ESMO Asia Virtual Congress 2020

Abstract 131P

Background

The factors associated with a better tumor response rate and an optimal neoadjuvant chemotherapy regimen are uncertain. We aimed to validate the prognostic value of tumor regression grading (TRG) and explore the associated factors of TRG for advanced gastric cancer (AGC) with neoadjuvant chemotherapy (NACT) plus surgery.

Methods

Three hundred forty-four AGC patients treated with NACT followed by gastrectomy at the Mayo Clinic, USA and the Fujian Medical University Union Hospital, China between January 2000 and December 2016 were enrolled in this study. Cox regression was used to identify covariates associated with overall survival (OS) and recurrence-free survival (RFS). Logistic regression was used to reveal factors predicting the tumor regression grading.

Results

For patients with TRG 0-1, the 3- and 5-year OS rates were 85.2% and 74.5%, respectively, when compared to 56.1% and 44.1% in patients with TRG 2 and 28.2% and 23.0% in patients with TRG 3, respectively(p=0.000). TRGs were independent risk factors for OS. Similar findings were observed in RFS. The oxaliplatin-based regimen was superior to the non-oxaliplatin-based regimen for the OS (38.4m vs 19.5m, respectively; p=0.01). Subgroup analyses by histological subtype indicated that the oxaliplatin-based regimen improved the OS in non-signet ring cell carcinoma compared to the non-oxaliplatin-based regimen (53.7m vs 19.5m, respectively; p=0.011). However, Similar findings were not observed in RFS.

Conclusions

TRG was an independent factor of AGC treated with neoadjuvant chemotherapy plus surgery. Oxaliplatin-based neoadjuvant chemotherapy regimens improve tumor response and may have an overall survival benefit for patients with non-signet ring cell carcinoma.