MMDA-17 TREATMENT PATTERNS AND SURVIVAL IN LEPTOMENINGEAL METASTASES
Anna Helena Preger-Guida, Heather Orosco, Victoria Wu, Kathryn Tringale, Jona Hattangadi-Gluth, David PiccioniAbstract
Background
Leptomeningeal metastasis (LM) is a severe complication of advanced metastatic cancer, with poor prognosis and limited therapeutic options. The optimal treatment strategy is unclear. This study evaluated overall survival (OS) associated with different combinations of treatment modalities in patients with LM.
Methods
We conducted a retrospective cohort study of 94 patients with LM treated at our tertiary cancer center (breast n = 57, lung n = 25, other n = 12). OS was defined as time from LM diagnosis to death. Survival was estimated using Kaplan–Meier methods. Cox proportional hazards models evaluated associations between treatment exposures and OS, adjusting for primary cancer type, age, sex, and baseline Karnofsky Performance Status (KPS). Interaction between intrathecal (IT) therapy and KPS was assessed.
Results
The median OS was 9.3 months. 79% received systemic therapy, 68% radiotherapy (13% craniospinal), and 84% IT therapy. IT therapy and systemic therapy were associated with improved survival in unadjusted analysis (p < 0.001). CSI demonstrated a trend towards improved OS (p = 0.068), whereas other RT did not. Patients receiving IT as part of combination therapy with other modalities had improved OS compared with those that did not (p = 0.012). In multivariable analysis adjusting for baseline characteristics, IT therapy remained strongly associated with improved survival (HR 0.26, 95% CI 0.13–0.51, p < 0.001). A significant interaction between IT therapy and KPS was observed (p = 0.019), with a greater relative benefit among patients with KPS < 80. Higher KPS was associated with improved survival.
Conclusions
IT therapy was strongly associated with improved survival, especially as part of combined modality regimen, with the greatest relative benefit observed among patients with poorer functional status. These findings also suggest that IT therapy may be underutilized in patients with lower KPS.