OC32 - Inflammation-based scores in patients with pheochromocytoma: a study of 69 cases

Abstract Introduction Pheochromocytoma is related with systemic inflammation, though the underlying mechanisms remain unclear. In this study, we aimed to investigate the relationship among plasma levels of methoxy derivatives and hematological inflammatory parameters in these patients. Materials and Methods We performed a retrospective, descriptive, and analytical study on patients with histologically confirmed pheochromocytoma operated at the Endocrinology, Diabetology, and Nutrition Department of Hassan II University Hospital of Fez, between January 2009 and January 2024. Patients were divided into three groups:N1: Patients with pheochromocytomaN2: Control group of patients with essential hypertension without adrenal tumorsN3: Control group of patients with non-functioning adrenal tumors All patients underwent evaluation of inflammation-based scores, including:Neutrophil-to-Lymphocyte Ratio (NLR)Platelet-to-Lymphocyte Ratio (PLR)Lymphocyte-to-Monocyte Ratio (LMR)Systemic Inflammation Index (SII) Patients with insufficient records were excluded. Statistical analysis was performed using SPSS version 26. Results A total of 207 patients were included:69 patients with pheochromocytoma, with a mean age of 49 years and a female predominance (76.2%).69 patients with essential hypertension (N2) matched for age, sex, and BMI.69 patients with non-functioning adrenal tumors (N3), also matched for age, sex, and BMI. In a subgroup of pheochromocytoma patients (N1a), inflammatory markers were assessed both before and after preoperative alpha-blocker therapy. Multivariate analysis showed:A positive correlation between elevated plasma methoxy derivatives and NLR (p = 0.021), PLR (p = 0.02), and SII (p = 0.04).A negative correlation between elevated methoxy derivatives and LMR (p = 0.052).A positive association between alpha-blocker treatment and improvement in LMR and SII scores.Inflammation-based scores were significantly higher in pheochromocytoma patients compared to both control groups (p = 0.024), with no significant difference between the two control groups (p = 0.006). Conclusion Inflammation-based scores indicate a pro-inflammatory state in pheochromocytoma, which correlates with plasma methoxy derivative levels. These inflammatory markers improve following alpha-blocker therapy as well as adrenalectomy, suggesting prospective value in guiding therapeutic strategies.