Correlation of angiogenesis and recurrence-free survival of early stage cervical cancer patients undergoing radical hysterectomy with pelvic lymph node dissection

Aim: To assess the correlation between the intensity of tumor angiogenesis, expressed as microvessel density, and recurrence-free survival in patients with early stage cervical cancer. Methods: In a historical cohort study of patients with early stage cervical cancer undergoing radical hysterectomy with pelvic lymph node dissection at Songklanagarind Hospital during January 1998-December 2004, histological slides were immunostained for factor VIII-related antigen. Microvessel density was scanned at low magnification to identify the area with the highest number of vessels. Stained microvessels were counted at high magnification (x200) in an examination area of 0.25 mm(2). Microvessel density and other potential prognostic factors were considered as covariates in multivariate Cox-proportional hazards regression models to evaluate their association with recurrence-free survival. Results: One hundred and sixty-four patients were included in the study, and 16 patients developed recurrent disease during follow-up. The overall 5-year recurrence-free survival was 86.9% (95% confidence interval [CI] 78.9-92.0). In the multivariate analysis, microvessel density (hazard ratio [HR], for >= 9 vs < 6 vessels per high power field: 5.8, 95% CI 1.5-22.7; P = 0.013), tumor size (HR for maximum diameter >= 2 vs < 2: 3.6, 95% CI 1.2-10.7; P = 0.017) and parity (HR for >= 3 vs < 3: 3.6, 95% CI 1.2-10.7; P = 0.018) were identified as significant independent prognostic factors for recurrence-free survival. Conclusion: Microvessel density is an independent prognostic parameter for recurrence-free survival in patients with early stage cervical cancer. Microvessel density at or above the cut-off point of nine vessels per high power field had significantly poorer recurrence-free survival.