Bioelectrical impedance phase angle as a prognostic indicator of survival in head-and-neck cancer.
BACKGROUND
Phase angle could be an alternative to subjective global assessment for the assessment of nutrition status in patients with head-and-neck cancer.


METHODS
We prospectively evaluated a cohort of 75 stage iiib and iv head-and-neck patients treated at the Otolaryngology Department, Head and Neck Surgery, Medical University of Lublin, Poland. Bioelectrical impedance analysis was performed in all patients using an analyzer that operated at 50 kHz. The phase angle was calculated as reactance divided by resistance (Xc/R) and expressed in degrees. The Kaplan-Meier method was used to calculate survival.


RESULTS
Median overall survival in the cohort was 32.0 months. At the time of analysis, 47 deaths had been recorded in the cohort (62.7%). The risk of shortened overall survival was significantly higher in patients whose phase angle was less than 4.733 degrees than in the remaining patients (19.6 months vs. 45 months,p= 0.0489; chi-square: 3.88; hazard ratio: 1.8856; 95% confidence interval: 1.0031 to 3.5446).


CONCLUSIONS
Phase angle might be prognostic of survival in patients with advanced head-and-neck cancer. Further investigation in a larger population is required to confirm our results.
HTA Consulting, Cracow, Medical University of Lublin, Lublin, Poland.
M S
MS
Władysiuk
Human Physiology Department, Medical University of Lublin, Lublin, Poland.
R
R
Mlak
Epidemiology Department, Medical University of Lublin, Poland.
K
K
Morshed
Electronics Department, Lublin University of Technology, Lublin, Poland.
W
W
Surtel
Oncology Department, Medical University of Lublin, Lublin, Poland.
A
A
Brzozowska
Human Physiology Department, Medical University of Lublin, Lublin, Poland.
T
T
Małecka-Massalska
Head-and-neck cancer; bioelectrical impedance analysis; phase angle; prognostic factors; survival