Anti-PD-L1 immune checkpoint inhibitors in combination with etoposide and platinum for extensive-stage small cell lung cancer: a case report

The conventional etoposide-platinum (EP) regimen and adjuvant radiotherapy remain the gold-standard treatment for small cell lung cancer (SCLC). However, most patients already have multiple metastases when they are first diagnosed with SCLC. The objective response rate (ORR) and 1-year survival rate are low in these patients despite active radiotherapy and chemotherapy. SCLC is oncologically featured by the high tumor mutational burden (TMB) of multiple genes, which makes immunotherapy a possible new treatment strategy for SCLC. New data from the IMpower 133 and CASPIAN trials will shed new light on the treatment of SCLC. In 2020, the results from the phase 3 CASPIAN trial have already suggested that programmed cell death-ligand 1 (PD-L1) inhibitors may represent breakthroughs in the management of SCLC. Here, we report a patient with extensive-stage SCLC (ES-SCLC) treated with first-line anti- PD-L1 immune checkpoint inhibitor (PD-L1 inhibitor) (i.e., durvalumab) combined with the EP regimen for 6 cycles. The patient consistently achieved partial response (PR) [nearly complete response (CR)], and no immune-related adverse events were noted during this period. The Karnofsky performance status (PS) score maintained at 1-2 points. We further review the history of SCLC treatment and elucidate the role of combination with immunotherapy in treating SCLC in the coming years.