Dropout after Neoadjuvant Chemoimmunotherapy for Non-Small Cell Lung Cancer in the Veterans Health Administration

Multiple studies have demonstrated excellent survival for patients with advanced non-small cell lung cancer who undergo induction chemoimmunotherapy followed by surgery. However, up to 22% of patients in these studies did not undergo surgical resection. National Veterans Health Administration data outlining the uptake, utilization, and dropout in this cohort are limited. We sought to describe utilization, non-progression to surgery, and outcomes in this cohort.

Using the United States Veterans Health Administration database, we identified patients with clinical stage (cStage) IB-III-N2 non-small cell lung cancer who underwent chemoimmunotherapy (2021-2024). All patients received at least 2 cycles CIO. Exclusion criteria included radiation during chemoimmunotherapy, clinical N3 disease, >4 cycles chemoimmunotherapy, or cStage IV disease. Clinicopathological characteristics and treatment patterns were described. Overall survival (OS) was estimated using the Kaplan-Meier method.

In total, 86 patients met final inclusion criteria: 60 (69.8%) underwent surgery and 26 (30.2%) did not. The groups had similar cStage, age, and comorbidities. Among patients who did not undergo surgery, 46.2% developed distant metastatic disease during induction therapy. The 2-year OS was 80.2% for the entire cohort (86.7% surgical; 65.8% non-surgical).

In our nationally representative cohort, patients undergoing chemoimmunotherapy with intent for surgical resection had favorable intermediate-term survival. however, nearly one-third of patients did not undergo surgery, most commonly due to disease progression. These findings highlight the need to better identify patients who do not progress to resection and define management strategies for these patients.