Results
Analyses included 3077 patients with stage I (n = 1673), II (n = 853), and III (n = 551) disease. Most (92.8%, 52.3%, and 36.5% of stage I, II, and III patients) received surgery without systemic therapy. Among stage I, II, and III patients, 7.2%, 44.8%, and 46.6% received adjuvant therapy only. Of stage II and III patients, 2.0% and 10.2% received neoadjuvant therapy only, and 0.9% and 6.7% received both (stage I patients who received neoadjuvant only or perioperative therapy were excluded because of low numbers [n = 4]). Five-year overall survival rates were 73.4%, 61.9%, and 50.5% in stage I, II, and III patients; 5-year real-world relapse-free survival rates were 35.4%, 23.1%, and 14.0%. In an exploratory multivariate analysis, neoadjuvant treatment was associated with improved overall survival and real-world relapse-free survival in stage II–III patients (stage I patients not evaluable). Adjuvant treatment was associated with improved real-world relapse-free survival, but not overall survival, in stage II–III patients.
Conclusions
Most patients received surgery alone, though the proportion receiving systemic treatment increased with disease stage. Modest 5-year, real-world relapse-free survival rates indicate a need for more effective neoadjuvant or adjuvant treatments in this setting.