Non-Small-Cell Lung Cancer Patients with Coexistence of High PD-L1 Expression and RET Fusion-Which Path Should We Follow? Case Reports and Literature Review

J Clin Med. 2022 Mar 15;11(6):1630. doi: 10.3390/jcm11061630.


Pembrolizumab is widely used in first-line treatment in patients with advanced non-small-cell lung cancer (NSCLC) with high PD-L1 expression. The activity of pembrolizumab in NSCLC patients with rare molecular alterations is poorly characterised. RET gene rearrangements are identified in 1-2% of lung cancer patients. Here, we present two cases of RET-rearranged NSCLC patients with high PD-L1 expression (>50%), treated with pembrolizumab within routine clinical practice. Pembrolizumab was ineffective in both cases-single-agent immunotherapy seems to be of limited value in this group of patients. Selective RET-inhibitors, if available, are the optimal treatment for patients with RET fusion nowadays. The best sequence of the therapy is still not defined.

Keywords: RET-fusion; case report; immunotherapy; non-small-cell lung cancer; rare molecular alterations.

Publication types

  • Review