Thyroid dysfunction as a predictor of PD- 1/PD-L1 inhibitor efficacy in advanced lung cancer

To investigate the correlation between thyroid dysfunction (TD) and the efficacy of programmed cell death protein 1 (PD-1) and programmed death ligand 1 (PD-L1) inhibitors in the treatment of advanced lung cancer, and the possible influencing factors for TD occurrence, providing insights that could guide individualized therapeutic approaches.

The data of 120 advanced lung cancer patients from January 2019 to August 2024 were retrospectively collected. Then, the patients were divided into TD and non-TD subgroups according to whether TD occurred or not, to analyse the possible factors influencing the occurrence of TD and the correlation between TD and PD-1/PD-L1 inhibitor efficacy.

For all cases, the baseline TSH level was significantly higher in the TD subgroup than in the non-TD subgroup (median: 2.33 mIU/L vs. 1.58 mIU/L, p = 0.001). The progression-free survival (PFS) was significantly longer in the TD subgroup than in the non-TD subgroup (mPFS: 7.90 months vs. 4.87 months, p = 0.003), and the patients in the TD subgroup had a lower HR for progression (0.499, 95% CI (0.317-0.766)). For the PD-1/PD-L1 inhibitor group, the baseline TSH level was also significantly higher in the TD subgroup than in the non-TD subgroup (median: 2.16 mIU/L vs. 1.52 mIU/L, p = 0.009). The PFS was also significantly longer in the TD subgroup than in the non-TD subgroup (mPFS: 8.83 months vs. 6.50 months, p = 0.041).

The baseline TSH level was the predictive factor for the occurrence of TD. The occurrence of TD was positively associated with a favorable prognosis for patients with advanced lung cancer.