The following is a summary of “A Novel Radiogenomics Biomarker for Predicting Treatment Response and Pneumotoxicity From Programmed Cell Death Protein or Ligand-1 Inhibition Immunotherapy in NSCLC,” published in the June 2023 issue of the Thoracic Oncology by Chen et al.
The selection of patients for immunotherapy with checkpoint inhibitors is based on the expression of programmed death-ligand 1 (PD-L1) in immunohistochemically stained tumor tissue samples. This method has limitations due to the dynamic and heterogeneous character of cancer cells and the invasiveness of the tissue sampling technique. To address these obstacles, the researchers developed a novel computed tomography (CT) radiomic signature for predicting disease response in patients with NSCLC undergoing immunotherapy with PD-1 or PD-L1 checkpoint inhibitors.
This retrospective study includes 194 patients with suitable CT scans 340. Using the radio mic features computed from segmented tumors on a discovery set of 85 contrast-enhanced chest CTs of patients diagnosed with NSCLC and their CD274 count, RNA expression of the protein-encoding gene for PD-L1, as the response vector, they developed a lung cancer immunotherapy—radionics prediction vector (LCI-RPV). This was confirmed in two independent testing cohorts of 66 and 43 NSCLC patients treated with PD-1 or PD-L1 inhibition immunotherapy, respectively. In both NSCLC testing cohorts, LCI-RPV predicted PD-L1 positivity (area under the curve [AUC] = 0.70, 95% CI: 0.57–0.84 and AUC = 0.70, 95% CI: 0.46–0.94).
In one cohort, it also demonstrated good prediction of cases with high PD-L1 expression exceeding critical treatment thresholds (>50%: AUC = 0.72, 95% CI: 0.59–0.85, and >90%: AUC = 0.66, 95% CI: 0.45–0.88), the tumor’s objective response to treatment at three months (AUC = 0.68, 95% CI: 0.52–0.85), and pneumonitis occurrence (AUC = 0.64, 95% CI: 0.48–0.80). LCI-RPV successfully stratified patients into high- and low-risk survival groups (hazard ratio = 2.26, 95% CI: 1.21–4.24, P = 0.011 and hazard ratio = 2.45, 95% CI: 1.07–5.65, P = 0.035, respectively). A CT radionics-based signature derived from response vector CD274 can aid in determining the suitability of NSCLC patients for immunotherapy with PD-1 or PD-L1 checkpoint inhibitors.