Capacitance of Membrane As a Prognostic Indicator of Survival in Head and Neck Cancer.

Abstract

BACKGROUND: Evaluation of prognostic value of capacitance of membrane (Cm), parameter measured by bioelectrical impedance (BIA) as an alternative to known clinical factors in patients with Head and Neck Cancer (HNC). METHODS: A cohort of 75 stage IIIB and IV HNC patients treated in Department of Otolaryngology, Head and Neck Surgery, Medical University of Lublin, Poland were prospectively evaluated. Cm measurements were performed in all patients using a bioelectrical impedance analyzer that was set on a frequency of 50 kHz. Results of Cm measurements were presented in nF. Survival differences were estimated using Kaplan-Meier method. RESULTS: Significantly higher Cm median was noted in well-nourished(n = 45) compared to malnourished (n = 30) patients (1.41 vs 1.01 respectively; p = 0.0009). Established in ROC curves analysis cut-off value (0.743) was characterized by 98% specificity and 37% sensitivity in the detection of malnutrition. Median overall survival (mOS) in the cohort was 32months. At the time of analysis deaths were recorded in 47 cases (62.7%). In patients who had Cm below the level of 0.743 risk of OS shortening was significantly higher than in other patients (12.1 and 43.4 months respectively; HR = 8.47, 95%CI: 2.91-24.66; χ2 = 15.38, p = 0.0001). CONCLUSION: Cm is a strong, independent prognostic factor in head and neck cancer.