Does HER2 status influence in the benefit of ramucirumab and paclitaxel as second line treatment of advanced gastro-esophageal adenocarcinoma? Data from the AGAMENON-SEOM registry.

PURPOSE: This study aimed to compare ramucirumab-paclitaxel versus chemotherapy in second-line (2L) advanced gastroesophageal cancer (aGEC) based on HER2 status and analyze prognostic factors.
METHODS: The study includes patients from the AGAMENON-SEOM registry with aGEC and known HER2 status who received 2L between 2016 and 2021. The Kaplan-Meier method was used to calculate progression-free survival (PFS) and overall survival (OS) and multivariable Cox regression analysis was done to adjust for confounding variables.
RESULTS: Of the 552 patients who met the selection criteria, 149 (26.9%) had HER2-positive aGEC, 89 were treated with chemotherapy, and 60 with ramucirumab-paclitaxel, and 403 had an HER2-negative aGEC, 259 were treated with chemotherapy, and 144 with ramucirumab-paclitaxel. In the whole sample, 2L PFS was 3.0 months (95% CI 2.8-3.2), 2L OS, 5.7 months (5.2-6.3), and ramucirumab-paclitaxel versus chemotherapy was associated with increased PFS (HR 0.64, 95% CI 0.53-0.78, p < 0.0001) and OS (HR 0.68, 0.55-0.83, p = 0.0002). Median PFS of ramucirumab- paclitaxel versus chemotherapy was 3.5 vs 2.8 months (HR 0.67, 0.54-0.83, p = 0.0004) in HER2-negative, and 4.7 vs 2.7 months (HR 0.57, 0.40-0.82, p = 0.0031) in HER2-positive aGEC, respectively. Median OS for ramucirumab-paclitaxel versus chemotherapy was 6.6 vs 5 months (HR 0.67, 0.53-0.85, p = 0.0007) in HER2-negative, and 7.4 vs 5.6 months (HR 0.70, 0.53-1.04, p = 0.083) in HER2-positive aGEC, respectively. ECOG-PS, tumor burden, Lauren subtype, and neutrophil-lymphocyte ratio were prognostic factors.
CONCLUSIONS: In patients with an aGEC from the AGAMENON-SEOM registry, 2L treatment with ramucirumab-paclitaxel was superior to chemotherapy in PFS, OS and response rate, independent of HER2 status.