Bioelectrical impedance analysis as a quantitative measure of sarcopenia in head and neck cancer patients treated with radiotherapy

Radiother Oncol. 2021 Jun;159:21-27. doi: 10.1016/j.radonc.2021.03.005. Epub 2021 Mar 15.


Background and purpose: Sarcopenia is associated with decreased survival in head and neck cancer patients treated with radiotherapy. This study sought to determine whether in-clinic multifrequency bioelectrical impedance analysis (BIA) can identify survival-associated sarcopenia in patients with head and neck cancer.

Materials and methods: This prospective observational study enrolled 50 patients with head and neck cancer undergoing radiation therapy. Baseline BIA measures of skeletal muscle (SM) mass, fat-free mass (FFM), and fat mass (FM) were compared to CT-based estimates using linear regression. Sex-specific BIA-derived thresholds for sarcopenia were defined by the maximum Youden Index on receiver operator characteristic (ROC) curves. Patients were stratified by sarcopenia status and OS was compared using the Kaplan-Meier method and log-rank test.

Results: Among 48 evaluable patients, BIA measures of body composition were strongly correlated with CT measures: SM mass (r = 0.97; R2 = 0.94; p < 0.0001), FFM (r = 0.97; R2 = 0.94; p < 0.0001) and FM (r = 0.95; R2 = 0.90; p < 0.0001). SM mass index < 9.19 kg/m2 identified sarcopenia men with high sensitivity (91.7%) and specificity (92.9%), whereas in women SM mass index < 6.53 kg/m2 was sensitive for sarcopenia (100%), but not specific. Patients with sarcopenia, defined by either CT or BIA, exhibited decreased OS (HR = not estimable; CT p = 0.009; BIA p = 0.03).

Conclusion: BIA provides accurate estimates of body composition in head and neck cancer patients. Implementation of BIA in clinical practice may identify patients with sarcopenia at risk for poor survival.

Keywords: Bioelectrical impedance analysis; Cachexia; Head and neck cancer; Radiotherapy; Sarcopenia.

Publication types

  • Observational Study
  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Body Composition
  • Body Mass Index
  • Electric Impedance
  • Female
  • Head and Neck Neoplasms* / complications
  • Head and Neck Neoplasms* / metabolism
  • Head and Neck Neoplasms* / radiotherapy
  • Humans
  • Male
  • Muscle, Skeletal
  • Sarcopenia* / diagnosis
  • Sarcopenia* / etiology