SEER-based analysis of impact of socioeconomic factors in locoregional gastroesophageal junction cancer

Gastroesophageal junction cancer (GEJC) is a rising global health concern with variable outcomes. The availability of high-volume cancer centers may influence survival, yet disparities related to geography and socioeconomic status remain poorly defined. A retrospective cohort study was conducted using the SEER 21 Research Plus database (2000-2022). A total of 40,273 patients with locoregional GEJC were included. Patient-level variables included age, sex, race, histolgy, stage, and survival. Socioeconomic and geographic variables included county-level median household income and rural-urban residence. Residence in states with lower-volume centers was associated with worse outcomes than residence in states with high-volume centers. Each step toward lower-volume categories was associated with an increased hazard of death (HR 0.923; p<0.001). While stage at diagnosis varied significantly across hospital volume categories (p<0.001), no clear pattern of more advanced stage in lower-volume states was observed. Patients with adenocarcinoma had a 25% lower hazard of death compares to those with squamous cell carcinoma (HR 0.752; p<0.001). Female gender was associated with a statistically significant increase in hazard of death compared to males (HR 1.042; p=0.004). Additionally, higher median household income was associated with improved survival (HR 1.006; p<0.001 per category increase), and urban residence (HR 1.036; p<0.001) was independently associated with improved survival. The authors conclude that survival in locoregional GEJC is influenced by both tumor biology and healthcare access.