Impact of Serum Albumin Levels on FDG Uptake in the Liver, Spleen, and Bone Marrow During Gastrointestinal Cancer Staging: A PET-CT Study

Background: Serum albumin is an essential biomarker in cancer patients, reflecting nutritional status and systemic inflammation. This study investigates the impact of serum albumin levels on FDG uptake in the liver, spleen, and bone marrow during the staging of gastrointestinal cancers using FDG PET-CT. Methods: This retrospective study included 610 patients with various types of cancers. FDG PET-CT scans were used to measure FDG uptake in the liver, spleen, and bone marrow. Patients were grouped into hypoalbuminemia (< 3.5 g/dL) and normal albumin levels (≥ 3.5 g/dL). The study analyzed the correlation between serum albumin and SuVMax and SuVMean of the liver, spleen, and bone marrow. Results: Patients with normal albumin levels exhibited significantly higher liver FDG uptake, with a mean Liver SuVMax of 3.73 ± 1.78 compared to 3.32 ± 0.75 in those with hypoalbuminemia (p < 0.0001). Similarly, Liver SuVMean was higher in the normal albumin group (2.17 ± 1.20) than in the hypoalbuminemia group (1.95 ± 0.48, p = 0.0009). No significant differences in FDG uptake were observed in the spleen and bone marrow between the two groups. The study found a weak positive correlation between albumin levels and liver FDG uptake, but no significant correlation with FDG uptake in the spleen and bone marrow. Conclusion: Serum albumin levels are significantly associated with liver FDG uptake in patients with gastrointestinal cancers, suggesting that albumin may play a role in liver metabolism. However, albumin levels do not significantly impact FDG uptake in the spleen or bone marrow. These findings highlight the potential of albumin as a marker for liver metabolism in cancer patients but suggest that other factors influence the spleen and bone marrow.