(ChemotherapyAdvisor) – High serum levels of endostatin are associated with poor survival rates among patients with advanced nasopharyngeal carcinoma (NPC), according to a prospective cohort study recently published in Clinical Oncology.
This finding might allow improved risk stratification of NPC patients, noted senior author Hai-Qiang Mai, MD, PhD, of the State Key Laboratory of Oncology in South China, in Guangzhou, China, and coauthors.
The authors measured pretreatment serum endostatin and vascular endothelial growth factor (VEGF) levels in 218 patients diagnosed with advanced NPC between 2003 and 2005, and 20 healthy control participants, using competitive enzyme immunoassays. The 5-year overall survival (OS), progression-free survival (PFS), and distant metastasis-free survival (DMFS) rates were then compared between patients with high and low levels of endostatin
Serum endostatin levels were significantly higher in patients with NPC than healthy controls (P=0.0001) but VEGF levels were similar between the two groups (P=0.42), the authors noted. No associations were identified between pretreatment VEGF levels and NPC survival rates, but endostatin levels were significantly associated with all three survival measures, they found.
Among an initial group of 70 patients with NPC, 5-year OS was 63.9% for the group of high-endostatin patients and 90.5% among low-endostatin patients (P=0.003), and PFS was 50.2% versus 79.3% (P=0.003), the authors reported. Elevated endostatin was also prognostic of poor DMFS (59.1% vs. 85.3%; P=0.01). The 148 patients with NPC in a subsequent validation cohort yielded similarly superior survival rates for low-endostatin patients (OS and PFS, P=0.001; DMFS, P=0.002), the authors reported.
When all patients’ data were included in a single multivariate analysis, serum endostatin level prior to treatment remained a significant, independent unfavorable prognostic factor for OS (HR 4.8; 95% CI: 2.48-9.23; P<0.0001), PFS (HR 3.44; 95% CI: 2.06-5.74; P<0.0001) and DMFS (HR 3.65; 95% CI: 1.92-6.94; P<0.0001), they reported.
Validation of the findings is needed, the authors cautioned. But the study “provides the first evidence that serum endostatin levels may serve as a useful prognosticator for advanced-stage NPC,” they wrote.