged progression-free survival (7.4 vs. 25.8 months, p < 0.001). Subgroup analysis of OS showed a favorable trend for CS for almost all subgroups. Multivariate analysis revealed that good ECOG performance status and CS were associated with a longer OS.

CONCLUSION

The survival benefit of CS was consistently demonstrated in the univariate and multivariate analysis, even in the matched cohort. Additional large-scale trials are needed for further validation.