A population-based study conducted in the Netherlands found no significant differences in survival among patients with synchronous or metachronous metastatic esophageal and gastric adenocarcinoma who received first-line systemic treatment, according to results presented at the ESMO Virtual Congress 2020.

“Real-world data on treatment patterns and outcomes in synchronous versus metachronous metastatic disease in esophagogastric adenocarcinoma are not available,” wrote the researchers. “The aim of our study was to compare patient and tumor characteristics, first-line systemic treatment, overall survival (OS) and time to treatment failure (TTF).”

The researchers used the Netherlands Cancer Registry to identify 3311 patients with synchronous metastases diagnosed between 2015 and 2017 and 792 patients with metachronous metastases who received treatment with curative intent in 2015 and 2016.

Patients with synchronous metastases tended to be older (median age, 69 years vs. 66 years; P < .01) and to have a higher median body-mass index (24.9 vs. 22.9 kg/m²; P < .01).

A greater proportion of patients with synchronous metastases received systemic treatment as first-line treatment (43% vs. 33%; P < .01).

The researchers observed that patients with synchronous metastases had worse survival outcomes than patients with metachronous metastases; however, the difference did not reach statistical significance (median OS, 4.2 vs. 3.4 months; adjusted hazard ratio [HR], 1.12; 95% CI, 1.02-1.22).

In terms of chemotherapy, patients with synchronous metastases more frequently received EOX/ECC regimens (15% vs. 6%), whereas patients with metachronous metastases more frequently received CapOx/FOLFOX regimens (54% vs. 47%).

Among those who received first-line systemic treatment, there were no significant differences observed between patients with synchronous metastases and metachronous metastases with regard to TTF (median, 5.3 months vs. 5 months; adjusted HR, 1.05; 95% CI, 0.89-1.23) or OS (7.6 months vs. 7.1 months; adjusted HR, 0.98; 95% CI, 0.84-1.15).