Inflammation-based scores in patients with pheochromocytoma

Background Pheochromocytoma is associated with systemic inflammation but the underlying mechanisms are unclear. Therefore, we investigated the relationship between plasma metanephrine levels and hematological parameters-as a surrogate of inflammation-in patients with pheochromocytoma and the influence of preoperative alpha-blockade treatment.Design and Methods We retrospectively studied 68 patients with pheochromocytoma who underwent adrenalectomy (median age, 53 years; 64.7% females) and 2 control groups matched for age, sex, and body mass index: 68 patients with nonfunctioning adrenocortical tumors and 53 with essential hypertension. The complete blood count and several inflammation-based scores (neutrophil-to-lymphocyte ratio [NLR], platelet-to-lymphocyte ratio [PLR], lymphocyte-to-monocyte ratio [LMR], systemic-immune-inflammation index [SII], prognostic-nutrition index) were assessed in all patients and, in a subset of pheochromocytomas, after adrenalectomy (n = 26) and before and after preoperative alpha-blockade treatment (n = 29).Results A higher inflammatory state, as indicated by both complete blood count and inflammation-based scores, was observed in patients with pheochromocytoma compared with nonfunctioning adrenocortical tumors and essential hypertension. Plasma metanephrine levels showed a positive correlation with NLR (r = 0.4631), PLR (r = 0.3174), and SII (r = 0.3709) and a negative correlation with LMR (r = 0.4368) and prognostic-nutrition index (r = 0.3741), even after adjustment for age, sex, ethnicity, body mass index, and tumor size (except for PLR). After adrenalectomy, we observed a reduction in NLR (P = .001), PLR (P = .003), and SII (P = .004) and a concomitant increase in LMR (P = .0002). Similarly, alpha-blockade treatment led to a reduction in NLR (P = .007) and SII (P = .03).Conclusion Inflammation-based scores in patients with pheochromocytoma showed pro-inflammatory changes that correlated with plasma metanephrine levels and are ameliorated by adrenalectomy and alpha-blockade.