IMpower, CASPIAN, and more: exploring the optimal first-line immunotherapy for extensive-stage small cell lung cancer

The life expectancy of extensive-stage small cell lung (ES-SCLC) cancer patients has not improved in the last 2–3 decades until two recent trials (CASPIAN and IMpower133) showing the addition of anti-programmed death ligand (PD-L1) therapy to chemotherapy has survival benefit over chemotherapy alone. However, such benefit is relatively small and was not even observed in some other trials using immunotherapy, raising the question of optimal chemoimmunotherapy combination in the 1st-line setting for ES-SCLC. Here, we discussed several thought-provoking questions with the focus on IMpower133 and CASPIAN trials.