MON-800 Evaluation of Bone Mineral Density in Patients With Gastrointestinal Tumors Before and After Treatment With Chemotherapy and High Doses of Dexamethasone: A Case Series

Abstract

Disclosure: M. Aguilar-Soto: None. D. Cuenca: None. F. Huitzil-Melendez: None. M. Meneses-Medina: None. A. Reza-Albarrán: None.

Glucocorticoids are associated with a wide range of adverse effects with over 50% of chronic users developing osteoporosis. The risk of osteoporosis is known to correlate with the duration of exposure and high dosages, with changes in bone microarchitecture detectable as early as three months of use. Nausea prevention prior chemotherapy administration is crucial to avoid complications such as vomiting and dehydration and treatment abandonement due to side effects. High doses of dexamethasone are commonly recommended for nausea prevention in many chemotherapy regimens, especially those with high or moderate emetic risk. However, the impact of dexamethasone on bone health during chemotherapy has not been extensively studied. We conducted a unicentric, prospective, observational study measuring bone mineral density using dual-energy X-ray absorptiometry, alongside assessments of N-terminal procollagen type 1 peptides, bone alkaline phosphatase, a bone profile, and muscle mass in patients with gastrointestinal tumors eligible for chemotherapy with dexamethasone premedication. Measurements were taken prior to treatment and six months afterward.Twenty-two patients were recruited; with six excluded due to baseline osteoporosis and one due to treatment discontunuation. Six patients were lost to follow-up, and three died, leaving five patients who completed follow-up and one currently under observation. Mean age was of 48.8 years (SD 13.3), with 80% male participation. Diagnoses included were colon adenocarcinoma (20%), gastric adenocarcinoma (40%) and colangiocarcinoma (40%). All were diagnosed in stage IV; three had diabetes. The mean acumulated dose of dexametasone was of 83.2 mg (SD 19.3). No significant changes were observed in general laboratory values. Bone mineral density assessments revealed a decrease of 4.3% in femoral neck and total hip, and a decrease of -3.6% was observed for lumbar spìne. For the T-scores, decreases of -154% in femoral neck, -119% in total hip and -53% in lumbar spine were noted. None of the patients reach T-scores that were diagnostic of osteoporosis.While no significant changes occurred in urinary hydroxyproline or PTH, N-telopeptide levels increased by 252% at six months. Our study suggests that the use of high doses of dexamethasone for nausea prevention may negatively impact bone health.

Presentation: Monday, July 14, 2025