A retrospective analysis of prognostic factors and treatment choices in small cell lung cancer with liver metastasis.

Background: Small cell lung cancer (SCLC) is characterized by high aggressiveness and early dissemination, with the liver being the most common site of metastasis. Although it has been established that the prognosis for SCLC with liver metastasis is exceedingly poor, comprehensive data on clinical features, prognostic factors, treatment options, and outcomes of this patient population remain limited. This retrospective study aims to examine the clinicopathological features and current treatment landscape and to identify prognostic factors associated with SCLC with liver metastasis in real-world settings. Methods: We conducted a retrospective analysis of data on SCLC patients with liver metastasis at initial diagnosis between January 1, 2013, and January 1, 2022. Kaplan-Meier analysis and log-rank tests were employed to estimate the overall survival (OS) and progression-free survival (PFS). Cox regression models were utilized to identify independent prognostic factors. Results: A total of 349 patients were included in the study, with 97.7% of patients exhibiting pure SCLC and 42.4% of patients presenting with concomitant bone metastasis. Approximately one-fourth of the patients had metastases in ≥3 organs, and 18.9% of patients had an Eastern Cooperative Oncology Group performance status (ECOG PS) ≥2. The median OS was 10.97 months (95% CI: 9.88-12.06) for those who received first-line therapy (n=286). Of these, 263 patients were treated with chemotherapy, showing a median OS of 11.37 months. Furthermore, 43.8% of patients received second-line treatment, and 81 patients proceeded to third-line treatment. ECOG PS ≥2 and mixed-SCLC were identified as independent adverse prognostic factors in SCLC with liver metastasis, whereas treatments including systemic treatment alone or in combination with local radiotherapy were associated with better prognoses. Conclusions: This retrospective study substantiated that ECOG PS ≥2 and mixed SCLC are independent predictors of poor prognosis for SCLC with liver metastasis. Additionally, different treatment strategies can improve the survival of this patient population, with chemotherapy currently being the main treatment option.