Purpose:
This study aimed to investigate whether the
extracellular-to-intracellular fluid volume (E/I) ratio can predict survival in
patients with metastatic cancer.
Methods:
Clinical data were
collected from April 2016 to March 2018. Patients aged ≥19 years with metastatic
solid tumor were eligible. Bioimpedance analysis was used to assess body fluid
distribution and the E/I ratio. Clinical characteristics, including laboratory
test results and nutrition status according to the E/I ratio, were analyzed. Cox
proportional hazards models and Kaplan-Meier analysis were used to identify risk
factors for mortality.
Results:
In total, 87 patients were included
in the study. The 87 patients were divided into 2 groups according to the median
E/I ratio: a high E/I group (E/I ratio ≥1.0, n = 43) and a low E/I group (E/I
ratio <1.0, n = 44). Poor performance status, fluid retention, malnutrition,
elevation of C-reactive protein levels, and decreases in hemoglobin, albumin,
and protein levels were significantly associated with the high E/I group. The
median overall survival time was 1.6 and 12.5 months in the high E/I and low E/I
groups, respectively (
P
< .001). In the multivariate
analysis, poor performance status, leukocytosis, fluid retention, and E/I ratio
were independent prognostic factors, and the E/I ratio was the strongest
prognostic factor predicting overall survival (hazard ratio = 3.49, 95%
confidence interval = 1.75-6.96,
P
< .001).
Conclusions:
The E/I ratio can predict survival time in
patients with metastatic cancer. More rigorous research is required to confirm
this result.