The significance of perineural invasion in early-stage cervical cancer

Introduction Cervical cancer spreads directly and through lymphatic and vascular channels. Perineural invasion is an alternative method of spread. Several risk factors portend poor prognosis and inform management decisions regarding adjuvant therapy. Objective To evaluate the incidence and significance of PNI in early cervical cancer. Methods Retrospective chart review of early-stage cervical cancer patients (IA-IIA) from 1994 to 2009. Results One hundred ninety two patients were included, 24 with perineural invasion in the cervical stroma (cases) and 168 without (controls). The mean age of the cases was 53 years, versus 45.9 in the controls (P = 0.01). PNI was associated with more adjuvant therapy (P = 0.0001), a higher stage (P = 0.005), a larger tumor size (≥ 4 cm) (P < 0.0001), lymphovascular space invasion (P = 0.002), parametrial invasion (P < 0.0001) and more tumor extension to the uterus (P = 0.015). On multivariate analysis using an adjusted hazard ratio, risk factors for recurrence included grade (HR, 95% CI; 3.61, 1.38-9.41) and histopathology (HR, 95% CI; 2.85, 100-8.09). Similarly, risk factors for death included grade (HR, 95% CI; 3.43, 1.24-9.49) and histopathology (HR, 95% CI; 3.71, 1.03-13.33). Perineural invasion was not identified as an independent risk factor for either recurrence or death. The mean follow up time was 56 months. There was no significant difference in recurrence (P = 0.601) or over-all survival (P = 0.529) between cases and controls. Conclusion While perineural invasion was found to be associated with multiple high-risk factors, it was not found to be associated with a worse prognosis in early cervical cancer.