Are there any molecular predictors for response to chemoimmunotherapy for patients with ES-SCLC?

The short answer is no, there are no validated, clinically useful biomarkers to predict benefit (or lack of benefit) with immune checkpoint inhibitors for patients with SCLC.

Early studies, including KEYNOTE-028 and KEYNOTE-158, suggested that PD-L1 TPS (tumor proportional score) correlated with resp...

The S2409-PRISM is a randomized phase II trial that aims to address the crucial question of predictive biomarkers in SCLC, and will also determine whether the addition of biomarker-guided combination maintenance therapy improves outcomes compared to standard chemoimmunotherapy. Molecular classificat...

No. Molecular testing is something we often do but I would not consider it standard. PD-L1 has not correlated with outcomes for first-line chemo-immunotherapy. Expression of transcriptional regulators is under investigation but has not yet been shown to impact care.

Unless you test you will never find it. Certain tumor agnostic therapies such as for NTRK can be useful to patients. I will test for good performance status at progression and use clinical judgement in the absence of clinical trials.