Real-world surgical and treatment patterns after neoadjuvant checkpoint inhibition in US patients with stage II/III non-small cell lung cancer.

8078 Background: Since 2021, several immuno-oncology (IO) agents were approved for use in patients with resectable non-small cell lung cancer. In the phase III neoadjuvant and perioperative IO trials, 16-26% of patients did not undergo surgery. The objectives of this study were to evaluate the real-world rate of surgery following neoadjuvant IO, reasons for preoperative attrition to resection, and subsequent treatment patterns for those who did not undergo surgery. Methods: This retrospective observational study used the nationwide Flatiron Health electronic health record-derived deidentified database. Included were patients diagnosed with stage II or III NSCLC between Jan 2022 and Oct 2023 who received nivolumab (nivo) and doublet chemotherapy (CT) as the first therapy within 90 days of diagnosis. We excluded patients with no documented neoadjuvant intent from the no surgery group. Per approved protocol, descriptive statistics were utilized for patient characteristics and treatment patterns. Results: A total of 484 patients received nivo. Among these, the average age was 67 years, 253/484 (52.3%) were male, 339/484 (70.0%) were white, and 403/484 (83.3%) were treated in a community setting. The rate of surgery was 317/484 (65.5%). Rates by stage and ECOG are found in Table 1. Among those most similar to the population in clinical trials (ECOG 0-1 and Stage IIA-IIIA) the rate was 238/334 (71.3%). The most common reasons for attrition were medical fitness (45/484; 9.2%), tumor resectability (30/484; 6.2%), and progression (28/484; 5.8%). Of those not receiving surgery, 131/167 (78.4%) received subsequent treatment, including 57 who received radiation (+/- chemo) during the follow-up period (median 10.5 months from diagnosis). Conclusions: In this real-world analysis, most patients were treated in community centers. The resection rate following neoadjuvant CT-IO in stage II and III NSCLC was high and comparable to the clinical trials. Medical operability, tumor resectability, and progression of disease as reasons for preoperative attrition to surgery occurred in a minority of patients that received neoadjuvant therapy. Many of the patients who did not undergo resection received subsequent therapy including consolidation radiation. Future research is needed to determine ways to improve surgical rates following neoadjuvant CT-IO. Surgical rates by ECOG and stage at diagnosis. Stage IIA Stage IIB Stage II (unspecified) Stage IIIA Stage IIIB Stage IIIC Stage III (unspecified) ECOG 0-1 28/35 (80.0%) 80/97 (82.5%) 7/10 (70.0%) 123/192 (64.1%) 11/24 (45.8%) 0/7 (0%) 5/5 (100.0%) ECOG ≥2 1/4 (25.0%) 4/10 (40.0%) 0/0 (0%) 4/13 (30.8%) 1/5 (20.0%) 0/1 (0%) 0/0 (0%) Unknown 5/6 (83.3%) 16/26 (61.5%) 1/1 (100.0%) 27/41 (65.9%) 2/4 (50.0%) 0/0 (0%) 2/3 (66.7%) Overall 34/45 (75.6%) 100/133 (75.2%) 8/11 (72.7%) 154/246 (62.6%) 14/33 (42.4%) 0/8 (0%) 7/8 (87.5%)