Association between time from cancer diagnosis to surgery for femoral metastasis and overall survival among patients with malignancy.

BACKGROUND: The prognostic significance of the interval between initial cancer diagnosis and development of femoral metastasis requiring surgery remains unclear. This study evaluated the association between this interval and overall survival in patients undergoing surgery for metastatic femoral lesions. METHODS: A retrospective cohort study was conducted among 314 patients treated surgically for metastatic femoral disease at a single center between 2005 and 2019. The primary exposure was the interval between cancer diagnosis and surgery for femoral metastasis: <1 year, 1-5 years, and >5 years. Data included demographics, tumor type, fracture status (actual versus impending), surgical modality, and Karnofsky performance score. Survival was assessed using Kaplan-Meier analysis, log-rank testing, and multivariable Cox regression adjusting for clinical and demographic variables. RESULTS: Median overall survival was 10 months (IQR 3-28). Survival differed significantly among diagnostic-interval groups (p < 0.001), with median survivals of 14 months in the <1-year group, 7 months in the 1-5-year group, and 14 months in the >5-year group. In multivariable analysis, a 1-5-year interval was associated with higher mortality compared with <1 year (HR = 1.79, 95% CI 1.31-2.43). Lower Karnofsky performance status and actual versus impending fracture were also independently associated with increased mortality. CONCLUSIONS: The interval between cancer diagnosis and surgery for femoral metastasis is independently associated with overall survival. Incorporating this readily available clinical variable may serve as a complementary factor in preoperative survival assessment and assist in patient counseling and surgical planning.