232P - How socioeconomic status (SES) shapes lung adenocarcinoma diagnosis and survival in Brazil: A population-based analysis

Background

Lower SES negatively affects cancer outcomes, but comprehensive analyses in Brazil are scarce. This study evaluates the impact of SES on stage at diagnosis and survival in lung adenocarcinoma.

Methods

A cohort of 17,771 pathology-confirmed lung adenocarcinoma cases in patients aged ≥18 years (2000–20) from Fundaça?o Oncocentro de Sa?o Paulo’s database was analyzed. Patient, treatment, and disease characteristics were summarized as medians with interquartile ranges (IQR). Trends in demographics, treatment, and diagnosis-to-treatment intervals were assessed. Survival was estimated by KM analysis.

Results

Median age at diagnosis was 63 years (IQR 20–96), with females comprising 45% of cases. Most diagnoses occurred at advanced stages (III/IV), with stage IV accounting for 62%, followed by stages III (20%), I (12%), and II (5%). Median diagnosis-to-treatment time was 35 days (IQR 11–69), with 30% of patients waiting >60 days for treatment initiation. Stage at diagnosis strongly correlated with survival (p < 0.0001): stage I, 2.8 years (IQR 1.1–5.8); stage II, 2.0 years (IQR 0.7–4.2); stage III, 1.03 years (IQR 0.4–2.2); and stage IV, 0.55 years (IQR 0.2–1.3). Higher GDP and education were linked to earlier diagnoses and improved 5-year survival (p < 0.001). University-educated patients experienced faster treatment initiation and better survival (p < 0.01). Stage I diagnoses were more common among university-educated patients than those with no schooling (20.6% vs. 9.3%, p < 0.001). Female representation and immunotherapy use rose over time (p < 0.001), while treatment delays grew from 20 days (IQR 3–40) in 2000 to 54 days (IQR 24–92) in 2015 (p=0.02). Incident cases rose by ∼29% every four years. Finally, median survival improved over time.

Gender, treatment and survival temporal trends for lung adenocarcinoma