JOURNAL OF CLINICAL MEDICINE, cilt.2025, sa.14, ss.1-12, 2025 (SCI-Expanded, Scopus)
Abstract Background/Objectives: In patients with malignancy, fluid electrolyte imbalance and renal dysfunction have been demonstrated to increase mortality and morbidity. The objective of this study was to evaluate body composition, and clinical and laboratory tests at baseline and at 3 months during chemotherapy and standard fluid therapy in patients with malignancy. Methods: This study included patients with an ECOG performance status of 0–1 who did not have clinically evident organ failure, brain tumors, or a need for intensive care treatment. All received standard fluid therapy and chemotherapy. Examinations, routine laboratory tests, and body composition measurements were performed at the beginning of chemotherapy and again after three months. Results: The number of hypervolemic patients increased. Although the body mass index (BMI) did not change compared to the baseline, serum levels of B-type natriuretic peptide (BNP), calcium, albumin, total cholesterol, high-density lipoprotein (HDL) cholesterol, and triglycerides increased at the second measurement. By month three, the frequency of overhydration (OH) increased. There was a significant, positive, moderate correlation between the difference in OH and the difference in BNP (p = 0.001). The leukocyte, neutrophil, neutrophil-to-lymphocyte ratio, and neutrophil-to-albumin ratio decreased (p < 0.05 for all). Body composition monitor (BCM) measurements revealed that the extracellular fluid/intracellular fluid ratio (E/I) increased at the second measurement (p = 0.001). Conclusions: The frequency of OH and BNP levels increased at three months. An initial fluid deficit or OH was associated with mortality. OH may mask sarcopenia in patients. Therefore, objective assessment of body composition is important for patient management to avoid OH and predict mortality. However, more studies with larger patient populations and long-term follow-up are needed. Keywords: body composition monitor; overvolemia; antineoplastic chemotherapeutic agent; overhydration