Effectiveness and safety of serplulimab plus platinum-based chemotherapy in first-line treatment of extensive-stage small cell lung cancer liver metastases: a retrospective cohort study

Background The role of immunotherapy in patients with extensive-stage small cell lung cancer (ES-SCLC) liver metastases remains controversial. This study aimed to evaluate the effectiveness and safety of serplulimab combined with platinum-based chemotherapy as a first-line treatment for these patients. Methods This retrospective cohort study reviewed patients with ES-SCLC liver metastases who received serplulimab plus platinum-based chemotherapy as a first-line treatment. Outcomes included objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS), overall survival (OS), and safety. The associations between prognosis and the depth of remission of primary lung lesions and liver metastases were analyzed. Results Among the 30 ES-SCLC patients (median age, 67 years), the ORR was 63.3% (95% CI, 43.9-80.1), and the DCR was 83.3% (95% CI, 65.3-94.4). The median PFS was 5.9 months (95% CI, 4.3-8.1), and the median OS was 9.1 months (95% CI, 6.1-16.2). Patients with a depth of remission of primary lung lesions ≥30% (n=14) had a significantly longer median PFS (8.1 months [95% CI, 6.4-NE] vs. 3.9 months [95% CI, 3.2-6.3], HR:0.28, 95%CI: 0.12-0.65) and OS (16.2 months [95% CI, 9.1-NE] vs. 5.5 months [95% CI, 3.7-13.6], HR: 0.31, 95%CI: 0.12-0.81) than those with a depth of remission <30% (n=16). Patients with a depth of remission of liver metastases ≥30% (n=9) had a significantly extended median OS than those with a depth of remission <30% (n=20) (16.2 months [95% CI, 10.4-NE] vs. 6.3 months [95% CI, 4.4-13.6], HR: 0.21, 95%CI: 0.06-0.73). The most common adverse events were nausea (40.0%), leukopenia (26.7%), and neutropenia (26.7%). Conclusion This real-world study demonstrates promising effectiveness and a manageable safety profile for the combination of serplulimab with platinum-based chemotherapy in treating ES-SCLC liver metastases, which suggests that this treatment regimen may provide an attractive option for the first-line management of ES-SCLC liver metastases.