Risk assessment of intra-operative hemodynamic instability in patients with pheochromocytoma

Pheochromocytoma (PHEO), a neuroendocrine tumour characterized by catecholamine hypersecretion, poses significant peri-operative challenges due to unpredictable intra-operative hemodynamic instability (IHI). This investigation sought to characterize clinicopathological predictors of IHI and develop a risk-stratification tool to optimize surgical management.

In this retrospective cohort study, 98 patients with histologically confirmed PHEO underwent comprehensive predictor screening via univariate and least absolute shrinkage and selection operator (LASSO) regression analyses. Cohort stratification allocated 70% (69 patients) to model development and 30% (29 patients) for validation. Predictive performance was rigorously assessed through receiver operating characteristic (ROC) analysis, bootstrap-corrected calibration curves (1,000 iterations), and decision curve methodology.

Multivariable modelling identified three independent predictors of IHI: plasma normetanephrine (NMN) level (OR 1.84 [95% CI 1.04 to 3.33]), total bilirubin (TBIL; 9.75 [SD 5.36] versus 7.50 [SD 2.96] µmol/L, P < 0.05), and maximum diameter (MaxD; 5.17 [SD 2.14] versus 4.25 [SD 1.53] cm, P < 0.05). The composite nomogram demonstrated robust discriminative capacity, achieving area under curve of 0.76 (0.90 sensitivity) and 0.80 (0.73 sensitivity) in training and validation cohorts, respectively. Bootstrap validation revealed excellent calibration accuracy, while decision curve analysis confirmed superior net benefit versus NMN level-only predictions across clinical probability thresholds.

By integrating biochemical, anatomical, and functional parameters, this triparametric risk-stratification model enables pre-operative identification of high-risk PHEO patients, developing personalized peri-operative management strategies to mitigate catecholamine-driven complications.