Serplulimab monotherapy in extensive-stage small-cell lung cancer with brain metastasis: a case report

Small-cell lung cancer (SCLC) is an aggressive form of lung cancer with limited treatment options, especially for extensive-stage (ES) patients. We present a case of a 70-year-old male with ES-SCLC and asymptomatic brain metastasis who opted for immune monotherapy with serplulimab (an anti-PD-1 antibody). After four cycles, the patient achieved a confirmed partial response and a progression-free survival of over 1 year. Moreover, we observed a consistent decline in tumor biomarkers, and brain MRI indicated reduced metastatic activity. Remarkably, the patient tolerated the treatment well, with only mild diarrhea. This case highlights serplulimab's potential as a first-line treatment in select ES-SCLC patients, emphasizing the importance of further research on immunotherapy predictive biomarkers.