Dynamic changes in liver-to-spleen ratio: can it be a prognostic biomarker for chemo-immunotherapy in small cell lung
Yi Ren1,2,3, Weiwei Liu1,2,3, Jie Lou1,2,3
1Department of Radiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
Background:
The liver-to-spleen ratio (LSR) is a non-invasive imaging biomarker used to assess non-alcoholic fatty liver disease (NAFLD). Given the potential link between the NAFLD-associated immune microenvironment and systemic anti-tumor immunity, we hypothesized that NAFLD-as defined by LSR-might predict clinical outcomes in small cell lung cancer (SCLC) patients treated with chemo-immunotherapy. This study aimed to evaluate the association between LSR-defined NAFLD, dynamic LSR changes, and treatment efficacy in SCLC patients receiving chemotherapy or chemo-immunotherapy.
Methods:
The study comprised 314 SCLC patients treated at Wuhan Union Hospital between March 2015 and March 2024; 160 received chemo-immunotherapy and 154 received chemotherapy alone. NAFLD was defined as LSR ≤1.1 on baseline computed tomography (CT) scans. Dynamic LSR changes were assessed using two follow-up measurements taken 1-3 months apart. Primary and secondary endpoints were overall survival (OS) and progression-free survival (PFS), objective response rate (ORR), and disease control rate (DCR), respectively. Survival analyses were performed using Kaplan-Meier curves and Cox regression models.
Results:
The prevalence of LSR-defined NAFLD at baseline was comparable between the chemo-immunotherapy group (36 cases, 22.5%) and the chemotherapy group (41 cases, 26.6%). No significant differences in OS or PFS were observed between NAFLD and non-NAFLD subgroups in either treatment cohort (all P>0.05). Although the second LSR measurement in the chemotherapy group indicated worse OS in the non-decreased group (9.7 vs. 13.3 months, P=0.03), dynamic LSR changes at all other time points-including those from the chemo-immunotherapy group-did not demonstrate significant prognostic value (all P>0.05). Multivariate analysis confirmed that neither LSR-defined NAFLD status nor dynamic LSR changes were independently associated with survival outcomes.
Conclusions:
Neither baseline LSR-defined NAFLD status nor short-term dynamic LSR changes predicted treatment outcomes in SCLC patients undergoing chemotherapy or chemo-immunotherapy. These results suggest that NAFLD may not contribute meaningfully to immunotherapy resistance mechanisms in SCLC.
